I have a 15 year old dx system that is in need of repair. I have an A-coil leak and I'm getting that replaced along with replacing my old no longer funtional desuperheater. I have already bought the new ECM desuperheater. After speaking with the manufacturer. I gather this electronicly controlled DSH will probably operate more often than my old tempering valve controlled DSH. Currently the desuper heater is hooked directly to the hot water heater via faucet and HW line.

My question is "Is it really worth it to add a second hot water heater as a preheat tank for the water heater. As in heat tank #1 (no elements) with desuper heater and use that to feed cold water side of water heater #2(electric elements).

I found an earthlinked dealer who is going to do the repair and install for me as it is currently built. I wanted to establish a relationship with a dx vender for the future as my system has not been made in years.

I can do the plumbing work to add the preheat tank myself after the fact. I have a deep cold well. The dealer felt that I may get some advantage from the preheat tank even if the DSH is not running in heating mode. Because of the well it would likely heat the cold water to room temp even without the DSH running. A 15-20 degree increase over well temp. We don't use alot of hot water these days as it's just me and the Momma Squatch these days. No kids at home. Our electric rate has doubled in the last year or so because of dereg fiasco.

I would appreciate any opinions you folks can offer.

Use the buffer tank. If you want to save a buck or two tell the installer you'll buy it and plumb it in.
Going without could cost you more than you save.
Good Luck,
Joe

Thanks, I was going to add the buffer myself if I do it. The system originally had a DSH without the buffer tank. My circulater pump only runs when refrigerant is above 120 deg. With the old desuper heater I could see the difference in the bill(decrease) when it was in use (AC only). The circuitry in the geo only let it run in AC mode originally.