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Safe to turn A/C off during summer?

  1. Sep 17, 2010 #1
    I have recently moved into a new home and off-gassing is really bothering me. I have developed contact dermatitis, and have even considered renting an apartment for a few months until this problem decreases some.

    Anyway, I know that heat increases the rate in which things off-gas. Is it safe to leave the A/C off in my home for a few weeks during the summer in GA - temps in the 90's.

    Worried about mold or other problems with humidity/heat.

    Thanks
     
  2. jcsd
  3. Sep 17, 2010 #2

    turbo

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    Can you rent a dehumidifier? That would help reduce the incidence of mold or mildew, and the waste heat from the unit would actually warm up your home a bit more. Off-gassing of new carpet and building materials would pose serious problems for me (MCS) so I understand your concerns. One problem with this partial solution is that airing out your home AND running a dehumidifier at the same time would overload that dehumidifier, so you'd need a constant-drain setup.

    As temperatures (and humidity) moderate, can you consider leaving windows open for extended periods? These days, chip-board, flooring materials and even gypsum-board have been implicated in sick-home problems. And it's not just FEMA trailers.
     
  4. Sep 17, 2010 #3

    Gokul43201

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    GA is going through a heatwave that is expected to last another week or so. After that, temps should drop to the 70s and lower.
     
  5. Sep 17, 2010 #4
    Why would the dehumidifier be overloaded? Is it required that I use a dehumidifier?

    Moderator Edit:Let's keep the discussion to this forum.
     
    Last edited by a moderator: Sep 17, 2010
  6. Sep 17, 2010 #5
    Here is the predicted weather - http://www.weather.com/weather/tenday/31545

    I wouldn't mind running my heater - that should dry the moisture in the air some, right?

    and my last post disappeared?

    I said would a dehumidifier be required? and what do you think about this thread
     
  7. Sep 17, 2010 #6

    turbo

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    I'm thinking that you would want to vent the off-gassed volatiles, and thus you would need some air-flow through the house (open windows or doors). The problem with that (open windows and doors) is that you would have a lot of airborne humidity to deal with, and the dehumidifier would be working overtime trying to cope with that.
     
  8. Sep 17, 2010 #7
    I own a chemical air filter - http://www.sylvane.com/airpura-v600-air-purifier.html

    I plan on running the air filter during the process. The filter does seem to help some, but I feel that I have developed a sensitivity, and would like to rapidly eliminate the problem if possible.
     
  9. Sep 17, 2010 #8

    turbo

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    Then your best approach, (IMO) is to raise the interior temperature of the building and keep it high, especially during the heat wave when volatiles in sheathing, siding, etc can be driven off most efficiently. Good luck!
     
  10. Sep 17, 2010 #9

    lisab

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    If you go this route, be sure to keep the humidity down. Mold loves hot and moist.
     
  11. Sep 17, 2010 #10

    turbo

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    Yep!
     
  12. Sep 17, 2010 #11
    I would assume that running the heat would dry the moisture out of the air until the house heated above the max thermostat setting of 90F. After that point, I don't think the humidity level would raise enough before the house cooled again to 90F and the unit starting heating the home again. What do you think?
     
  13. Sep 17, 2010 #12

    lisab

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    Well, we have at least one HVAC engineer here (Russ :wink: where are you), but here's what I think would happen.

    Raising the temperature doesn't remove much moisture from the air, but it does increase the air's capacity to hold moisture. This decreases the relative humidity, but the amount of grams of water per cubic meter stays the same.

    The problem is, if you're in a humid area the incoming air might already be warm and full of moisture. So warming it further could really set off mold growth.
     
  14. Sep 17, 2010 #13
    Well in my flat in London (by no means hot even in summer), we only had mould problems in the damp cold conditions during winter. Over the summer, when it was warm we didn't have any mould. Then again, the air is fairly dry here in the summer compared to the winter so that could also help prevent it.

    During the winter, if we didn't turn the heating on for prolonged periods to raise the internal flat temperature above 20 degrees and help keep the dampness away. The mould would only form in the cold damp conditions, not the warmth. The flat was definitely dryer when warm. Condensation would form internally in the cold and mould would spring up where it was if we didn't get the heating on damn quick.
     
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