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Using a hot water heater to heat the home

They say Necessity is the Mother of Invention.
I currently have a Gas fired Boiler for a Radiant Baseboard system throughout my Tri level home. The Gas bills in my region are astronomical. I purchased a 40 Gallon electric water Heater and through a series of isolation valves mated it to my boiler. By turning a few valves I can use the electric Water heater or my Gas fired boiler. The theory is I should be able to get 155 degrees of water out of the electric water heater. I’m hoping I can use the electric water heater through 75% of the season. And when the temperatures drop to far down that it can’t keep up, I will switch to the gas-fired boiler, which can provide 180 degrees of water temperature.

My question to you is will I see a savings using the electric water heater versus the gas-fired boiler? Do you think the system is feasible? Currently I have a few issues with air in the lines I have to work out before I fire it up. Do you think I need an Expansion tank in the line like the boiler has? I would appreciate your opinion on this project.
Thanks Big Joe

Re: Using a hot water heater to heat the home

I don't get it, could you possibly explain how you did this?

Re: Using a hot water heater to heat the home

I agree with your theory after all there are electric radiant heating systems out there. However those are sealed systems re using the same water which is purified to keep it from degrading the components. To introduce hot water from a water tank wouldn't be as purified and the sacrificial rod in could pass even more damage into your radiant system. In addition, your system is designed to recirculate the water and a water tank isn't designed to accept that water back and reheat it nor will it be able to handle the sediments and "boiled down" minerals that could be in your system. Especially if you end up with a compromised water source such as a malfunctioning (hole in the) pipe that supplies water to your water heater.

Here's the next flaw in your plan. The electrical heating units for radiant heating are equipped to handle the constant on and off demanded by the system. The hot water tank will burn out a lot faster than you would expect subjecting it to the same on and off constantly all day or night.

Electric water heaters are slower to heat water and a lengthened time of losing water that would be heated will lower the temperature of the water going through the system as much as 25%.

Finally, if you are concerned with the expenses of running the heating source designed for your system I would suggest you check into switching to a more economical fuel source completely rather than messing with the system as it is.

If you would like to have alternate heating sources in problematic areas then install electric radiant in those areas to share the load.

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