Author Topic: Water Cooled AC  (Read 169 times)

Offline Hoofer

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Water Cooled AC
« on: June 22, 2017, 07:25:39 AM »
A carry over from the thread on Solar Panels.

What happened:   My AC went out at the house, the outside condenser cracked around the power leads, it's 18 years old, an R22 unit, good in it's day, I've patched it before on the Evaporator (coil in the furnace), but not having a good solution for this - time to retihink it.

The wish list:  Solar water pumping to cover the house and livestock (a farmette), for those frequent & untimely power outages.  And, a working Central AC again.

The immediate solution:  Replace the outside AC compressor and air condenser coil with an indoor compressor and water cooled condenser coil, plumb this into the well water.

The Ultimate idea:  I'd like to plumb this AC waste water into a preheater water tank, reverse flow, since I can pump out 110-130 degree water off the AC (not at a high rate, just slow & steady).   By *luck*, it's coming with a split heat exchanger coil, so I can take the hottest coil and run that through the preheater tank, and used the second coil to dump outside after the preheater tank is "hot"... which should be the only time I need to pump water from the well.   I'll need to work out the circulating pump for the domestic hot water, maybe a Grundfos with a temperature regulating valve so we don't turn the water over too fast through the AC coil... some tinkering involved.  The second half of the coil, *must* have a water regulating valve, it's open to the atmosphere, and basically gets "dumped" outside into the duck pond or a tank.  It can be over 100 degrees outside, and we can make the house as cold & dry as we want, without running up a huge electric bill.

Ok, how do we keep that big well pump from cycling every 5 min, even with an 86 gallon pressure tank, killing the deep well pump and spinning our electric meter like a top?   On the one hand, it's going to be electrically more efficient to cool the house with 50 degree water than 90+ degree air.   On the other hand, we have frequent power outages, meaning neither "we" nor the animals have water, if we don't have livestock tanks full, and bottles in the fridge ... not to mention, the inability to flush the toilets.  A bug plus, we have a fair bank of batteries for the outages, but cannot run the 230vac well pump without firing up the generator.

Hurricane season is also upon us - Irene left us 8 days without power.  It was up to the propane powered generator to keep us going, and it did OK, for a 1970s vintage unit. 

I really like the idea of solar panels running a small secondary pump for the AC and livestock.  When it's sunny, we need more AC, and the panels will run the pump.  When it's not sunny, we'll have to rely on whatever excess water we've pumped into a holding tank and/or the main well pump.

The Big Unknowns: 
1.  Is going with a 240vac inverter cheaper & more reliable than solar panels & a secondary pump?  (battery bank).
2.  Is a little solar powered pump really going to work for the AC *and* reduce the main well pump usage, ultimately lowering the electric bill for pumping and Central Air and domestic water heating?
3.  We get lightning strikes here - a single strike to the well takes out everything (because we'll have solar panels above it).
4.  Will 2 pumps work in the well, since I gotta pull the one, should I swap it out the 1/2hp with a 3/4hp and add the solar pump, or just install 2 solar pumps?
5.  How fast can my daughters drain all the hot water, and will this give them an excuse to take 3hr showers instead of 30min?


All animals are created equal; Some just take longer to cook.   Survival is keeping an eye on those around you...

Offline walkstall

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Re: Water Cooled AC
« Reply #1 on: June 22, 2017, 07:54:19 AM »
A carry over from the thread on Solar Panels.

5.  How fast can my daughters drain all the hot water, and will this give them an excuse to take 3hr showers instead of 30min?


Trust me.  I put in a 85gal hot water tank so I would have hot water for a shower.  My wife and two girl always used that water up.  The boy and I always had a cool water shower.  Until the girls move out.   :lol:  Good luck.
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Online Solar

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Re: Water Cooled AC
« Reply #2 on: June 22, 2017, 09:00:27 AM »
A carry over from the thread on Solar Panels.

What happened:   My AC went out at the house, the outside condenser cracked around the power leads, it's 18 years old, an R22 unit, good in it's day, I've patched it before on the Evaporator (coil in the furnace), but not having a good solution for this - time to retihink it.

The wish list:  Solar water pumping to cover the house and livestock (a farmette), for those frequent & untimely power outages.  And, a working Central AC again.

The immediate solution:  Replace the outside AC compressor and air condenser coil with an indoor compressor and water cooled condenser coil, plumb this into the well water.

The Ultimate idea:  I'd like to plumb this AC waste water into a preheater water tank, reverse flow, since I can pump out 110-130 degree water off the AC (not at a high rate, just slow & steady).   By *luck*, it's coming with a split heat exchanger coil, so I can take the hottest coil and run that through the preheater tank, and used the second coil to dump outside after the preheater tank is "hot"... which should be the only time I need to pump water from the well.   I'll need to work out the circulating pump for the domestic hot water, maybe a Grundfos with a temperature regulating valve so we don't turn the water over too fast through the AC coil... some tinkering involved.  The second half of the coil, *must* have a water regulating valve, it's open to the atmosphere, and basically gets "dumped" outside into the duck pond or a tank.  It can be over 100 degrees outside, and we can make the house as cold & dry as we want, without running up a huge electric bill.

Ok, how do we keep that big well pump from cycling every 5 min, even with an 86 gallon pressure tank, killing the deep well pump and spinning our electric meter like a top?   On the one hand, it's going to be electrically more efficient to cool the house with 50 degree water than 90+ degree air.   On the other hand, we have frequent power outages, meaning neither "we" nor the animals have water, if we don't have livestock tanks full, and bottles in the fridge ... not to mention, the inability to flush the toilets.  A bug plus, we have a fair bank of batteries for the outages, but cannot run the 230vac well pump without firing up the generator.

Hurricane season is also upon us - Irene left us 8 days without power.  It was up to the propane powered generator to keep us going, and it did OK, for a 1970s vintage unit. 

I really like the idea of solar panels running a small secondary pump for the AC and livestock.  When it's sunny, we need more AC, and the panels will run the pump.  When it's not sunny, we'll have to rely on whatever excess water we've pumped into a holding tank and/or the main well pump.

The Big Unknowns: 
1.  Is going with a 240vac inverter cheaper & more reliable than solar panels & a secondary pump?  (battery bank).
2.  Is a little solar powered pump really going to work for the AC *and* reduce the main well pump usage, ultimately lowering the electric bill for pumping and Central Air and domestic water heating?
3.  We get lightning strikes here - a single strike to the well takes out everything (because we'll have solar panels above it).
4.  Will 2 pumps work in the well, since I gotta pull the one, should I swap it out the 1/2hp with a 3/4hp and add the solar pump, or just install 2 solar pumps?
5.  How fast can my daughters drain all the hot water, and will this give them an excuse to take 3hr showers instead of 30min?
Definitely go tankless water heater, preferably one that doesn't require ACV.

But I'm confused when you say water cooled AC, are you referring to a heat pump, or a basic swamp cooler or hybrid cooling tower?
I have a swamp cooler, problem is, you may be cool, but you never get rid of the humidity that a compressor/condenser does, even a monster cooling tower where the water only passes over coils still leaves you with a humid situation  and the potential for mold to destroy your home, which is why I have a small 1200 BTU portable room air conditioner unit that keeps the humidity way down.
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Re: Water Cooled AC
« Reply #3 on: June 22, 2017, 03:49:24 PM »
This replaces the outside Compressor / Condenser unit.
http://www.ebay.com/itm/Water-Cooled-AW5532EK-Condensing-Unit-2-3-4-HP-High-Temp-R22-220V-1-Phase-/182297135471?hash=item2a71c1896f:g:93sAAOSw8w1X7WKo



Sits in the basement, you run cool water into it, out comes 120-130 degree water, temperature regulated by head pressure (you set what you want for pressure/tempurature).    They are very efficient AC units, the heat pulled out of the living space, can be partially used to heat domestic water.  I doesn't matter if it's 110 degrees outside, all it knows is the 50-60 degree water you're feeding it.

I built one from a 5000 btu old tank of wall-unit, an AC... years ago, it consumed less than 1qt of water a minute, and kept the apartment as cold as we wanted it to be, no matter how many people jammed into it for relief.  The apartment came with a 8600BTU wall-sleeve unit, (in the living room) which when the sun hit it, it did everything it could to keep it below 75 degrees with the curtains closed.   This old thing did the entire 2 bedroom apartment with a little fan in the hallway to pull/push the air back to the living room.

My father-in-law had one back in the 1980s, on his farmette, he didn't have enough of a cooling/heating load to heat his domestic water (in Wisconsin), but that house, was always comfortable, cool and dry.... and it was quiet, purring away in the basement.

Retrofitted a 21CuFT fridge/freezer with a tiny little 1/8hp, R12, 20vac "swing compressor", I think it drew 4-5amps (less than a 100watt bulb), and it worked fairly well too...but ran 100% of the time.   The compressor was just too small to circulate liquid/gas fast enough to pull the heat out for a deep freeze - a refrigerant volume issue.


I'd want a holding tank for the solar pump to fill, and a pressurized domestic hot water tank to give the AC something to preheat for us.   IF or when it reached 120-130, the head pressure would begin to rise, opening the water valve and dumping excess to the duck pond.   Or a sprinkler in the front yard for the kids to run through...  not really, you don't get much volume of water through these things.

NOTE:   Environmentalists would HATE these energy efficient things!!! :cursing: :cursing: :cursing: :cursing: :cursing:
"You're wasting water!  or.. electricity... or something!  You're NOT suppose to live comfortably while the rest of us are sweating like pigs on a spit."   :ttoung:
All animals are created equal; Some just take longer to cook.   Survival is keeping an eye on those around you...

Offline Hoofer

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Re: Water Cooled AC
« Reply #4 on: June 30, 2017, 05:09:42 PM »
Ordered 2 deep well pumps today, a 1HP for major use, running the house, livestock, etc., to replace a 1/2HP which can't run 2 showers.
Lucky for us, we're only 120-130' deep, with at a minimum 60' water column.

The second pump is a DC powered, 18-48VDC, rated 600watts... eventually to be mated with solar panels.  This one will pump water through the water cooled AC condenser.  Since I have a split coil, one part will serve as a water "pre-heater" the second coil will be fed from this "solar pump".  When the sun is out, it'll take the load off the main pump, we hope...!

Since we have 3 underground water lines, and probably one of them LEAKS, I found a normally CLOSED electric water valve, ball valve type.
That'll go on a timer, or to the solar panels, when it's dark outside, I want those multiple hydrants dry.  That'll keep the well from running as much.

What's really going on, our electric bill is in the $250-400 range in the summer months.   We're going to try and change that with a water cooled AC, pre-heater for hot water, and reflective foil in the attic.  For the last year, we've been logging data on the house / attic / outdoor air temps.  If this foil really does reflect heat, we'll have the evidence to show it, if not, we'll be able to show that too.

The final stage of revamping our energy usage, involves doubling the wall thickness and adding more insulation... maybe foil too.
We do not expect to eliminate electric bills, but rein them in considerably.  The whole house is running LED lights as of a month ago.

But this water cooled AC is quite an exciting project for us.
All animals are created equal; Some just take longer to cook.   Survival is keeping an eye on those around you...

 

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