Home Heat Using Hot Water Heater???

[royroy]

In helping my son with his new (to him---about 10-15 y.o. in house years) I asked him how his heat pump was working. He insisted it was only an A/C unit. (Outside Unit is Trane XE100, MOD: TTR036C100A3, SER: P2645H9FF, Built in 1999. Did not have my coveralls so I did not go up and look at the air-handler) Then he showed me in the garage where the ouput from his hot water heater is split and one line runs through what is obviously a small circ pump (the return line connects to the input of the heater). He says this is his heat (He bought this in July). Anyhoo, have never seen such a set-up but I'm willng to learn. I assume it has some sort of heat exchanger(s) buried somewhere in the A/C system (air handler???) To me, it looks kind of inefficient and very $$$ to operate. Any advice, links to descriptions on installation, operation, maintenance of such a system, or whatever else might be enlightening? TIA Roy

[Speedy Jim]

As long as gas prices are competitive (w/electric), it's a good system. He must live in a mild temp area, cuz the water heater has limited output. If the heater has to run long periods for heating, its life will be shortened from the typical 10yr lifespan. But replacement heaters are way inexpensive compared to a furnace.

Jim

[PrecisionMachinisT]

Could be a desuperheater.

These provide "free" hot water by rejecting waste heat to the water heater when there is a need instead of all going to the outside air whenever the A/C unit is running.

[HeatMan]

WH's are not suggested for home heating applications unless it says so on the label.....

I'd have a problem with the stagnation of the water too, during the off season.

[SQLit]

More likely an hot water return pump so that the hot water is always at the farthest faucet. But I can not see if from here.

[rck]

I lived in an apartment in Philadelphia that used the water heater for heat. However, it was no ordinary hot water heater. In addition to providing household hot water, it had a set of coils with separate output circulated to a heat exchanger which heated air which was then blown through ducts. The hot water for household use never came in contact with the water in the heater piping.

Bob