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.

Instant Hot Water! – Home Improvement Idea

There are a lot of home improvement ideas floating around out there, and every one has his own opinion of what a good home improvement idea is. Well I think instant hot water from your fixtures is a great idea! It will save you not only time, but thousands of gallons of water, and it can save you energy too.

Saving water and energy means you are reducing your carbon footprint and taking steps to going green. Help yourself and help our planet at the same time.

Probably most people don’t think about plumbing when they think about home improvement projects. After all, the plumbing layout has been already implemented and so changing the plumbing system into a green system by improving the plumbing layout is an unlikely project.

However, fast hot water is easy to obtain by using a hot water demand system.

Few would argue that it’s no fun standing there waiting for the hot water to arrive at the fixture. You stand there and watch the water run down the drain. But you don’t have to; you can install a hot water demand system in a single afternoon. Demand hot water system pumps can be obtained for less than $200, making it a fast and inexpensive home improvement idea or do-it-yourself project.

A demand hot water system delivers the hot water from your existing water heater at a higher flow rate than your faucet can deliver. That way the hot water gets to the fixture more quickly reducing your wait time.

More importantly, you don’t run water down the drain while you wait. When you turn on the fixture you get instant hot water. The demand pump connects between your hot and cold water lines under the furthest sink from your water heater. When you want hot water you “demand” it by pressing a button.

The pump starts up and send hot water to the fixture in seconds, returning the cooled off hot water that was in the hot water pipes back to the water heater through the existing cold water lines. When hot water reaches the pump, it shuts off. Now when your turn the spigot you get instant hot water.

Some models of demand hot water systems connect up to your plumbing with faucet supply hoses just like the ones already under your sink.

Hot water demand systems can also operate with tankless water heaters unlike traditional hot water recirculation systems. Just make sure the demand hot water system you purchase is powerful enough to turn on your tankless water heater. Some models like the Metlund S-50T and S-70T don’t have much power, and won’t turn on many models of tankless water heaters.
These quick hot water systems, at least the demand systems, use very little electricity since they run for such a short time, and only when you demand it. Typically they consume less than $2.00 per year in electricity costs.

With all the benefits of saved time, saved water, saved energy and reduced carbon foot print and the small initial investment, a hot water demand system should be in nearly every home. Don’t wait any longer, install a hot water demand system today and get instant hot water when you turn on your fixture – a great home improvement idea!

Hot Water Recirculation – Instant Hot Water Systems Explained

Hot water recirculation systems are often referred to by a variety of names, all meaning pretty much the same thing. Recirc pumps, recirculation pumps, recirculating pumps, and circulation pumps are all the same.

In our context they all refer to the practice of circulating hot water through your plumbing so that you have quick hot water and don waste water running it down the drain while you are waiting. As with most good things there are trade-offs with hot water recirculation systems.

First, let’s examine a basic recirculation system and get familiar with how it works. The system consists of the water heater, a pump, and a loop of pipe coming from the outlet of the water heater, going from sink to sink in a looped fashion, and returning from the last sink back to the pump which has its outlet connected to either the inlet to the water heater or to the drain valve.

Recirc pumps
Often called recirc pumps, as well as recirculation pumps etc. the hot water circulating pumps are designed to slowly circulate the hot water through the piping at a low velocity. There is no need for high flow since a nice low flow still keeps the water piping hot through the entire system. High flow rates run continuously can also lead to pipe erosion and eventually require replacement of the pipes.

Instant Hot Water

As you can see, such a system will provide you with nearly instant hot water. This can save tremendous amounts of water that would have been run down the drain while you waited for the hot water to arrive at the fixture. The penalty you pay is in the cost of the energy consumed keeping your giant radiator system hot.

The water heater has to fire up more often and for longer to keep the temperature from falling as the heat energy is let loose on the environment.

You can minimize your energy costs by putting the pump on a timer so that it only runs when there are people around that may want to use hot water. Leave it off late at night and during the day if no one is home during the day. It still wastes a lot of energy but you can easily cut your losses in half in most cases.

The downside is of course, if you want hot water when the pump is not running you will have a lengthy wait. If you don’t have a length wait you probably didn’t need a hot water recirculation system to begin with.

Another way to control the traditional hot water recirculation systems is with temperature control. Have the pump turn on when the temperature drops to some pre-set value, like 100 degrees, and when the temperature reaches 120 degrees turn the pump off. The temperature sensor is called an aquastat, and usually clamps onto the hot water pipe near the pump.

Since you still have piping full of hot water for long periods of time you are still wasting a lot of energy.

If you do have a hot water recirculation system you should insulate all of the hot water piping to minimize the heat loss.

Tankless Water Heaters

Tankless water heaters generally don’t work with hot water circulating systems since for one thing most hot water pumps don’t produce enough flow to turn on tankless water heaters. They usually require at least ½ gallon per minute to operate.

Hot water recirc systems also cause the water heater to cycle on and off frequently since there is no tank for storage. With many brands of tankless water heaters a hot water circ system will void the warranty.

Tankless water heaters take longer to deliver hot water than tank type water heaters and so it’s too bad hot water recirculation systems don’t work with them.

Well that’s about it for hot water recirculation systems, a water heater, a pump, some hot water piping and a few faucets. Don’t forget the pipe insulation.

Bill the Hot Water Guy

Easy Home Improvement Project – Go Green with Your Plumbing

Looking for an easy project that you can do to improve your home? How about going green with your plumbing? By making your home more energy efficient and water efficient you’re are improving the resale value of your home and providing yourself with reduced water and energy bills and added convenience.

If you have to wait for an extended period of time to get your hot water you are a good candidate for one of the many instant hot water systems. Most don’t really provide you with “instant” hot water, but can considerably reduce your wait time, and can even nearly eliminate running water down the drain while you wait.

There are a couple of retro-fit friendly instant or more appropriately fast hot water systems that are easy to install with no major changes required for your plumbing layout. Although these fast hot water delivery systems install under the sink, they are not to be confused with under the sink water heaters. They make a good one-afternoon home improvement project for almost any skill level. If you can change a supply hose you can install one of these systems.

There are basically two types of systems, luke-warm circulating systems like the Laing Autocirc1, and the RedyTemp, and hot water demand systems such as the Metlund system and the Chilipepper pump.

The warm water circulating systems are small pumps designed to circulate the water from the water heater through the piping and on back to the water heater. When the pump senses the temperature has reached the lower set point, about 90 degrees, then it turns on until the pump senses the upper temperature, about 100 degrees, when it shuts off the pump. The system does this over and over keeping the water in the piping warm.

You end up paying for all that heat energy it takes to keep the piping warm. You also no longer have cold water in your cold water pipes. Now it’s warm.

The second type of system is known as a hot water demand system, and the pump only pumps the water to the fixture when you demand it by pressing a button. Hot water demand systems make a better home improvement project because they provide even more convenience and use less energy than the recirculating systems and will really add to the green aspects of your plumbing system.

Again, the pump mounts under the sink and is easy to hook up. With the demand system when the hot water reaches the pump the pump shuts off so you don’t end up with hot water in the cold water pipes.

Demand systems don’t run very long or very often so they typically use about $1.00 per year in electricity, and you don’t run any water down the drain waiting for hot water. They don’t use any more energy than a system with no pump since they only fill the pipe between the water heater and the fixture, just like if you ran the faucet.

If you’re looking for an easy home improvement project you can complete in a weekend, one that will add value to your home, and will provide you with lasting benefits like faster hot water, water savings, and energy savings, then install a demand system today!

Hot Water Recirculation System? Replace it with a Demand System!

Many residential single family and multi-family homes built in the past have full time hot water recirculation pumps and systems installed. This no doubt saves a whole lot of water, but it also wastes a tremendous amount of energy.

Hot water recirculation

Recirculating systems were typically used in larger homes, say 3,000 square feet and up. Long pipes mean long waits, and if you could afford a big house you didn’t want to have to wait forever for the hot water to arrive.

Full time recirculation systems slowly circulate the hot water through the hot water piping keeping the water in the pipes hot for instant use. Turn on a faucet and within a second or two you have hot water. It’s a great convenience, but there is a penalty to pay.

Wasting energy

Your hot water plumbing becomes a giant heat exchanger causing your water heater to fire more often and longer. Not only does this waste a huge amount of energy, but it substantially increases the wear and tear on your water heater.

Even if you heavily insulate the pipes and put the recirc pump on a clock timer, you still end up spending a lot of money for that wasted energy. It’s not helping your carbon footprint either.

Hot water demand systems

A demand hot water system on the other hand will still save you thousands of gallons of water each year, and it won’t waste any energy. Demand pumping systems typically use about $1.00 per year in electricity to run the pump. This is because the pump only runs for a few seconds and only when you really want hot water.

With a demand system, you simply push a button when you want hot water, and that starts the pump. The pump sends the water to the fixture at a faster rate than if the faucet was just run. When the hot water reaches the fixture, the pump shuts off, and when you turn on the faucet you have instant hot water. No water was run down the drain.

Installation is easy. Simply remove the old pump and replace it with the demand pump. Buttons can be hard-wired from the points of use, or wireless switches can be used.

You will still save water, and you will save energy and extend the life of your water heater. Best of all you will feel good every time you use your hot water knowing that you are doing your part to reduce global warming!

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

Saving Water and Saving Energy - Human Behavior

Saving water and saving energy in a residential home setting, is largley a behavioural problem. If you observe how people use thier water for instance, you can spot wasteful behaviors all over the place.


Yard and lawn watering behaviors that don't save water

There are the obvious wasteful behaviours, such as watering the lawn at the wrong time of day, or over watering, and even watering the sidewalks and streets. The behavior in these cases is I guess, lazyness. All are easily corrected, but require someone to take the corrective action.


Low flow fixtures VS. behavior - To save water and energy

Once of the most often used water conservation methods or device is the low flow fixture. Low flow fixtures are a double edged sword. They can provide significant savings, and in turn can inadvertently cause a lot of waste.

For example, low-flow fixtures limit the maximum flow rate available from the fixture. This translates to lower water velocities through the pipe, and thus require a longer wait for hot water. However, a common reaction for those people who have very long pipe runs, is to turn on the hot water in the shower and go do something else while the shower gets hot. When they return, they often return to find hot water running down the drain.

Depending on how long the water ends up running before the human returns to use it, the savings in water is negatively impacted, and can even end up wasting more water than if the low flow fixture had not been used to begin with.

In the previous scenario energy is also being wasted. The cost of heating water is much higher than the cost of the water being heated. Running hot water down the drain is very expensive in terms of money savings... or loss!


Save Water - Behaviors in the Bathroom

Studies have shown that 80 percent of the time a typcal hot water draw occurs at a bathroom sink, the hot water doesn't make it all the way to the fixture. Most of us are guilty of this behavior... impatience... we turn on the hot water to wash our hands and we can't wait for the hot water so we start washing, only to finish about the time the water starts to warm up.

If you don't end up using the hot water, and all you've done is filled the pipe with hot water which will then cool off, then you have essentially wasted the energy. Better to not use the hot water faucet at all.

There are a whole lot of behaviors in the bathroom that can lead to wasting water, things like letting the water run while you brush your teeth, especially warm or hot water, running water whle you shave, lingering in the shower, etc.

The laundry room and saving water and energy

The obvious answer to saving water in the laundry room is to use the smallest load setting possible while still having enough to get the clothes clean. Using cold water instead of warm or hot saves energy as well.


Save water in the kitchen

The kitchen also suffers from human behavior caused water wastage. Single handeled faucets along with human habits are a contributor to energy wastage. If you don't swing the handle all the way to the left when drawing cold water, then you are drawing some hot water as well... a waste of energy.

Running the hot water to get your dishwasher really hot water is wastefull of water, running water to rinse dishes thouroughly, even hot water, when your dish washer doesn't need pre-rinsing, etc.

Save water and be energy efficient

There is one solution to several of these water saving problems... a demand hot water system of course. In the bathroom it will save energy and water by eliminating running water down the drain while you wait for hot water to arrive as discussed earlier.

In the kitchen it can eleminate the wasted water that you run to get hot for your dishwasher etc.

When you really do need hot water you get it more quickly and without wasting any water which saves you additional energy. It's the perfect companion for low flow fixtures!

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

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

All About Hot Water

Ok, this is my first official blog. I was hesitant to start a blog since I wasn't sure I could come up with something to blog about often enough to make it worthwhile, but I figured out what I could do if my brain was too slow.

Publish some of the more interesting emails we get from potential customers, and my response to them. We get all kinds of emails from people who don't understand one thing or another, and I have to assume a lot of them don't read either. If they did they would have found the information they were looking for right on the front page in many cases. LOL Go figure.

Hot water... the last frontier.

In a way hot water is like the final frontier. It seems like every other way to conserve energy and water has been covered many times over. Low flow everything from toilets to shower heads and high efficiencty appliances like dishwashers and washing machine are now common place.

Now maybe it's time to address the enourmous amount of wasted water and energy that could be saved from our hot water plumbing distribution systems. Todays large homes tend to have long and large diameter hot water piping which leads to a great deal of water being run down the drain, and heat energy slowly disspating from the pipes full of hot water sitting there cooling off.

Conservatively a demand hot water pump like the Chilipepper can save a typical family of four over 10,000 gallons of water per year. With over 50 million single family homes in the United States, if everyone had one of these systems we would save over 500,000,000,000 gallons of water per year. That doesn't count condos apartments and commercial uses if applicable.

It's very inexpensive and typically will pay for itself in a couple of years. In addition, the home owner gets his hot water faster which is always nice.

The demand pumps are easy to install and use very little electricity, usually less than $2.00 per year to operate. These systems even work with tankless water heaters, which is good since tankless water heaters take 10 to 20 seconds longer to get hot water to the fixture which means running more water down the drain.

Well, I think thats about it for my first blog post...

Bill the Hot Water Guy