house was at 70% humidity with ac cranked. we have dehu sitting in the house now a big santa-fe. what is the best way to duct it? i have read it is best to give it separate ducts or is it fine connecting to ac ducts? We have a seaparate one in crawlspace to keep mold away. This is in very humid SE.
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when we got in the house the temp was 72-75 inside and 90's outside very humid se summer. We were running a cheapo dehu just to do something and couldn't get it under 65 humididy even with house at 70 degrees outisde tem still very hot and humid. we have the santa fe on the kitchen counter right now lol because we just needed to knock this humidity out. within the day it was down to 49%. it barely runs. Only roblem is it is 49 in the living room next to dehu and 57-58 in the bedrooms. house is 73 degrees. this is a lot cooler than i usually keep a house trying to keep it at 55 or under. It was our plan to put it in the garage and duct as i thought that was what uit was for since it said it could be ducted. It's very big to keep in the house.
opp- funny they did mention our ac being large for the house size but said it shouldn't pose a problem for anything never said anything about humidity. of course these are the same hvac guys I'm having issues with so communication is not their thing lol.
thanks for the help
You might be better off replacing your AC with a smaller one.
Get a small window unit or two to set a baseline temperature in the house, run the fans continuous, as well as the dehumidifier. See if that helps. The AC is probably oversize or malfunctioning. Is the condensate running freely from the central AC?
As for the dehumidifier, if it's in the garage, it will be pulling hot humid air in and dehumidifying that air, but it will still be hot air and relatively humid. Not a good idea.
Even if it's ducted? I will have air handler insected to see what's going on. Oh we also have a searate dehu for crawlsaces so we don't have any mold problems again. I have been moving humidistat around the house so living room right next to dehu 49,back rooms 57 and last night I put in bathroom to see how high it goes with showers lol. Went into the 80's. Had the fun running for an hour after and door open. Now this afternoon it is still at 60 humidity and only 70 degrees so def. wouldn't turn on ac to make it colder right now. I've never worried about humidity levels in homes before but since we had the mold issue here I am trying my hardest to keep it under 55.
Proper use of a the bathroom fan is important for controlling humidity. The fan should run during a shower and for 10-20 minutes afterward. (A timer switch or humidistat switch is quite useful here.)
If inside air and return air is ducted to the dehumidifier, you should be ok, I'm not familiar how it works. If the two ducts are close together I think there will be a lot of recirculating air which would reduce the efficiency of the dehumidifier.
If the AC is oversize it won't run long enough to remove humidity. A small ac unit may need to run continuously to cool the house and it will be constantly removing humidity, so you will get lower indoor humidity.
If inside air and return air is ducted to the dehumidifier, you should be ok, I'm not familiar how it works. If the two ducts are close together I think there will be a lot of recirculating air which would reduce the efficiency of the dehumidifier.
If the AC is oversize it won't run long enough to remove humidity. A small ac unit may need to run continuously to cool the house and it will be constantly removing humidity, so you will get lower indoor humidity.
What you'd need to do, to put this in the garage, is build a LARGE cabinet/plenum around the intake side and pipe in air with LARGE ducts (significantly larger than the specified output ducts). If you restrict the incoming airflow the airflow will "stall" and the unit will ice up.
Maya,
You need a pro to do a Manual J on your system size and to check for leaking duct work that may be bringing in humid air from outside. You need to have a vapor barrier on the crawl space floor and walls. A dehumidifier is just curing the symptom not the problem.
KK
dehumidifier
Has anyone tried the WAVE ventilation system?
yes, since we just had ducts done, had issue with hvac that they are fixing and it has been almost a month we have had no insulation in garage and crawl waiting on them. house was very humid before any of this started but probably why it continues to be. this will be fixed in a week and their flex ducting taken out and relaced back with my lovely steel comletely sealed w/ mastic and wrapped w/ insulation. if we still have problems after that we will check size and if that is the problem might duct the two rooms that arent(sunroom and laundry) not sure why they arent ducted anyways as they are both of the living room and real rooms of the house. not going to worry about dehuing the house anymore:) thanks guys you aived me the 1700 on the dehu i'm returning. i am keeping the one for the crawlspace that def. needs it here in the summer.