# Air Tap Water Heater ??



## Helena (May 10, 2002)

Was watching a TV show the other day and they installed a...Air Tap Water Heater ??.. It takes the hot air out of the basement that is around your present hot water tank and it keeps the water warm in the take and takes less gas or electric to keep that tank water warm. Was thinking...we heat with wood and our cellar wood stove is on all winter keeping the cellar very, very warm. Has anyone had any experience or hear about these ????


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## Windy in Kansas (Jun 16, 2002)

Seems you are talking about the retrofit heat pump unit. Should work almost as well as a regular heat pump unit of which several manufacturers make. I find one retrofit unit sold only at $529.

A person could also get a retro unit and fit it to a stainless steel tank in order to make a nearly lifetime unit.

On the AirGenerate site under products I also notice the worlds first refillable sacrificial anode rod. Wish I could find a price on them. They seem like a great invention since the quality of the water here quickly eats away water heaters (salt). Expect that will somewhat change with the new reverse osmosis system now on line.

Glad to read about some innovative products. Thanks for the information even if I can't provide you with any usable information.


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## Windy in Kansas (Jun 16, 2002)

A good review here at Amazon: http://www.amazon.com/Airgenerate-A...953&creativeASIN=B001AMU09S&tag=spp-middle-20


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## Jim-mi (May 15, 2002)

And if you simply wrap your hot water tank with 6" of fibre glass insulation it will retain heat for a lot less bucks.

To me those skimpy hot water tank 'covers' are not worth it . . . .


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## 12vman (Feb 17, 2004)

I even thought about putting a stripped h/w tank next to the operating tank to take the chill out of the water before it enters the operating one. No need to plug that in to a wall socket.


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## Windy in Kansas (Jun 16, 2002)

Tempering tanks do work, and some do the water tempering with solar assist doing almost all of the heating.

The heat pump unit is much less costly to operate than conventional electric elements or a gas burner. That is where the savings come in. Specs were 12 amps starting and 6 amps running with 110volts. 660 watts is less than half of the consumption of an element unit. It would be interesting to use a Kill A Watt meter to see how many hours the unit actually runs per day and the KWH it consumes. Of course it would partially depend upon water usage and location temperature.

Since I don't use air-conditioning one thing I liked was that the expelled air from the unit can be ducted into living space, thus providing some cool, dehydrated air. 

Now if the developers would take this one step further and draw the heat from a refrigerator instead of the air from where the water heater is located----


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## SolarGary (Sep 8, 2005)

Hi,
Its a heat pump water heater.
It cuts the energy to heat hot water by a factor of about 2.
Most of them are relatively slow at heating water, so they have to be coupled with a water heater that has a regular heating element for when the heat pump can't keep up.

Other than the added complexity and cost, the only down side I see to them is that in the winter they cool the house air as they work. This is air that your furnace has to reheat back up to room temp. So, to some degree, this negates the energy saving for winter operation.

Some info here:
http://www.builditsolar.com/Projects/WaterHeating/water_heating.htm#HeatPumpWater Heater

The video by Tom Gocze is quite informative and funny as well.
The third link shows one way of partially overcoming the problem I mentioned above about winter operation.

I believe that some of these heat pump water heaters qualify for the 30% federal rebates, but others do not -- so if you want the rebate, be sure to check into this.

Gary


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## 12vman (Feb 17, 2004)

"Now if the developers would take this one step further and draw the heat from a refrigerator instead of the air from where the water heater is located----"

That's a great idea! I've even pondered having a small, insulated water tank above my propane fridge for a hot water source in the kitchen. Just big enough for a sink of dishes or something small. Mebby 5 gal. or so. Im most cases, the fridge is already in the kitchen.

But, on the other hand, I heat enough water with a pilot light to supply my needs and the flame in a propane fridge is about double the size..

Hey Gary.. Let's think about this.. HeHe.. Ya never know..


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## SolarGary (Sep 8, 2005)

12vman said:


> "Now if the developers would take this one step further and draw the heat from a refrigerator instead of the air from where the water heater is located----"
> 
> That's a great idea! I've even pondered having a small, insulated water tank above my propane fridge for a hot water source in the kitchen. Just big enough for a sink of dishes or something small. Mebby 5 gal. or so. Im most cases, the fridge is already in the kitchen.
> 
> ...



Hi 12V,
Interesting idea. 
The fridge is sort of a heat pump itself, but its pumping heat in the opposite direction to the heat pump water heater -- ie it heats the room its in instead of cooling it like a heat pump water heater does.

Since water heating is something you need year round, I don't see why a fridge that uses its waste heat to heat water would not be a good idea.

If the fridge uses (say) 2 KWH (6800 BTU) per day, and all of that went into heating water, you would get about 

gallons of water = (6800 BTU/day)/(50F)(1 BTU/lb-F) = 136 lbs (16 gallons) of water heated up from 50F to 100F every day.
I guess it might be more than than since its a heat pump and not just straight resistance heating.

I suppose that if you tried to heat the water too hot, that it would effect the performance of the fridge, since the condenser coil efficiency would drop as it gets warmer?

Gary


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## 12vman (Feb 17, 2004)

I was thinking of using the exhaust of the burner to heat with and leave the condensing coils alone. The only problem is the exhaust comes out of the top of the fridge through a chimney. That means the water tank would need to be above the fridge. 30-40 gal. of water is a lot of weight.. lol

Hey.. It's something to ponder on..


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