Crawl Space / Basement Dehumidifier Recommendation?
#1
08-10-15, 10:17 AM
Crawl Space / Basement Dehumidifier Recommendation?
Hello,
My mother's house has a 5' tall crawl space under the 1st floor, which has a retrofitted central AC system. This space is not easily accessible and is only frequented by service techs and myself when needed. I went down there to service the AC system and it is cool, but quite humid. The duct work for the AC has cold air is condensating the humid air, causing a lot of dripping water.
I'm thinking we should put a dehumidifier down there that can drain continuously into a sump pit. The unit should be turn on, set and forget, since we can't easily get to the controls for it.
Any options out there?
My mother's house has a 5' tall crawl space under the 1st floor, which has a retrofitted central AC system. This space is not easily accessible and is only frequented by service techs and myself when needed. I went down there to service the AC system and it is cool, but quite humid. The duct work for the AC has cold air is condensating the humid air, causing a lot of dripping water.
I'm thinking we should put a dehumidifier down there that can drain continuously into a sump pit. The unit should be turn on, set and forget, since we can't easily get to the controls for it.
Any options out there?
#2
08-10-15, 10:47 AM
Group Moderator
Any vapor barrier on the floor of the crawlspace?
Is this space open to or sealed from the outside air?
Is this space open to or sealed from the outside air?
#3
08-10-15, 11:09 AM
No vapor barrier. I believe it's just cement... and it's a 35 year old farm house.
I do not think it is sealed to outside air. I'm not even sure if that is feasible.
I do not think it is sealed to outside air. I'm not even sure if that is feasible.
#4
08-10-15, 11:11 AM
Group Moderator
OK, a concrete floor means you're not going to put plastic down there.
When I say sealed to the outside air, I mean there aren't vents open to the outside, right?
When I say sealed to the outside air, I mean there aren't vents open to the outside, right?
#5
08-10-15, 11:27 AM
There are some small 12"x8" openings to outside from the crawl space. I believe they have been sort of mostly closed off with wood to prevent cross wind from freezing the copper pipes, but I am not sure of any of the integrity. There's definitely no like crank, slide, or other windows... and I doubt any of them are air tight.
I might be back there later this week to replace the AC condenser unit fan and can get more info.
I might be back there later this week to replace the AC condenser unit fan and can get more info.
#6
08-10-15, 01:53 PM
Member
Without a vapor barrier on the ground you will just be spinning your wheels. But this is what id recommend.
Santa Fe - Compact2
Santa Fe - Compact2
#7
08-10-15, 03:13 PM
Ok mm, a 35 year old farm house, that's half my age so I'll call that new construction.
With a concrete floor down there it may or may not have a vapor battier under it, but in any case the concrete will at least slow the moisture moving into the air.
Your location or climate zone would help us determine the outside air humidity. If it is really humid outside it will be more so in that crawlspace.
You mention a sump pit, is it actively pumping out water? Are there any moisture issues down there other than the high humidity?
Where is the condensate from the ac unit draining. If to the sump pit that should be at least partially covered to prevent evaporation back into the air. Sometimes a pit can be loosely covered with a piece of rigid foam so in the event of a flood it floats out of the way.
Once you have addressed all of the known moisture sources then we can decide whether a dehumidifier or open vents is the best solution. If the current air quality is reasonable, just humid, that space could be insulated and added to the conditioned space where the ac unit would remove the humidity. Are ther concrete walls around the permiter?
Bud
With a concrete floor down there it may or may not have a vapor battier under it, but in any case the concrete will at least slow the moisture moving into the air.
Your location or climate zone would help us determine the outside air humidity. If it is really humid outside it will be more so in that crawlspace.
You mention a sump pit, is it actively pumping out water? Are there any moisture issues down there other than the high humidity?
Where is the condensate from the ac unit draining. If to the sump pit that should be at least partially covered to prevent evaporation back into the air. Sometimes a pit can be loosely covered with a piece of rigid foam so in the event of a flood it floats out of the way.
Once you have addressed all of the known moisture sources then we can decide whether a dehumidifier or open vents is the best solution. If the current air quality is reasonable, just humid, that space could be insulated and added to the conditioned space where the ac unit would remove the humidity. Are ther concrete walls around the permiter?
Bud
