Using small Window A/C for DHW Heater

[randen]

Xringer

Great project. I'm now old enough to remember how cutting edge and economic a combination oil/wood furnace was. I remember cutting splitting stacking drying stacking again wood for the furnace. It seemed to good to be true having the house so hot you would open the windows in a snow storm and wake up to a cold house having to build another fire. OOH the oil we saved.
Anyway The little down-side may be the constant air-flow generated by the chimney and in thru the oil burner and fire door. As you warm the water jacket the cooler basement air will flow in thru these things cooling your water and warming the chimney. Are you sure you want to place these beautifuly created highly efficient HPs onto a leaky old dinosaur instead of a nice well insulated electric hot water tank with one element removed on the bottom for the extra inlet you need for the HX. The top element you can leave for a little temp boost or even a dump for any extra solar power you may have. I think even a good used tank could be found. Just add one of those insulation kits from the Home Depot and presto another beautiful highly efficient envy of the eco-renovators ASHW tank.

Just saying
Randen

[AC_Hacker]

Originally Posted by randen

...presto another beautiful highly efficient envy of the eco-renovators ASHW tank.

Speaking of which, as I recall, you are doing solar + GSHP. Here is a paper on the subject by one of your countrymen.

-AC

[Xringer]

Just "another beautiful highly efficient envy of the eco-renovators ASHW tank"..

But, what if I can get by with ordinary/plain-looking medium efficiency envy?


I've been watching for someone changing out a hot water heater for a while,
but I think there aren't many DIYers doing waterheater installs these days..
Folks here hire installers and those guys make a few bucks doing disposal of the old tanks.

I have a buddy who does dump visits (got a 50" LCD HDTV last year)
maybe I'll ask him to watch out for a HW tank for me..

But, I'm getting ready to jump on this project and using the leaky old dinosaur.

Using the dinosaur does have some good points.
1. The HS Tarm is made of weldable Steel. (From Sweden), so it could last another 30 years (with a few repairs).
2. If the grid goes down for a few days (or months), we can still have hot water and heat. (using solid fuel).

Yeah, sucks air off the basement floor (containing Radon gas) and sends it up into the wild blue yonder.
But that creates a little ventilation in the basement.

I don't think it's really too lossy. In the morning (6:30AM) the burner runs for about 1/2 hour (@1gph) or until it hits 140F.
Right now, it's 12 hours later and it's dropped down to 138F.
There was some solar PV assist today(@2.4BTUh). Maybe 10k BTU was harvested. It was mostly sunny.

So, If I can run a 5,000 BTUh heatpump for a few hours a day @$0.1675 per kWh,
and avoid burning $2 of oil (maybe $5 or $10 by July), I would be a happy camper.

If I burn less than 12 kWh per day with the ASHP, it will be cheaper than oil.

[Xringer]

Originally Posted by AC_Hacker

Speaking of which, as I recall, you are doing solar + GSHP. Here is a paper on the subject by one of your countrymen.

-AC

That "natural convection heat exchanger" is pretty danged neat!
I'm wondering if I could just use a high & low tap off the back of my storage,
connected to my little HX.?.
Might be a good way to go, since a big pump would pull down the temp
of the HX pretty fast, if the storage water was too cool..
And natural convection would save complexity and kWhs..

[Daox]

Any updates on this project?

[Xringer]

I picked up 10' of copper tubing and some flare fitting the other day.
I'm getting to the point of picking out which AC I'm going to use for this project.

I'm going to have to figure out what to do with the charge (I assume it's R22).
I have three AC units that I need to get safely de-charged.
It would be nice to get them all done at once.

I've not yet decided if I really want to use propane for the hot water heater..

[charlesfl]

I priced r22 the other day. The price has doubled recently to $421 per 30 pound tank at the local hvac wholesale distributor.

Charlesfl

[Xringer]

Check out the price of the commercial version of my little project..

geyser Electric Heat Pump Water Heater | eBay




$1,414.59 and you get an older model Geyser..

[S-F]

I'm not sure I understand the point of these. If the evaporator is in the house you just have to pay more for heat any way. I suppose it's nice in the summer though. Am I missing something here?

[Xringer]

I kinda figured it would be a good thing to have in the summer too.
In the winter, our basement is already pretty dang cold (50s)..

But, for much of the year, it stays 60-72F down there.

I know a local guy who uses a Geyser water heater and he says it's fantastic.
But, I don't know if he's telling me everything about the other stuff in the basement.
The stuff that produces heat..

Anyways, he also uses inverter mini-split technology to keep his house warm,
so I'm pretty sure he's not running a big oil burner down there..


My original brainstorm for this project was to have dual evaporators & compressors.
One coil outdoors, and one in the basement. So, during the winter, when it was mild outdoors,
I could run the outdoor coil and not cool down my basement..
Then in the summer, I could run the indoor coil to get a nice dry basement..

Anyways, everyone kinda told me the idea was NG, so I decided to go with the standard setup.
If it won't work during the heating season, then at least I'll have cheap hot water part of the year..