Can I use a 50 gallon hot water heater to heat a baseboard heater?
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Since you can use a boiler to heat baseboard hot water for heating , can I also use a 50 gallon electric hot water heater to heat baseboard hot water for heating? The hot water heater would only be used for heating, basically a closed system. A 50 gallon electric water heater has a first hour delivery of 62 G.P.H. Thanks…Glenn
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Replies
Glenn,
I love easy questions. Yes.
Martin: This thought has occurred, I am sure, to 100's of us. Wouldn't the answer depend a great deal on btu demand? If the load is "fairly large", like zone 6 and up, do you think an electric water heater could keep up?
Yes, this is an easy question, but the answer is almost always NO.
A 50 gallon electric water tank with dual 4500 watt elements, running 24/7 can put out (assuming 100% efficiency and no line losses) about 30,000 BTU/hour. Unless you have a small, very well-insulated house, or live in a mild climate, that's not likely enough for the winter design temperature.
Also, electric water tank heaters have the shortest life of all the water heating appliances. They are cheap to buy and install, but expensive to operate over the long run. And electricity, in most places, is a very expensive way to heat a house.
If this a closed system than you need a pump to run the water through the baseboard, right?
You have a thermostat in the tank to maintain a certain temp. Can you add another thermostat for room temperature, or is this a manual system?
Does a closed system add pressure on the tank? Will the pressure relieve blow often?
J Chesnut,
A water heater, like a boiler, has an aquastat. Just because an appliance has an aquastat, doesn't mean that a wall-mounted thermostat can't be used to control a circulator.
Circulating water from a water heater to a radiator does not appreciably change the pressure of the water in the water heater.
We heated a 600 sf artists studio here in North Carolina off of a 20 gallon under counter electric water heater with hot water to spare for a shower and kitchen. we used a radiant slab and the walls and roof were well insulated and reasonably airtight (spray foam).
I hated to do it because of the environmental impact of electricity from coal power plants but a strange monopoly situation with the propane supplier allowed them to demand exorbitant fee for giving us a propane tank that killed the plan to use a propane fired demand water heater to do the job.(We would have had to buy out their contract on two other tanks on the property in order to get release to use a different supplier) The energy usage of the structure was obviously very low and the power bills were quite reasonable.
We ran the temp on the water heater up fairly high (140 or so) with a single 1,500 watt element and stepped it down for bathing with a tempering valve. We mixed down the heat as it went into the floor with a flat panel heat exchanger and two Taco 006 pumps controlled by a wall mounted electric heat T-stat. The entire system, water heater, pumps manifold and heat exchanger in a rectangular sheet metal drain pan) fit into the 2' x 2'6" wasted inside corner space under the kitchen counter next to the kitchen sink.
Cost was about $200 for the water heater, $300 for the stainless steel heat exchanger, $130 each for the two brass pumps, some brass nipples and a check valve, a fifteen dollar t-stat and a $130, roll of 500' x 1/2" PEX. maybe a grand all told plus the labor,
Walking into that cabin in the middle of the winter, priceless.
well a 50 gallon water heater be anough to heat 1800 sq home,raident heating
Anonymous,
It depends on:
1. Your climate (that is, your design temperature);
2. Your insulation levels;
3. Your windows sizes;
4. Your window specifications;
5. The orientation of your windows;
6. Your air leakage rate.
In other words, do a heat loss calculation and determine your Btu/hr heat load at your design temperature (for example, -20°F, or 0°F, or 20°F, depending on where you live).
Something I'm not getting here - why use an electric resistance coil to heat water to pump around a baseboard when you could just have electric resistance coils in the baseboard itself and avoid the standby and mechanical losses?
Probably because the baseboard radiation is already in place and he just needs something cheap to supply heat.
Anywho, hydronic baseboards don't have that sizzled dust odor of electric resistance heaters.