Cooling the air conditioner coils with water?
- Thread starter Allaned
- Start date
dnewton3
Staff member
It does reduce the temps and therefore help lower head pressure on the condensing unit.
But it's pricey to just run water on the coil continuously.
This is really an issue of being on the borderline of capacity for the heat load experienced. If it was a rare, incredibly hot day, and your system was struggling to keep up and needed that last little bit of temp delta to run and keep the house cool, I could see a temp use for this. But generally it's too wasteful to just run up the water bill. (And before someone says "I'm on well water" so there's no problem ... the concern is that well water often has a lot of inclusive minerals which will end up coating the coils with a film build-up over time).
If you end up having to do this frequently, then your condensing unit is undersized to begin with.
But it's pricey to just run water on the coil continuously.
This is really an issue of being on the borderline of capacity for the heat load experienced. If it was a rare, incredibly hot day, and your system was struggling to keep up and needed that last little bit of temp delta to run and keep the house cool, I could see a temp use for this. But generally it's too wasteful to just run up the water bill. (And before someone says "I'm on well water" so there's no problem ... the concern is that well water often has a lot of inclusive minerals which will end up coating the coils with a film build-up over time).
If you end up having to do this frequently, then your condensing unit is undersized to begin with.
I tried it on an old unit with just a capillary tube for an orifice. You could hear the compressor load reduce with the wetted coils. I didn't have an amp meter to check power. I'm sure efficiency went up because heat was being rejected to a lower hot side temperature, but if I remember correctly, the inside cold air temperature actually went up a few degrees. After thinking about it a little, I talked myself into believing that the lower high side pressure was pushing less freon into the evaporator and the gas leaving the condenser would have higher superheat which would reduce compressor mass flow some more. The system might have higher efficiency but lower capacity.
It was an interesting experiment but it didn't help cool the house any better and with the cost of water I don't think it would have saved any $ either. I just wash the coils out thoroughly at the start of the year and again just before peak heat weeks and trust the designers had the sharpest pencils for best performance. YMMV.
It was an interesting experiment but it didn't help cool the house any better and with the cost of water I don't think it would have saved any $ either. I just wash the coils out thoroughly at the start of the year and again just before peak heat weeks and trust the designers had the sharpest pencils for best performance. YMMV.
Just getting the coils clean will help I should think. What a swamp mess that would create.
I will have my wife stand outside with a hose sprayer, while I nap in the AC cooled house. I'll come out in a few hours to see how she is doing.
Supposed to be 88°F for three straight days. Yippee.
I will have my wife stand outside with a hose sprayer, while I nap in the AC cooled house. I'll come out in a few hours to see how she is doing.
Supposed to be 88°F for three straight days. Yippee.
Kestas
Staff member
I've done this before on hot, swealtery days. I'd park the hose nozzle next to the condenser with a slight water mist.
It does work.
Ive considered something like this along with some water misting on the roof. We have a dark brown / gray metal roof. It doesn't help things.
Ive considered something like this along with some water misting on the roof. We have a dark brown / gray metal roof. It doesn't help things.
I hope he is not paying sewer charges with that water because both water and sewer charges will far exceed the extra electricity to run that a/c in the hot temperatures. If the coil fins are clear and the fan motor is in good shape, his actions are not needed.
That used to be something they did in Phoenix in the late 70's. They used a fine mist that turned on when the AC turned on.
I have seen misters for sale to be used on AC units. Kind of like the misters you might see at Disney or an outdoor seating area at a restruant. I would be worried about scale build up over the long term.
I noticed this as well !
should be a very fine mist not a garden hose.
In this video a guy modifies a window ac unit us use water cooling of the condenser coil with a hose buried in the ground and small aquarium pump to circulate the water. The result was the efficiency rose by a factor of 2.5. Looks like it has potential.
4wd
$50 site donor 2026
My dad's house had central air that had a total loss water system. He had the option via valve line-up to dump it outside in the garden or down the laundry sink. System was from circa 1955.
As for the above picture, yes it will work, but a thin mist is all you need. My window unit is set up to splash condensate on things via fan movement. When I try to sleep it sounds like it's gargling, but, hey, it gets a point with the EPA for efficiency.
As for the above picture, yes it will work, but a thin mist is all you need. My window unit is set up to splash condensate on things via fan movement. When I try to sleep it sounds like it's gargling, but, hey, it gets a point with the EPA for efficiency.
I was about to mention this. Actually, I even remember as a teenager in the 1970s.
The window unit fan would splash up water from the condensate at the bottom of the unit onto the condenser coils.
Some days you could actually see the water running down the coils when looking at the outside of the unit
