Author Topic: Mistbox  (Read 2102 times)

dantownehall

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Mistbox
« on: July 20, 2015, 11:11:21 AM »
Has anyone out there tried out a Mistbox to save on AC costs?

It's a small device that evaporates a spray of water in the air around your AC unit so that the unit is sucking in cooler air and doesn't have to work as hard/run as much to cool the house.

It seems like a good idea, but was wondering if anyone had personal experience.

MDM

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Re: Mistbox
« Reply #1 on: July 20, 2015, 11:43:10 AM »
Not that exactly, but we have had problems in especially hot weather with blowing fuses due to a high power draw.  To fix that, we use a lawn sprinkler to spray into one side of the condenser unit.  No blown fuses when using the sprinkler.

James

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Re: Mistbox
« Reply #2 on: July 20, 2015, 11:49:02 AM »
I've thought about using a coiled soaker hose dripping water onto my condenser unit, but I am afraid it would mess up the unit and then I would be spending money to repair it... :)


I also figure if it really saved a lot everyone would be doing it, and they would sell after market drop hoses to use... but I am curious...

James

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Re: Mistbox
« Reply #3 on: July 20, 2015, 12:00:19 PM »

After reading a bit, sounds like it isn't a good idea. People talked about calcium and other deposits building up and harming the unit. Also, the compressor is what does most of the work, and that isn't benefited by the cooling effect of water. The coolant going into the house will be slightly colder if cooled by water, but not enough for any big savings. It is the change from liquid to gas that causes the cooling, not the overall temp of the coolant. There is also concern for rust and other issues due to constant moisture.

MDM

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Re: Mistbox
« Reply #4 on: July 20, 2015, 12:17:40 PM »
Also, the compressor is what does most of the work, and that isn't benefited by the cooling effect of water.

Actually there is a benefit.  The compressor has to increase the refrigerant pressure high enough for the condenser to condense the refrigerant.  The lower the condensing temperature, the lower the condensing pressure and thus the amount of work required from the compressor is that much lower.

The other considerations are valid and may (or may not) overwhelm this one, but there is a real savings to keeping the condenser cooler.

dantownehall

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Re: Mistbox
« Reply #5 on: July 21, 2015, 06:18:25 AM »
Also, the compressor is what does most of the work, and that isn't benefited by the cooling effect of water.

Actually there is a benefit.  The compressor has to increase the refrigerant pressure high enough for the condenser to condense the refrigerant.  The lower the condensing temperature, the lower the condensing pressure and thus the amount of work required from the compressor is that much lower.

The other considerations are valid and may (or may not) overwhelm this one, but there is a real savings to keeping the condenser cooler.

That's the impression I had from reading about it.  However, in my case I don't think it would be worth the cost/effort/potential damage to the AC unit - I don't use a lot of AC up here in the mountains.  If I still lived in Florida I might consider it more strongly.