Temporary Advice

[brewyourown]

So I am in the process of lining up some HVAC contractors to assess my humidity situation along with my oversized furnace and AC.

in the meantime, what should i do on nights like tonight. It is 69 degrees outside right now with a RH of 87%. Inside it is 74 degrees with a RH of 59% with the AC on, but doesn't run very often due to virtually no heat load.
Temp is projected to drop to 61 tonight and I'm sure the RH outside will stay at least at 87% and possibly go a bit higher.

Should I open up the windows? Or leave the windows closed all night?

[RomulanSpy]

So I am in the process of lining up some HVAC contractors to assess my humidity situation along with my oversized furnace and AC.

in the meantime, what should i do on nights like tonight. It is 69 degrees outside right now with a RH of 87%. Inside it is 74 degrees with a RH of 59% with the AC on, but doesn't run very often due to virtually no heat load.
Temp is projected to drop to 61 tonight and I'm sure the RH outside will stay at least at 87% and possibly go a bit higher.

Should I open up the windows? Or leave the windows closed all night?

sells dehumidifiers.

[superd77]

The lower you set it , the lower the rh will be.

[beenthere]

The lower you set it , the lower the rh will be.
Not really.

He could end up with higher humidity by setting it too low.


Try leaving the windows closed. That will slow down the humidity infiltration.

[jrbenny]

Turn on the heat and crank it to 85. That'll get the relative humidity lower. :D

[gonekuku]

come on guys... he is looking for a practical temporary solution.

Build an addition to match the oversized system.

[Shophound]

When you go to bed, shut off the a/c completely and turn a fan on high speed, aimed toward the bed. You'll likely sleep soundly if you sense you're cool enough to drift off.

Since you say there's not much heat load to make the a/c run, you should probably be fine with the unit off and the windows closed overnight. If you begin to feel warm before hitting the sack, get under a fan.

[catmanacman]

@69 degrees outside i would open the window and put a fan in it

[brewyourown]

I ended up running a cheap portable dehumidifier that I had. It kept the humidity in the main portion of the house at about 50%. It was a very comfortable sleeping night even though the dehumidifier heated up the house 3 degrees from what it was when we went to bed.

I wouldn't want it as a perm solution though b/c it is loud and b/c it has to sit in the middle of a room and my house is small, so it takes up a lot of space, etc....

Out of the two HVAC contractors I called so far, the answering staff that is, one was knowledgeable about whole home humidifiers and said all the right things about sizing furnaces, etc... and the other seemed somewhat knowledgeable about sizing but when I asked about dehumidification, her answer was that the AC acted as the home dehumidifier.

We'll see what the actual sales guys/gals say when they see the house and I describe my issues in detail.

On a side note, I had found out that my electric company NYSEG has natural gas in my area and that since I am less than 100 feet from the line, they will install service to my house for free!!! And give me $500 toward a new furnace.

So, I now want to switch from my 84K BTU OIL fired furnace to a smaller more efficient natural gas furnace. According to some websites, natural gas right now is much cheaper than oil.

Is it true that natural gas furnaces come in more sizes and have more options for efficiency than oil furnaces?

[brewyourown]

Not really.

He could end up with higher humidity by setting it too low.


Try leaving the windows closed. That will slow down the humidity infiltration.

Just curious, in homes where humidity is NOT a problem, how is it that they can open windows on nights like last night where it got down to 61 degrees and not let all that humidity in? The RH this morning is 87%.

I would love to be able to just open windows, but when I do, the house gets up to 75% humidity.

[Shophound]

Just curious, in homes where humidity is NOT a problem, how is it that they can open windows on nights like last night where it got down to 61 degrees and not let all that humidity in? The RH this morning is 87%.

I would love to be able to just open windows, but when I do, the house gets up to 75% humidity.

You would need to define what in particular is meant by "homes where humidity is not a problem". If this means "the house is reasonably air tight when the windows and doors are closed and the a/c cycles sufficiently to control temperature and humidity", then if this particular homeowner shuts his a/c off at night and opens up the windows, his house will begin to load up with humidity, albeit more slowly than a house less airtight. Basic rule: greater levels of moisture seeks lesser levels of moisture. If the house absolute humidity is lower than outdoor absolute humidity, migration of moisture into the house will occur.

If you opt for a whole house dehumidifier, consider having a fresh air intake for it so the house air can be purged with dry air mixed with fresh air from outside.

[beenthere]

Some people don't mind letting the humidity get high in their house.
Many areas don't have as high of a humidity.

And yes, gas funaces come in more sizes then oil furnaces, and in higher efficiencies.