0 Helpful?

Best source for domestic hot water?

Getting ready to build a LEED certified home, tight construction, excellent quality windows. Ground Source Heat Pump based HVAC. Will use excess heat from heat pump for hot water, but need a storage/booster tank. HVAC contractor wants to use standard resistance tank heater. Is this sufficient? How do I best find a highly insulated tank? Essentially no one in my area of the country (Northeast Indiana) is building like this. Heat Pump tank? My HVAC contractor says that a demand heater would be too expensive/relatively useless as the water coming from the heat pump should be more than sufficient most of the year, and the tank is justly used as an insulated reservoir. I have "just enough knowledge to be dangerous not helpful". When we first sat down with our architect, he said that "...building green was a series of difficult compromises". This house is, in part, to be a demonstration of what can/should be done, yet we do need to be somewhat practical. Yet we are trying to keep electrical loads as low as possible.

Any suggestions?

Asked by Andrew Katz
Posted May 9, 2014 8:04 PM ET
Edited May 11, 2014 5:57 AM ET


3 Answers

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In your situation, a standard electric-resistance water heater is the appropriate tank. It provides storage as well as a backup source of heating. There is no need to invest in a heat-pump water heater, since you already have a heat pump.

Answered by Martin Holladay
Posted May 11, 2014 5:56 AM ET


Andrew , I concur with the caveat that this tank should be insulated well and be of good quality . Hard to find in the standard electric offerings of almost all manufacturers . There is one manufacturer that gets it however , HTP in East Freetown Mass has your heater , Look up the Everlast water heater . It has an EF of .91 , 2-3 inches of water blown foam insulation , 316 L SS tank , no anode rods needed for this reason , low wattage 3,000 or 4,000 elements and a lifetime warranty .
Within a budget and wanting to do the best you can this is the heater you want .

Answered by Richard McGrath
Posted May 11, 2014 9:32 PM ET


We use the Rheem Marathon, by far the lowest standby losses and available in the 105 gallon model I have to take advantage of my off-peak rates.

Answered by Morgan Audetat
Posted Jun 18, 2014 3:29 PM ET

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