EcoRenovator - View Single Post - My next project natural gas tankless hot water heater.

stevehull · 12-30-13, 01:01 PM

Ok, need some help here on what to do re water heater (fits right in with this discussion).

Old home, now for sale, has the 25+ year old tankless Aquastar 170. Next year, we are tearing down old farmhouse where we live now and rebuilding on foundation. Lots of reasons, but cast iron pipe plumbing is clogging up, old electricity/wires in house are bad, roof needs repairs, etc, etc, etc. We knew it was temporary housing when we moved here.

Anyway. I do heat/cool former and present farm house with open loop GT heat pump. In the summer (May - September), I have a loop from desuperheater that essentially fills a 55 gal electric water heater to capacity (120 F) each day (old farmhouse). I turned off one element as I super insulated this "preheat" tank. At least that is what I called it before I found out GT heat pump/desuperheater would fully heat it up in the summer.

I will move these (heat pump/water heater tank) out of old farmhouse and will reinstall in home when rebuilt. In meantime, while rebuilding, we will live in mobile home on property (also heated/cooled with GT heat pump and use an electric water heater storage tank for stored summer desuperheater water).

For the other six months, I have used electric resistance heat for this water, but I kick myself as this is one of the poorest uses of 1 phase 240 VAC. Clearly, in the mid winter, like now, I get almost no hot water from the desuperheater and use resistance heating for hot water.

I do have (and will have) propane so I could easily plumb in a tankless water unit in the rebuilt farm house, after the pre heat tank, to fire up if there is not enough hot water (turn off tank resistance elements).

My thinking is that my ROI is probably best just using the existing tank. However, we have LOVED the efficiency and use of the Aquastar as it supplied gobs of endless hot water. When we had three young children, this tankless water heater was a wonder to behold.

But it is hard to complain about essentially free hot water from the desuperheater for 1/2 of the year . . .

Thoughts?

Steve

12-30-13, 01:01 PM	#16
stevehull Steve Hull Join Date: Dec 2012 Location: hilly, tree covered Arcadia, OK USA Posts: 826 Thanks: 241 Thanked 165 Times in 123 Posts	Ok, need some help here on what to do re water heater (fits right in with this discussion). Old home, now for sale, has the 25+ year old tankless Aquastar 170. Next year, we are tearing down old farmhouse where we live now and rebuilding on foundation. Lots of reasons, but cast iron pipe plumbing is clogging up, old electricity/wires in house are bad, roof needs repairs, etc, etc, etc. We knew it was temporary housing when we moved here. Anyway. I do heat/cool former and present farm house with open loop GT heat pump. In the summer (May - September), I have a loop from desuperheater that essentially fills a 55 gal electric water heater to capacity (120 F) each day (old farmhouse). I turned off one element as I super insulated this "preheat" tank. At least that is what I called it before I found out GT heat pump/desuperheater would fully heat it up in the summer. I will move these (heat pump/water heater tank) out of old farmhouse and will reinstall in home when rebuilt. In meantime, while rebuilding, we will live in mobile home on property (also heated/cooled with GT heat pump and use an electric water heater storage tank for stored summer desuperheater water). For the other six months, I have used electric resistance heat for this water, but I kick myself as this is one of the poorest uses of 1 phase 240 VAC. Clearly, in the mid winter, like now, I get almost no hot water from the desuperheater and use resistance heating for hot water. I do have (and will have) propane so I could easily plumb in a tankless water unit in the rebuilt farm house, after the pre heat tank, to fire up if there is not enough hot water (turn off tank resistance elements). My thinking is that my ROI is probably best just using the existing tank. However, we have LOVED the efficiency and use of the Aquastar as it supplied gobs of endless hot water. When we had three young children, this tankless water heater was a wonder to behold. But it is hard to complain about essentially free hot water from the desuperheater for 1/2 of the year . . . Thoughts? Steve __________________ consulting on geothermal heating/cooling & rational energy use since 1990 Last edited by stevehull; 12-30-13 at 01:10 PM..