Supercharge Your Tankless Water Heater –
Get Fast Hot Water and Be Green!
Tankless water heaters save energy, but not water, they waste water
While it’s true that tankless water heaters save
energy and can provide an endless supply of hot water, it’s also true
that tankless units take longer to get the hot water to the fixtures.
Since a tankless heater needs to heat the water before it can deliver
hot water to you, you have to wait longer. The only way to get the hot
water of course is to run the faucet. So while you run the faucet and
wait, you are dumping gallon after gallon of pure clean water down the
drain. Water that required energy for pumping and treating it. Pumping
and treating the water uses energy which in turn means green house
gasses being released into the atmosphere.
The heater can be pictured as a long piece of pipe
coiled up and placed over a fire. As the water flows through the pipe
it gets hotter. In order to reach full temperature it has to stay in
the fire for a certain period of time. It will take longer if the water
starts out colder. If you speed up the flow of water it will get
cooler, unless you add more fire. With the old storage heaters the tank
full of hot water is ready to go the moment the faucet is opened so you
get your hot water faster.
With tank type heaters what has been done in the
past to both speed up the delivery of hot water and eliminate running
the water down the drain while you wait is to create a loop in the hot
side of the plumbing so you can pump the hot water around the loop,
keeping the pipe full of hot water. That way when you turn on the
faucet you get instant hot water every time whenever you want it. It
works great with a tank type heater except for the fact that it uses a
whole lot of energy keeping the piping warm.
But you can’t do that with the tankless unit
because tankless heaters turn on when they detect water flowing through
them. Usually it takes ½ gallon per minute of flow or more to activate
most tankless heaters. Most circulating systems don’t produce that much
flow. If they did, then the water heater would be on all of the time.
Using a standard circulating system with a tankless heater will void the
warranty in almost every case anyway.
There is another type of hot water delivery system
called a demand system that will work just fine with tankless water
heaters. The way it works is a small pump is installed under the sink
furthest from the water heater. When you want hot water you press a
button and the demand system pumps the water at high speed from the
water heater to the fixture. The system has a temperature sensor
monitoring the temperature of the water, and when it senses an increase
in temperature it shuts off the pump. This prevents hot water from
entering the cold water lines.
Since the pump only runs for a few seconds at a
time it uses very little energy. Typically it uses less than $1.00 per
year in electricity. It doesn’t use any more heat energy than a
standard plumbing system. It saves 100% of the water normally run down
the drain waiting for the hot to arrive.
Demand systems are suitable for use with tankless
water heaters since the pump only runs for a short time, and will not
void the warranty of the water heater. Not all demand systems have
strong enough pumps to run tankless water heaters though, so you should
check with the manufacturer before you make the purchase.
Metlund makes a demand system they call a D’mand
system. They have several models, and I think the largest model has a
strong enough pump to use with a tankless heater. Metlund’s d’mand pumps
range from 1/40 horsepower for the smallest to 1/8 horsepower for the
biggest. Chilipepper makes a demand system, and they only make one
model, the CP6000. The CP6000 has the most powerful pump of any system
on the market, (approximately 1/3 horsepower) and will work with any
tankless water heater.
Another reason for using a more powerful pump is
that the more power the pump has the faster the hot water will arrive at
By combining your energy efficient tankless water
heater with a hot water demand system you get the best of both
worlds…you are energy efficient and you conserve water. It’s a great
feeling to know that you are doing your part to protect the environment
and conserve our natural resources every time you use hot water.
Chilipepper Sales 1380 Greg St., # 221 Sparks Nevada, 89431