Humidity and Temperature Issues in Apartment

[lawrence1111]

Hi guys,

This is my first post on this site, so I hope I am putting it in the correct section.
I recently moved into a studio apartment last week in the Virginia area, and since moving in, there's been a bit of a humidity issue that has recently gotten much worse. My apartment does not have central AC, just a wall unit in the main room, and no vents in that room. The humidity stays around 55-65% typically, which feels pretty muggy and was enough to peel the ceiling paint in my room, but was livable. I figured I'd just buy a dehumidifier if it really got too annoying. The AC kept the room around 70 degrees Fahrenheit, but there was a lot of condensation on the unit and the window all the time. I asked maintenance to see if there was a problem with the unit, but they refused to look into it. I have to keep the AC running 24/7 cold air or the humid shoots up above 65%.

Starting earlier today, my AC only blows out warm air now, and the humidity in the room has gotten to 80%. The temperature is 76 degrees Fahrenheit and rising. I can't even sit in the room anymore, as it is too uncomfortable. My clothes feel wet, my ceiling is peeling again (they just fixed it Thursday), and I just feel awful in the room, and I've never even had an allergy problem before. For reference, the outdoor temperature today is about 85 degrees, and the humidity is 50%. My room does feel worse than outside at this point. I'm also worried about mold.

Any ideas on what is now wrong with my AC unit? Is my apartment maintenance even responsible for fixing it? Thus far the only maintenance guy they have has not listened to me at all. Any advice would be appreciated.

[teddy bear]

Well as you know, your a/c is not working.
Who's a/c is it, yours or the landlords.
Someone either fixes it or get a new one.
Keep your space below the outdoor dew points is not a good idea because of moisture condensing on the surfaces expose to the outdoor air. 75^F is as cold as I would go. Get a/c working monitor the %RH. There things to do reduce moisture levels, including a dehumidifier. Do not let the mold grow or if you are sensitive you have to move out.

Keep us posted.
Regards Teddy Bear

[lawrence1111]

So the AC in my whole building apparently was not working, and it has been fixed. However, the humidity on my humidistat still reads between 65-70%. The apartment maintenance guy said that is a good humidity and that he can't do anything about it. However, I think that 65-70% is way too high for indoors? Whenever I wake up, I feel like I've caught a cold, but as I go about my day and leave my apartment, I feel a lot better. At what humidity should I be worried about mold? I've never had a mold issue before, so I'm not sure how sensitive I am to it.

I would try to keep the temperature at 75, but if my AC is not running constantly, then humidity goes up above 70%. So I have to run it all the time and keep it pretty cold in here so it feels more tolerable. I bought a dehumidifier, so maybe that will work.

What are the causes of really high humidity in an apartment? Does it have to do with my AC unit?

[teddy bear]

So the AC in my whole building apparently was not working, and it has been fixed. However, the humidity on my humidistat still reads between 65-70%. The apartment maintenance guy said that is a good humidity and that he can't do anything about it. However, I think that 65-70% is way too high for indoors? Whenever I wake up, I feel like I've caught a cold, but as I go about my day and leave my apartment, I feel a lot better. At what humidity should I be worried about mold? I've never had a mold issue before, so I'm not sure how sensitive I am to it.

I would try to keep the temperature at 75, but if my AC is not running constantly, then humidity goes up above 70%. So I have to run it all the time and keep it pretty cold in here so it feels more tolerable. I bought a dehumidifier, so maybe that will work.

What are the causes of really high humidity in an apartment? Does it have to do with my AC unit?

Sounds like you may have a central chiller. 50%RH is ideal but 60% RH is most recommend by ASHRAE. 70% would be my upper limit if the floor is not on the earth. On the earth like a slab on grade, <60%RH to avoid mold growth under a carpet on concrete on earth.
Adding a dehumidifier to space that the a/c is not keeping dry during high cooling loads is not always successful. Does you a/c have two speeds and a auto/on fan setting. Go with low speed fan when cooling and the "auto" setting.
Keep us posted on trying settings and the us of the dehumidifier.
Regards Teddy Bear

[lawrence1111]

So I got the dehumidifier last night and have had it running almost nonstop since then. Unfortunately, it only gets the room to about 55-65% humidity depending. I have it on full turbo mode, and set to 35% humidity, just to see if that would help, but it will not drop below 55%.

I realized that my issue may be insulation. The hallway outside my room is 80 degrees F, and 90% humidity, which I read with my humidistat. I have a doorstop on my side of the door, but standing over by the door, I can feel a flow of hot wet air coming in. My dehumidifier that's 30 pint removal per day capacity fills up nearly every 4 hours, which feels very fast. As soon as it fills up and shuts off, and I go to dump the water, the humidity increases by a few %. That's how much moist air is coming into my room constantly. I believe that the dehumidifier cannot keep up with the this influx of moist air from the hallway. Is there any way to effectively insulate against humidity?

[teddy bear]

Stopping air movement will help. Sealing the cracks in the door and other cracks will help.
What temperature are you keeping the room at? What is the air temp/%RH of the air coming from the a/c?
55%RH is a acceptable.
Keep us posted.
Regards Teddy Bear

[Andrew Agar]

As a part of the Florida contractors industry for some time, I have listened to this issue by the customers often, I would suggest to you the following reasons why this issue is occuring.
The reason is when the humidity level is high, the air conditioning system cannot work properly to reduce moisture in your room. Humidity affects your air conditioning cooling capabilities heavilly. Therefore, you may require a high functioning air conditioner as this is a natural issue. You can hire contractors for any hvac issue through

[michaelday]

The issue you are having is that moisture is entering from outside your apartment. The more you dehumidify and the lower you maintain your temperature the more moisture you will draw in. Sealing openings under doors or around windows will help. Unless your apartment building has a vapor barrier (plastic sheeting under the sheet rock) you can not stop the moisture from entering. The best thing to do is set your dehumidifier to the highest setting that is comfortable and will not encourage mold growth ~60%. Set your room A/C to the warmest that is comfortable ~75°F. Percent Relative Humidity is relative to the room temperature so higher room temperatures = lower relative humidity. You can purchase a small condensate pump to move the dehumidifier tank water to a drain so you won't need to empty it all of the time.