Hot Water Demand Systems & Tankless Water Heaters – Great Home Improvement Products!

If you are looking for home improvement products, here is a great combination. Tankless hot water is energy efficient but it wastes water. Adding a hot water demand system will make your tankless unit water efficient as well. It will make turn your plumbing system into a green hot water system.

Tankless water heaters are more energy efficient than standard tank type water heaters because they don’t have the standby losses of a big tank of hot water. By eliminating the standby losses associated with storage water heaters they can save about 20 percent of the energy consumed for heating water when compared with storage heaters.

However, the tankless units also take longer to deliver hot water to your fixtures. For the water to be heated to full temperature it must pass completely through the heat exchanger all the way from the inlet to the outlet. The water in the center of the heat exchanger doesn’t ever reach full temperature before it exits the heater.

Thus tankless waters take longer to get hot water to the fixture. A lot more water is being run down the drain while you are waiting. Tankless water heaters really need a hot water demand system to address this problem.

Hot water demand systems typically consist of a pump located at the furthest sink from the water heater and connected to the hot and cold water lines. When hot water is “demanded” at the fixture you activate the system. The demand system speeds the water from the water heater to the fixture at high velocity and shuts off when the hot water reaches the pump.

The cold hot water in the hot water pipes left over from the last use gets sent to the water heater inlet through the cold water pipes. Instant hot water when you turn on the hot water faucet, and no water was wastefully run down the drain.

Traditional hot water recirculation systems with their low powered pumps won’t produce enough water flow in the pipes to turn on a tankless heater. Most tankless water heaters won’t work with traditional circulating systems and can void the warranty of the tankless heaters.

Hot water demand systems are different. Since demand systems are activated only when hot water is used they do not cause the tankless heater to cycle on and off over and over as is the case with traditional recirculation pumps. Demand systems do not affect the warranties for the tankless units.

Not all demand systems are created equal and there are models that don’t have enough power to turn on a tankless water heater. Be sure to find a pump that has the power to you need to send at least the ½ to ¾ gallons per minute normally required to turn on the heater. Longer pipe runs require more horsepower from the pump to produce the required flow, so take that into account as well.

Add a hot water demand system to your water heater and you will conserve energy, water, and money. At the same time you are turning your plumbing system green, and you will be reducing your carbon footprint. You will feel good every time you use hot water.

Finally, water conservation without inconvenience!

Combine Tankless and Demand

Takagi - Noritz - Rinnai - Navien – Comparison of Tankless Water Heaters

Of the major brands of tankless hot water heaters Noritz, Navien, Takagi, & Rinnai, which brand is best? I recently asked a friend of mine this question. He installs and services tankless water heaters so I figured if anyone would know he would. Here is his reply.

All the major brands of tankless hot water heaters are very similar in construction, operation, and quality. Each brand has claims by the manufacturer that theirs is better, but nothing really stands out in my opinion, to differentiate between the brands.

Noritz advertises its "Dual Burner" technology as a big advantage. Is that a significant advantage over the others? I don’t think so. Since all of the brands modulate the flames I don’t think having two small burners is any better than one larger burner. In fact, if I had to choose I would take the single burner since it is simpler and I think simpler is better.

Rinnai, Noritz, and Takagi are all made in Japan and Noritz and Takagi both share some components, and they have similar warranties. Rinnai uses a different venting system than Noritz and Takagi. Do I think its better? Not really.

I do like the fact that Rinnai tankless water heaters have a built-in condensation trap. Sometimes installers forget or just don't bother to include the condensation trap when installing a tankless water heater because of the additional cost. This can result in a much shorter life expectancy for the heat exchanger. Unless the customer knows something about tankless heater installations he would have no idea that it was missing. Vent condensation is highly corrosive and should not be allowed to drip on parts of your water heater.

Navien tankless water heaters are made in South Korea. Navien is better established in Canada. The Navien units have unique and interesting features, like a built in small buffer tank that lets you obtain low flows of hot water and eliminates cold water sandwiches.

Navien heaters have 98% efficiency while the other major brands have about 94%. Is the 4% difference significant? It would not be enough for you to notice on your utility bill.
Navien, Noritz, Rinnai and Takagi are mechanically very similar. They all deliver roughly the same amount of hot water for the gas or electricity used. The warranties are all pretty much the same.

I personally like Takagi because of their excellent service. They even have a toll free number 24/7 that I can call when there is a problem. When your hot water heater stops working on Friday night, and you can’t get any help until Monday morning you can become quite frustrated.

I feel that the most important thing when buying a tankless water heater is to be sure that heater is installed correctly; it is not like your standard storage type water heater where you connect a couple of pipes up and you are done.

With a tankless hot water heater It is very important to purchase it and have it installed by a plumber that is experienced with tankless water heaters particularly with the brand you are purchasing. If you experience problems in the future, you will be glad you did.

Another tankless water heater comparison article: Compare Bosch, Takagi, Noritz & Rinnai

The Takagi T-K-Jr Tankless Hot Water Heater – A Product Review

Let’s take a brief look at the T-K Jr. the smallest water heater in the Takagi line of tankless water heaters.

According to Takagi, it can meet the hot-water needs of a small home or apartment with one or two bathrooms, as well as small commercial applications.

Takagi claims it was designed to do anything a standard 40-gallon tank-type water heater can do. The T-K Jr. works with both hydronic baseboard and radiant floor heating. It has an energy efficiency rating of .81 when burning natural gas and can provide 3.8 gallons per minute with a 60 degree temperature rise. The maximum input is 140,000 Btu.

When the water heater detects a flow of at least 0.75 gallons per minute, the heater turns on. While The computer in the controls monitors the water temperature, flow rate and gas flow.

When the burners ignite, a lamp comes on telling you the tankless water heater operating normally. The internal computer controls the gas valve and controls the water flow to maintain the preset water temperature of the water at the outlet
While reading through the owner’s manual, which you can find online at Takagi’s site, I ran found the following statement:

“The unit should be checked once a year or as necessary by a licensed technician. If repairs are needed, any repairs should be done by a licensed technician. The following systems and parts should be checked at least once a year:
1. Venting system
2. Burner
3. Manual operation of the pressure relief valve to ensure correct operation.
4. Periodic cleaning of the water filter (figure above).
5. Heat exchanger. Remove the thermistor and check for a mineral coating. A mineral
coating on the thermistor requires flushing the heat exchanger with a de-scaling
solution. Scale build up will void your warranty and shorten the life of your water
heater.”

You might have to add the cost of a yearly maintenance check to the costs of your tankless water heater, and that could reduce the savings from your tankless water heater.

Elsewhere in the Takagi site I read this:

“8. Water hardness may affect the water heater. Water heater may be damaged. The warranty will not cover damage caused by water quality.”

It’s something for you to think about if you live in a hard water area.

The Takagi T-K Jr requires a 110 Volts to operate the controls, so if there is a power failure your tankless water heater won’t be able to provide you with hot water.
The T-KJR can be used for space heating, and potable hot water heating at the same time.

The owner’s manual includes information on how to use the hot water heater for baseboard and for radiant heating applications and comes complete with diagrams of typical systems.

Turn your hot water plumbing green with an energy efficient Takagi tankless hot water heater.

Going Green? – Water Conservation Products

What is green plumbing? Well, green plumbing when applied to residential plumbing layouts, would mean plumbing that reduces your energy and or water wastage; an efficient plumbing system.

There are a variety of products out there that can save you water, but some are counter productive and some are a pain in the you-know-what. Others are certainly worthwhile and can even save you money.

The biggest factor involved in water and energy wastage is human behavior. It’s our behaviors that waste the most energy and the most water. We all do it… leave lights on, leave water running when not necessary, linger in the shower… Going green seems to often lead to less convenience. But humans are after exactly that… convenience. That’s why microwave ovens, took off. Dishwashers, washing machines, trash compactors, automatic sprinkler systems, it’s all about convenience.

Some water conservation products address these behaviors. Low flow fixtures reduce the rate at which water flows from a fixture, so we use less water when we leave it running. This can be an inconvenience though, when you have to stand there and wait longer to fill up that pitcher or sink. Low flow toilets that don’t always work with one flush.

There are numerous “gray water” systems that reclaim waste water like from your washing machine to use in flushing toilets or watering the lawn.

It’s not hard to find water saving appliances such as dishwashers and washing machines. Probably all of them now at least have water conservation cycles or modes. I recently was talking to a guy who had just bought a new Bosch water conserving dishwasher. He was having a problem because the dishwasher didn’t draw a high enough flow of water to turn on the water heater. To get clean dishes he has to run hot water in the sink while the dishwasher fills. So much for water conservation.

There are some water conservation products which do offer both convenience and save water. The Chilipepper hot water demand system is one such water conservation product. It gets you your hot water faster and you don’t run any water down the drain. The pump is very efficient consuming less than $2.00 per year in electricity to operate. Not only are you saving water and energy with the Chilipepper, but you are also reducing your carbon foot print.

Every gallon of water that you do not dump down the drain is one gallon less sewage that has to be treated and pumped etc which in turn uses less energy and thus results in reduced green house gas being released into the atmosphere.

Don’t confuse the Chilipepper hot water demand systems with one of those “luke warm circulating systems” on the market like the Laing Autocirc, the Grundfos Comfort System, and the Watts Premier.
These systems circulate warm water through the hot water piping and the cold water piping, but in doing so consume a lot of energy making your water heater work harder and costing you money. You also end up with less than cold water in your cold water lines and you must purge those lines of the lukewarm water to get cold water from the faucet.

Tankless water heaters typically take longer to get hot water to your fixtures wasting more water than hot water systems that use tank type water heaters. The good news is the Chilipepper works with any brand of tankless water heaters including Rinnai water heaters, Takagi water heaters, Bosch water heaters, Rheem water heaters, Noritz water heaters, and all other brands too.

So go green and install a hot water demand system. It’s a very earth friendly thing to do. You will feel good about what you are doing for the planet and you get the added convenience of fast hot water!

A Water Heater and a Demand Pump - Instant Hot Water for Less Than $200

If you want instant hot water from your water heater when you turn on the faucet, then you want a demand pump. A hot water demand pump system is not the same as a recirculating or recirculation pumping system.

Recirc Pumps

Recirculation pumps, often referred to as “recirc pumps”, are for circulating a small flow of water through the piping system continuously to provide you with instant hot water when you turn on the spigot. Although you get instant hot water when you turn on the faucet, the system wastes a tremendous amount of energy since the hot water piping acts like a giant radiator. The water heater has to work much harder to replace all the lost heat and that costs you money. It also produces more green house gasses.

Demand Pumps

Demand pumps only pump hot water through the piping to your fixture when you “demand” it by pressing the pump’s start button. You won’t use any more energy than normal since you are only filling the pipe with hot water, just like you would if you turned on the tap and ran the water down the drain while you waited.

The pump typically runs for less than a minute, and thus uses very little energy of its own. The pump usually uses less than $2.00 per year in electricity.

Tankless Water Heaters

Although normal recirc pumps and recirculation systems will not work with tankless water heaters, demand pumps will, if they have enough power to turn on the heater. The Chilipepper pump has enough power to turn on any tankless water heater on the market. Others such as the Metlund D’mand System pumps have several models with different amounts of power, and some models will turn on some heaters. Be sure to check before you buy!

Tankless hot water heaters require more time to get the hot water to your fixtures since they have to heat the water first. Typically 10 to 20 seconds longer. That means you run more water down the drain waiting. With tankless hot water demand pumps are even more beneficial than with storage type water heaters.

A Green Plumbing Product

By installing a hot water demand system you not only get the convenience of fast hot water, you reduce your carbon footprint. It takes energy to pump and treat both the potable water in your residential plumbing, and the resulting sewage water from running it down the drain. By using less energy for pumping and treating the water, you release less pollution and green house gas into the atmosphere.
The Chilipepper hot water demand pump costs well under $200.00, and will pay for itself, often in a year or so.

State Industries Storage and Tankless Gas and Electric Hot Water Heater Website.

A Quick Look At State Storage and Tankless Gas and Electric Water Heaters

OK, that’s it. I’ve looked at the State water heater site, and it is just the same as all the rest. Besides the ones I’ve recently blogged about, I’ve also written articles about Rinnai, Takagi, Noritz, and Bosch tankless water heaters. You can see the articles here: Bosch Noritz Takagi Rinnai

While reading through the manual for one of the tankless water heaters I ran across this tid-bit, and I’ve seen it with other brands of tankless hot water heaters too.

An “LC” or “00” error code indicates the unit is beginning to lime up and must be flushed. Failure to flush the appliance will cause damage to the heat exchanger. Damage caused by lime build-up is not covered by the unit’s warranty. After flushing, reset the LC fault code by turning off the power to the unit and turning the power back on.

Here is what you need and instructions on how to flush the lime out of the tankless water heater…

Circulating Pump
5 gallon pail of virgin, food grade, white vinegar (or virgin, food grade, citric acid).
Cold Water Line
Hot Water Line
In-line Filter

1. Disconnect electrical power to the water heater.
2. Close the shutoff valves on both the hot water and cold water lines (V3 and V4).
3. Connect pump outlet hose (H1) to the cold water line at service valve V2.
4. Connect drain hose (H3) to service valve V1.
5. Pour approximately 4 gallons of virgin, food grade, white vinegar or citric acid into pail.
6. Place the drain hose (H3) and the hose (H2) to the pump inlet into the cleaning solution.
7. Open both service valves (V1 and V2) on the hot water and cold water lines.
8. Operate the pump and allow the cleaning solution to circulate through the water heater for at least 45 minutes.
9. Turn off the pump.
10. Rinse the cleaning solution from the heater as follows:
a. Remove the free end of the drain hose (H3) from the pail.
b. Close service valve, (V2), and open shutoff valve, (V4).
Do not open shutoff valve, (V3).
c. Allow water to flow through the heater for 5 minutes
d. Close service valve, (V1), and open shutoff valve, (V3).
11. Disconnect all hoses.
12. Remove the in-line filter at the cold water inlet and clean out any residue. Place filter back into unit.
13. Restore electrical power to the water heater

Boy doesn’t that sound like fun? Something to consider when you are trying to choose between a storage water heater and a tankless unit.

State water heaters has some electric water heaters that have 3 inch thick insulation and have an energy factor of .94. I think that is the highest I have ever seen for an electric storage type water heater.

Not much else of interest at the State site, so that’s it for now.

I think I will try to find a new topic for my next blog. I am all water heater’d out.

Bill the Hot Water Guy

General Electric Water Heaters, Storage, Heatpump, and Tankless Water Heaters

G.E. Water Heaters and Web Site

One would think that GE, as big and wealthy as it is, could do better than number 15 in the Google search results, but that is where it is.

The first thing you see when you arrive on the home page is GE’s new “Hybrid” water heater… a heat pump water heater. It’s not on the market yet, but is supposed to be available later this year, I think it said November.

The heat pump is mounted on what I presume to be a standard electric water heater and the controls allow you to run it in several modes, like heat pump only, heat pump with electric assist, and electric only etc. There is a vacation mode too.

GE’s heat pump water heater has an impressive Energy Factor of 2.3! That is the best I have ever seen. So if you really want a green plumbing system, at least the hot water part, this is the heater for you!

GE Tankless water heaters

While I was reading up on all the tankless water heater hype I ran across these statements:

“Care for your water heater should include evaluation of water quality. If the water exceeds the target levels provided in the table, you should treat or condition the water.

If you are in a hard water area, it is recommended to install a GE water softener prior to the water heater.”

Apparently scale buildup can ruin your tankless water heater and can even void the warranty!

Here are the maximum levels allowable without treatment to keep your warranty valid.

* Source: Part 143 National Secondary Drinking Water Regulations

MAXIMUM LEVEL

Total Hardness Up to 200 mg/L (12 grains)
Aluminum* Up to 0.2 mg/L
Chlorides* Up to 250 mg/L
Copper* Up to 1.0 mg/L
Iron* Up to 0.3 mg/L
Manganese* Up to 0.05 mg/L
pH* 6.5 to 8.5
TDS (Total Dissolved Solids)* Up to 500 mg/L
Zinc* Up to 5 mg/L

So if you live in a area with hard water you might want to get it tested before you purchase that tankless hot water heater… you might need a water softener as well.

Standard Gas and Electric Water Heaters
Like the other water heater sites, the GE site has no shortage of models. I really like the search functionality they have though.

You can search by fuel type, size in Gallons, length of warranty, and tank diameter. You are presented with all of the models that meet your criteria. Then you can sort them by price. Very handy if you are trying to choose between the 64 models they carry.

I Checked out what I think is the most expensive 50 gallon electric water heater… the Model #: SE50T12TAH

Here are the specs:

Brass drain valve
Heavy duty anode rod
Double 5,500 Watt Heating Elements
Stainless Steel Upper Heating Element
Energy Factor 0.94

Great energy factor and the 5,500 watt heating elements are the biggest I’ve seen anywhere for residential water heaters.

The GE site is useless for trouble shooting information.

I didn’t see anything else of particular interest, so it’s off to find another water heater site with storage and tankless water heaters to check out…

Bill the Hot Water Guy

Checking Out the Rheem Water Heater Web Site

Rheem Water Heaters

The first thing I noticed is that Rheem is number 1 on Google when you search for “water heaters”. They must be doing something right.

After looking over all of these hot water heater sites, they are getting pretty boring. However, Rheem does have a nice looking site and easy to navigate. There are some interesting things that I haven’t noticed at the other sites though. For instance, Rheem makes heat pump water heaters! Don’t run across them very often!

Heat Pump Water Heaters

Heat pump water heaters work just like your air conditioner, taking heat from the air around the heat pump and putting into the water. Since the heat pump is just moving heat energy from one place to another, it consumes much less energy than just heating the water up.

The warmer the ambient air temperature the more efficient they are, but if the ambient air temperature drops to around 40 degrees there just isn’t enough heat in the air for the heat pump to work effectively.

An energy factor of .9 is considered pretty good, where as the Rheem heat pump water heater has an energy factor of 2.0!

Solar water heating

Rheem seems to have a little of everything. They have several models of solar water heaters, both passive and active designs. They have all the specs and details you would ever want to know as well. And as you could assume, they have backup solar storage tanks with heating elements.

The Marathon water heater is interesting.

It’s a non-metal electric water heater. It has a plastic tank wrapped in fiberglass and other stuff. No metal to rust, and what they call a lifetime tank warranty.

It has two and a half inches of insulation which allows only 5º F heat loss in 24-hours! Other advantages include not needing an anode rod, so you don’t need to worry about smelly hot water. That rotten egg odor will not infect this tank.

It comes with a factory installed T&P (temperature & pressure relief) safety
valve and 4 feet of pipe insulation.


Tankless Water Heaters

Rheem also has a line of tankless water heaters. Typical sizes and energy factors comparable with the rest of the industry.

I did see a few features I wasn’t familiar with and have not seen with other models or brands, but then they might exist and I just haven’t run across them before.

They say they have a special cable to link two units together to operate as one for when you have for instance, really cold incoming water etc. The other related item is the ability to link up to 20 heaters using an optional manifold control assembly.

Probably wouldn’t need to do anything like that in a residential setting. LOL

Well that’s about all I’ve got for Rheem water heaters and the Rheem web site.

Later… Bill the Hot Water Guy

Bradford White Water Heaters and Web Site

Bradford White Water Heaters.

The next site I visited was the Bradford White water heater site. As with most of the other sites I’ve visited there are a zillion models of water heaters. The site seems easy to navigate and I had no trouble finding the residential products.

If you want to compare water heaters they have a great chart showing the energy factor for all their products including tankless water heaters. The chart makes it very easy to compare the energy efficiency of the various models.

I checked out the service manual for the Bradford White EverHot® Interior Tankless Gas Water Heater Models: IGI-180R-10(N,X) and IGI-180C-5(N,X) Manual 45095A

I must say they have a very extensive service manual. It does a very nice job of explaining how the models work. The theory of operation is very well explained and there are lots of timing diagrams, wiring diagrams, and illustrations. Reading through the service manual is like taking a course in tankless water heaters.

These heaters modulate the gas valve, the number of burners, and the water flow rate to obtain a stable output temperature even with changes in pressure from other appliances or faucets being turned on or off. It’s a technological marvel.

The tankless water heater trouble shooting section is even more impressive. Again, there are no shortage of diagrams illustrations and pictures to guide you. It’s extremely thorough and includes electrical trouble shooting and gas trouble shooting and anything else that can go wrong.

The only thing I found about maintenance was that sometimes you might have to use vinegar to flush the lime buildup out of the heat exchanger. Apparently the heater displays a message when it needs to be done.

Overall I liked the Bradford white site. I found it easy to use and full of useful information in a form that was easy to understand.

That’s if for Bradford White.

Bill the Hot Water Guy

A Visit to the Bosch Tankless Water Heater Web Site

At first glance the Bosch water heater site looks intimidating, but it only took me one click to find what I was looking for. On the left navigation column at the top under the heading “Consumer Information” I clicked on the link “Gas Products” and landed on a page with brief descriptions of the various gas water heater products that Bosch manufactures.

One thing I noticed right off is I don’t have to deal with PDF files! The Bosch web site quickly sends me to the page when I click on a link, and I usually find what I am looking for. Very nice.

The Model 2700ES Gas Tankless Water Heater was the first on the list, and so I clicked on the link to check out this model. The first thing I noticed was the statement that this model would supply 2-3 showers simultaneously! Wow!

I was certainly impressed. I immediately went to check the specs. Skimming the hype at the top of the page I noticed they claim a 20 year average life for the heater. I wonder if there is any evidence to back this up. Of course that doesn’t mean it did not need servicing or repairs during the 20 years, so it is of limited value at least to me.

The next section down the page is a large bulleted list of features, the first stating the water heater has an output of 7 gallons per minute! Enough for two good showers at once anyway… I don’t know about 3 though.

Now I am intrigued so I scrolled down to the technical stuff and discovered that it puts out 7.2 gallons per minute at a 45 degree F temperature rise. How disappointing! I mean it puts out plenty of hot water, certainly competitive with all the other brands, but I think the advertising is miss-leading.

After a more thorough look at the features and specs, I have to conclude that there isn’t anything very special about this gas tankless water heater.

I returned to the gas tankless water heater section and scanned down the products, and saw something that caught my eye. What I read was “The Bosch AquaStar Model 1600H incorporates a revolutionary hydro-generated ignition system, allowing the water heater to operate without a standing pilot, electricity, or a battery.”

So off I go to check it out. The features and specs page did little to enlighten me about how it works, all it said was no electricity needed, it generates it’s own. I wanted to know more about it so I went looking for some manuals.

On the manuals download page I was finally confronted with those dreaded PDF files. I first check the literature drop down box and downloaded the spec sheet. Nothing new there. Next I tried the Bosch Installation Manuals drop down box and selected the English version of the manual for the Model 1600H tankless water heater. They have the manuals in a number of different languages.

While reading the manual for the model 1600H water heater I made some interesting discoveries. How about the fact that there is periodic maintenance that needs to be performed on the heater.

Here is an excerpt from the manual:

“The GWH 1600 H requires periodic maintenance. The
below time maintenance intervals should keep the unit
operating for many years.

Every year
Inspect inlet water filter screen ( 5.2)
Inspect pilot assembly and flame ( 5.3)
Inspect burner assembly ( 5.4)
Every 2 years
Lubricate and clean water valve ( 5.2)
Every 3 to 5 years
Rebuild water valve ( 5.2)
Clean pilot assembly and clean or replace orifice”

The manual also states” Warning: Failure to perform recommended maintenance may result in complete failure of the unit over time. The warranty does not cover failures
due to improper or insufficient maintenance.

So maybe the maintenance should be done. The problem as I see it is that most people would not really want to do even the simple yearly stuff let alone rebuilding a water valve, or replacing a pilot assembly orifice.

I did find a drawing of the generator that provides the electricity to run the unit. No real useful information about it though.

I checked out the electric water heaters section and nothing new or different there. Electric tankless water heaters are pretty limited in usefulness due to the huge amount of electricity they require. Bosch doesn’t make standard tank type heaters, and only two models of tankless heaters.

They do have a couple of what they call point-of-use electric water heaters that have 5 or 6 gallon storage tanks, use 110 Volts, and produce about 6 gallons of hot water an hour.

Well I think that's about it for the Bosch Site.

Bill the Hot Water Guy

A. O. Smith Water Heaters, a Visit to their Web Site

Upon first landing on the A O Smith water heater home page I thought it was too busy might be difficult to navigate. I still think so.

I checked around and found they have a large confusing array of models with industry typical Energy Factors, tank sizes, and other features. I could find nothing new or exciting on this water heater web site.

I was quite frustrated by the site. It seemed anything worthwhile looking at was in the form of a PDF file, something I don’t care for. I had the impression that the site is more oriented to professional plumbers, not the everyday lay person.

No mention of prices. Typical warranties. Typical features, glass lined, anode protections, long-life 4500 watt heater elements, and they do have brass drain valves… at least that is something. If you have ever had one of those plastic drain valves break off you will appreciate the brass valves.

A. O. Smith, like the other water heater manufacturers claim a super duper self cleaning dip tube. As I have said before, there is no such thing. No dip tube can clean your water heater. Self cleaning dip tubes just don’t do anything.

They have a few tankless water heaters and models specifically for homes with hot water circulating systems and hydronic heating etc. I think it’s time I move on to the next hot water heater manufacturer on my list. Let’s see… Ah yes… this time it’s off to visit Bosch water heaters… well, their web site anyway.

Bill the Hot Water Guy

Residential Water Heaters – A Comparison Between Brands

Residential Water Heaters - Comparing Different Brands of Water Heaters
Water heaters can be a confusing topic, and there is quite a bit of competition between the various water heater manufactures to get you to purchase their brand.

I thought I might take a look at the websites for the various manufacturers to see if there are significant differences between the various brands of residential hot water heaters. Water heaters are a commodity product. Basically they are a tank of water with either a gas burner under them or electric heating elements inside of them. There isn’t really much to differentiate the water heaters from one manufacturer to another, with a few exceptions.


Comparing Brands

In the coming weeks I’ll examine the features of the basic residential models like 40 gallon gas water heaters, 50 gallon heaters, 40 and 50 gallon electric water heaters and I’ll take a look at the energy efficient models as well. I’ll go through the list of manufactures in Alphabetical order, and I’ll also include tankless models if they are produced by that manufacturer.

The manufacturers I will compare are American, A.O. Smith, Bosch, Bradford White, G.E., Marathon, Noritz, Rheem, Rinnai, State Industries, Takagi, and others.

Previous article comparing some brands of tankless water heaters.


Gas water heaters

All gas water heaters (storage type) have a gas burner, tank, flue, thermostat, drain valve, insulation, pressure relief valve, anode rod, dip tube, gas valve, pilot light, thermocouple, and tank insulation. That’s pretty much it for any storage tank type water heater.

There may be some gas water heaters that do not use a standing pilot light, but ignite when the thermostat calls for heat. I know there are commercial units with that technology available, but I am not sure about residential units. I shall find out and report back.

More about gas water heaters.

Electric water heaters

All electric tank type water heaters have a tank, electric heating elements, high limit switch, one or two thermostats, drain valve, anode rod, pressure temperature relief valve, and dip tube.

Electric water heaters are all pretty efficient as far as converting electricity to heat energy, the main difference in electrics being the amount of standby loss.

More information about electric water heaters.


Heat pump water heaters

I'll also be examining heat pump water heaters as I run accross them. They are very efficient at heating water but are pricy. More about heat pump water heaters... Heat Pump Water Heaters


Miss-leading statements

When I see glaring errors or miss-leading statements on the web sites I may very well make note of them as well. I find it very irritating when web sites miss-lead the visitors.


Stay tuned, American water heaters is the first water heater product review I will do, and I should have it up by tomorrow…

Bill the Hot Water Guy

Tankless Water Heater Savings

After my last blog, I got an email from a friend of mine, who is involved with the installation and sales of tankless water heaters. Here is what he wrote:

Bill,

I read all of your blog interesting but very negative on tankless, don’t agree with all of it but well written. where are the heating efficiencies, for example tank water heater is only 40 to 55 % efficient vs. 82 to 94% how about the clean water you get without all the junk from the tank, I have attached a picture from a tank that was only 10 years old, take a look. LOL. At the end what is more costly and important 10 to 20 sec. Additional delay of getting hot water and may be 2 gallons of water or the inefficiency of the tank water heater and the additional energy wasted and environmental impact. Oh well, I could go on. LOL

Al


So in response to Al’s email…

First off, who has a 40 to 55% efficient water heater?
I poked around on the internet looking at water heater efficiencies, and could not find any water heater with an energy factor of less than .56. Most were .60 or more. (I presume we are talking about the energy factor when we refer to efficiency.)

I took a look at the tankless water heater specs and I found that most tankless units had energy factors of about .82. The highest I saw was .92, but I didn’t spend a lot of time looking so I probably just didn’t come across those .94 units.

So before moving on, I would like to say that using 40 to 55 percent efficiency for tank type water heaters is on the extreme low side. 60 percent efficiency would be the most common storage efficiency from my limited research.

I visited the ACEEE – (American Council for an Energy-Efficient Economy) who I think you could say is an independent 3rd party. They have a comparison table comparing Life-Cycle costs for the various types of water heaters.

Interestingly they recommend looking for a gas storage water heater with a minimum energy factor of .63 and they state that the highest is .67. Quite a bit higher than 40 to 55%.

From their table, a conventional gas storage water heater with a EF of .60 has a yearly cost of $350, and a tankless water heater with an EF of .80 has a yearly cost of $262.

As you can see the difference in yearly energy cost is 350 – 262 = $88.00 a year, or about $7.33 a month. A tad more if the efficiency was .82 as I was finding.

For me, $8.00 a month is definitely not worth the potential problems associated with tankless water heaters, and the changes in behavior I would have to make, like giving up that “trickle” of warm water I use when I brush my teeth. I hate cold water on my teeth!

As for the pictures of the corroded old water heaters… here are my thoughts. First, since I usually drink cold water, I am drinking the water from the water main. Since the water passing through the water heater also came from the same source of water, then it must be even cleaner than the cold water if it leaves all that stuff in the heater.

All that sediment and those deposits are just minerals that have come out of the water as it was heated, and you consume those same minerals every time you drink the cold water. So I don’t see a problem.

By the way, in areas with high mineral content many of the tankless water heater manuals instruct you to clean out your heat exchanger periodically. It seems the hard water is hard on tankless heaters too! Cleaning the heat exchanger on a regular basis does not sound like something I would want to do.

Metlund D’mand systems, our main competitor and the big guys on the block as far as sales go state that the savings from a demand hot water system from reduced water consumption and reduced sewage fees amounts to about $150 a year for a typical home with a natural gas water heater.

Gee… that’s more than the tankless water heater saves to begin with. If Scottsdale Arizona is offering rebates of $200.00 for homes that install demand hot water systems they must feel that the wastage of water from residential hot water plumbing systems is significant.

If you are really concerned about environmental impact, then you should put a hot water demand system on your tankless unit and more than double the monetary savings and reduce both energy consumption and water wastage. Pumping and treating water and pumping and treating sewage consumes energy as well.

Subtract that extra gallon or two of water from the savings provided by the increased efficiency of the water heater, and environmentally the tankless water heater doesn’t look so good. Just my opinion of course.

So Al, perhaps I have miss-interpreted your numbers, perhaps you weren’t referring to energy factor with your efficiency numbers?

That’s all for today folks…LOL…if anyone reads this blog.

Bill

Electric Water Heater Problems - Storage Tank Type

Electric water heaters and the electrical problems they can have are today’s topic. The electrical system for an electric water heater is fairly simple, and easy to trouble shoot.

A typical water heater will have two heating elements and two thermostats plus a high limit switch.

Let’s start with the high limit switch. The high-limit switch is a thermal circuit breaker. When it gets too hot, it will trip, and a red button will pop out. So if suddenly you have no hot water, the first thing you might want to check is that red button. Push it in and see if that gets the heater going again.

There are two thermostats on a typical unit, one near the top and one near the bottom. The thermostat near the top of the tank is like a temperature controlled single pole double throw switch. That means it is either feeding electricity to the top heating element, or if it is off, it is directing the electricity down to the lower thermostat.

Understanding the operation of the heater will help in troubleshooting. Let’s assume that you just filled the bathtub with hot water, and so your water heater is basically full of cold water. Both the upper and lower thermostats will be turned “on” because the temperature will be below the set points of the thermostats.

Electricity will flow from the mains through the upper thermostat and into the upper heating element, through the element, and back into the mains.

Once the water in the top of the water heater has reached the set point on the upper thermostat, the upper thermostat will shut off the electricity to the upper thermostat, and send it down to the lower thermostat.

The lower thermostat is “on” since it has not warmed up above the set point. Because it is “on” it sends the electricity to the lower heating element and the electricity flows through the element and back to the mains.

When the water in the lower part of the electric water heater reaches the set point temperature of the lower thermostat it shuts off the electricity to the lower element and nothing else happens until the water in the heater lowers below one or the other set points.

Electric Water Heater Troubleshooting

If you have no hot water:

As I mentioned earlier, the first thing to try, in my opinion, is the high limit switch. Push the button and see if the heater begins heating the water.

If that does the trick, the next thing you need to worry about is why the high limit switch tripped in the first place. Did the water temperature get too high? If so why?

A defective upper thermostat that sticks in the “on” position is one thing that will cause the high limit switch to trip. Also a defective high limit switch could be the source of the problem.

Certain usage patterns (frequent small draws) can cause what is known as “stacking” where the water at the very top of the heater gets hotter than it should.

If the high limit switch button is not popped out or if pushing it has no affect, then it’s time to move on to checking the heating elements.

Testing Electric Water Heater Heating Elements

The first thing to do is of course; turn off the electricity to the water heater.

Next you need a simple ohm-meter. Like a cheap Radio Shack multi-meter.

Disconnect one of the two wires to the heating element and then read the resistance between the two heating element terminals.

The heating elements should have an electrical resistance of less than 50 ohms. You don’t have to worry about the amount of resistance though, it will either have some resistance, or it will have an infinite amount. If the needle moves, the element is ok. If it doesn’t, the element is burned out.

If the heating elements are ok, then it’s most likely a bad thermostat. Check and make sure none of the wires are broken or loose under a terminal.

Testing the Thermostats

The electricity comes into the water heater and goes directly to the high limit switch… usually the top two terminals on either side of the high limit switch. Normally the high limit switch is stacked above the upper thermostat.

The upper thermostat has one wire that connects directly to the upper heating element, and one wire that connects to the high limit switch. It has another wire that goes down to the lower heating element.

With a below set point temperature in the water heater, the high limit switch should be sending electricity to the upper thermostat, which should in turn be sending it to the upper heating element.

With the electricity still turned off to the water heater, check the resistance between the top wire that goes from the high limit switch to the mains, and the high limit switch terminal that leads to the upper thermostat. The resistance should measure zero. If not, the high limit switch is bad. (or the red button needs to be pushed in)

If it does read zero, then check the resistance between the terminal on the upper thermostat that connects to the high limit switch, and the terminal that lead so the upper heating element. It should read zero. If not, the upper thermostat is bad.

To check the bottom thermostat check the resistance from the lower thermostat terminal that connects to the upper thermostat, and the terminal that goes to the lower heating element. It should read zero. If not the lower thermostat is bad.

That’s it. You should have found the problem by now if it is electrical in nature.

Tankless Water Heaters Need More Love!

Tankless water heaters are all the rage now. Green is in and tankless heaters are considered greener than storage water heaters. They don't have standby losses and so are typically more energy efficient than tank type units.

Tankless Water Heater Savings

The dollar amount of tankless water heater savings is realatively small, and makes the payback iffy over the lifetime of the heater. Tax rebates are substantial though, and with the rebates many more home owners can expect to save enough money to more than pay for the unit. That is if there are no breakdowns.

Tankless units are more complex than storage heaters, and thus are more likely to breakdown and more expensive to repair. A service call or two can wipe out any savings realized by reduced standby losses.

Water Conservation and Saving Water

Tankless water heaters are not water conservation friendly. It takes them up to 20 seconds longer to deliver hot water since they must first heat the water and then deliver it to the fixture. A study done by the Australian government found that tankless water heaters typically take 10 to 20 seconds longer to deliver hot water than a storage type heater.

While you purge the cooled off hot water from the hot water pipes, you are running water down the drain. The longer the wait, the more water gets run down the drain.

Since tankless units require a minimum flow rate the keep the heater turned on of typically 1/2 gallon per minute to 3/4 gallons per minute, you will have to run the hot water at a higher flow than you might normally run it, and mix it with additonal cold water to get the temperature where you want it. A trickle of warm water will no longer be an option.

So for those people who for one reason or another run a small stream of warm water will have to make do with a much larger stream of warm water, again, wasting water.

Tankless water heaters are marketed with slogans like "endless hot water". Does this sound like a water conservation product? You don't buy a tankless water heater for saving water.

Tankless Water Heaters Need More Love... or At Least More Attention

Because tankless heaters are limited in the gallons per minute that they can heat to a specified temperature, one must consider the inlet temperature when deciding on a size. Too small, and the heater will not be able to meat your peak load demands and the temperature at the fixture will decrease as the flow rate is turned up at the faucet.

Too large of a model, and it will be difficult to adjust the temperature without the heater shutting off. And if you live where the water temperature varies widely from summer to winter, then you may have to change the outlet temperature setting on the heater as the seasons change.

Most gas tankless water heaters need to be plugged into a 110v outlet to power the electronics need to control the unit. Some units use the flowing water to spin a tiny generator powering the controls. Bosch water heaters have such a feature. So most units won't be able to supply hot water during a power outage.

I have seen a lot of chatter in forums about the need to clean the Bosch units frequently due to that tiny generator...

If you live where temperatures go below freezing you will have a new worry... damaging the heat exchanger. With a storage water heater freezing isn't going to happen. With a tankless unit you have to protect it from freezing as freezing will destroy the heat exchanger.

Some units come with a little built in heater for freeze protection... so much for eliminating standby losses...

Recirc Pumps and Hot Water Demand Systems

Most tankless water heaters will not work with a traditional hot water recirc pump. Read the warranty. Even so, most circulating pumps won't pump enough water through the heater to turn it on anyway.

Hot water demand systems are on the other hand ideal for tankless applications. They don't circulate the hot water, they get your hot water to the fixture without running water down the drain, and they can often get your hot water to the fixture more quickly.

However, most hot water demand systems still suffer from the "tiny motor" syndrome. Hot water circulating pumps typically range in horsepower from about 1/120 to 1/8 horsepower with around 1/40 kind of typical. Our competitors such as Act Metlund which makes several models, the S-50T, the S-70T, and the S-02T. The S-50T is not recommended for tankless systems, and the S-70T for systems with less than 100 feet of pipe. Compare the CP6000 with the Metlund D'mand System. Metlund VS Chilipepper

Our pump, the Chilipepper CP6000 with it's big 1/3 horsepower motor will run any tankless water heater on the market.

All brands including Rinnai, Takagi, Noritz, and Bosch work better when you combine them with a hot water demand system. See a comparison of the various models from the above brands. Compare Tankless Water Heaters

Point of Use Water Heaters

The most water and energy efficient plumbing layout is to have the heater a close as possible to the end use fixture. This can virually eliminate the wasted water, and eleminates the need for a pump. Often it is an ideal application for a small electric tankless water heater.

Tankless water heaters can provide you with "endless hot water" and can save you money, but there are other considerations, so choose carefully...

Bill the Hot Water Guy

Slow Hot Water

Today I would like to explore the topic of "Slow Hot Water".

First lets get something straight... there is no such thing as "Instant hot water" if you are referring to heating it! Even though you occasionally hear the terms "Instant water heater", when referring to tankless water heaters, technically there is no such thing. It takes time to heat water. More on that later.(maybe even my next blog actually)

Lets define what we mean by "Slow Hot Water". For our purposes slow hot water will refer to the speed at which hot water is delivered to the fixture where you are trying to obtain it, from the time you turn on the faucet.

For some of you the there is no wait... if you have a hot water recirculating pump or system for instance. A recirc pump that keeps the hot water pipe full of hot water eliminating slow hot water from your vocabulary. It's nice but expensive.

Some people will have a short wait... say less than 30 seconds, although if you are waiting for hot water 30 seconds can seem like 30 minutes, all the while running precious drinking water down the drain. Some people will have a moderate wait... say more than 30 seconds and less than 1 minute. An many have a long wait...over 1 minute. Running water down the drain for one minute will result in a waste of between 1 and 3 gallons or more, depending on the fixture flow rate.

Many of our customers have described waits of over 5 minutes! Wow. That is slow hot water!

What are the causes of slow hot water?

The first thing one thinks of is the distance from the water heater to the fixture. That can give you a rough idea, but can be very inaccurate. There are a number of reasons that the straight-line distance from your water heater to your hot water fixture is inaccurate.

Plumbing Layouts

Your actual plumbing layout plays a major role of course in the speed at which you get your hot water. The actual pipe length will depend on whether your plumbing is located in an Attic, under a crawl space, in the walls, or under a slab.

Another factor is what type of piping material is used, soft copper, hard copper, galvanized pipe, or plastic pipe? Since some of the hot water cools off from contact with the pipe as it travels to the fixture, the pipe material and weight are important variables as well in how long it takes.

Your plumbing layout quite possibly does not follow a straight line route. Most copper and galvanized pipe residential plumbing systems follow the joists and beams and make sharp right angles to get from point A to point B.

With these things in mind lets take a look at the plumbing layout for a house with the piping primarily in the crawl space. The water heater is a gas model on a stand 24" off the floor of the garage. The pipe will begin as 3/4 inch diameter hard copper pipe, and transition to smaller branch lines of 1/2 inch dia.

The pipe would exit the top of the water heater, using right angle elbows it would extend up a foot or so, and run down the side of the heater and into the crawl space below the floor. By this time you have already used 6 to 8 feet of pipe and you haven't yet started the journey to the fixture. That journey can consist of a variety of changes in direction through the use of elbows and T fittings, and the pipe diameter can be reduced to the 1/2 inch dia. for branch runs from the major hot water feed to the individual fixtures.

The diameter of the pipe is chosen to provide the minimum flow rates for the various fixtures. The flow rate is different for different types of uses. For instance, a kitchen sink fixture requires a higher flow rate than a bathroom faucet, but not as much as a bathtub fixture.

By not using a plumbing layout with a straight run from the heater to the fixture, 15 or twenty extra feet can be added to the run if it traverses several rooms. So the pipe length may very well be substantially longer than is at first apparent. Every fitting also adds to the virtual length of the pipe. (Elbows and direction changes cause a larger pressure drop than straight pipe.)

Pipe Material and Pipe Insulation and Hot Water Tunneling

As the heated water flows through the pipe, it gives up some of its heat to the pipe material. As much as 50% of the wait time is caused by the hot water being cooled off by the cold pipe as it travels through the plumbing. To make things even more interesting, the actual speed of the water through the pipe affects how much heat gets transferred. When the water is traveling at higher velocities it gives up less than the expected amount of heat because most of the HOT water is traveling through a small channel through the not-flowing cooled off hot water in the pipe.

The hot water "tunnels" through the center. With slower flows the water moves more like a bullet nosed column of hot water pushing the cooled off hot water out ahead of it. Therefore, speeding up the hot water flow rate results in a even faster than expected arrival of hot water due to the tunneling effect.

Other interesting observations are that some plastic piping such as PEX can lose more heat than copper or galvanized pipe to the ambient air space around it; another unexpected result. Insulating the pipe reduces the heat loss from the pipe and as expected this time, can reduce the wait time for that slow hot water.

Pumping the same number of gallons per minute through a smaller diameter pipe causes an increase in the velocity of the water and a shorter wait time. However, since smaller pipes have larger pressure drops, an undersized pump motor could cause an actual increase in wait time if a pumping system is being used.

Saving Water with Low Flow Fixtures or Not!

Saving water is always a priority these days, but low flow fixtures can cause a huge waste of water. Many people have fixtures with flows of down to 1 gallon per minute. With flow rates that low, the water travels in the "bullet" mode and takes longer to reach the fixture, causing more water to be run down the drain.

Electric Tankless Water Heaters (and gas)

Tankless water heaters, especially the electric tankless units, take time to heat water. They are not instant. For the water to reach full temperature it must travel completely through the heat exchanger which takes time. An Australian government study stated that tankless water heaters typically took 10 to 20 seconds longer to get hot water to the fixtures than tank type storage water heaters.

Obviously adding 10 to 20 seconds to the wait time does not help the slow hot water problem.

So there you have it, a fairly comprehensive discussion of why the hot water is slow. You know what to do about it, get a Chilipepper pump of course. A must have accessory for any water heater storage or tankless, electric or gas, or even solar, oil burner, wood burner or other heater as well! Yes, even heat pump water heaters!

Until my next blog... Bill the Hot Water Guy