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Heating, Air Conditioning, Fridge, HVAC/Why is Apartment Warm When Cool Outside


QUESTION: What are possible causes of this problem? My fourth floor apartment in NYC stays consistently warm since late April. Beginning when I wake up, the apartment seems to want to get up to 82° regardless of the outdoor temperature. We've had some cooler days that have had highs in the sixties, but my apartment still stays between 80°-82°. When we have warmer days, 88°-90° outside, it won't get warmer than 84° inside. Even in the afternoon, which seems weird since all my windows face west (so you think it's getting much warmer in the afternoon than the morning). There are two, in-wall heating and A/C units and they do cool the place down, but I just think it's weird that it always seems to heat itself up to 82° even when it's cool outside, but never much warmer.  I can't get over thr possibility there's something I could do to keep it cooler without running the A/C so much.

ANSWER: Jonathan:

Did you just move in, or have you lived there a long time? If the latter, has it always been this way?

Is the apartment beneath you vacant (IE: AC turned off)?

Do you close the blinds/shades/curtains in the afternoon?


---------- FOLLOW-UP ----------

QUESTION: Thanks for the follow-up, Fred.

We moved in in January. At that time, it was obviously much colder outside, and the apartment was cold then (nothing the heater couldn't solve, but then, I also like it cold).

This is the first summer, so I don't have any history to go on.

I don't know for sure if the apartment below me is vacant, but I did do a walk-by after reading your response, and think I saw light on the other side. I could definitely find out for sure if it would solve the mystery.

I pretty much keep the curtains closed after noon, as I work at home and can't handle glare on the computer screens. The curtains are dark, but not very thick. I was thinking about getting heavier curtains, and that's what tipped me off to this mystery.

I'm going to add some extra detail now, and I'm just going to preface it by saying I understand I may sound like I'm paying way too much attention to this issue, but my mind can't resist a puzzle.

I thought adding heavier drapes behind the existing curtains might help keep heat out in the afternoon, and then realized I didn't have a record of temperature over time in my apartment, so I wouldn't really be able to say if the curtains were effective. I know, I know... I've just reached a point where I want to know what really works and how well. So, I bought an indoor temperature and humidity gauge (did some tests to see how accurate it was) and figured I'd watch it for a week or two to see how the temperature change before adding the drapes and those to the readings after I put the drapes up. That's when I noticed the living room / kitchen room combined area were oddly consistent in temperature from 10AM into the night. I thought it should be cooler than 82F at 10AM when it's in the mid to low seventies outside, and I certainly thought it would be warmer than 84F in the afternoon especially on hotter days, but nope. This place basically runs 82F-84F unless I run the AC. The AC gets it down to the correct temperature, but after I turn it off, it'll just rebound back to 82-84 within 30-60min. And, I've even confirmed that on days when I never run the AC during the day (out visiting clients, etc.) it never breaks that high. The gauge I bought had a history of the high/low temp from the last three days, and it says 82 and 77 as of right now, and I recall that being the case for the past two weeks of watching it, despite external temps being between 92 and 60. This thing sits almost in the middle of the space about 4 ft high on a counter that breaks up the kitchen from the living area. (P.S. I haven't monitored the bedroom and bathroom, which stay closed during the day)

Am I right to think this is weird?

Yes Jonathan.

Obviously, temperature will "creep" when the AC's turned off, but your experience is "temperature trot". :<)

There's excess heat from somewhere: Apartment below not AC'd, poor wall insulation, single pane windows, inleakage of outdoor air, a commercial kitchen hood exhaust duct in one of your walls, etc.

You didn't mention humidity readings, but if humidity runs above 55%, especially if it quickly rises above 55% after the AC cycles off, I'd recommend a "Blower Door Test" to check for infiltration of outdoor air. You might check for drafts around the windows.


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Fred Weldin


I can't help you if your whatsis won't work, people (Especially if it's a refrigerator); I have no experience with appliances, and I haven't been involved with H&AC service and repair since March 08, 1996 (Thank the Lord); I always send a "standard" reply to appliance questions and H&AC "Service and Repair" questions (about 20 a month), so if you want to know why your whatsis isn't working like it used to, ask someone else. A lot of my answers aren’t read by the questioners; in that event, I always send reminders to read the answers for a month or more (the word "idiots" comes to mind - actually there's another more appropriate word, but discretion prevents its use here). If you have questions about how big a unit you need, if one room's warmer than the others, if you want an opinion oas to scope of work on bids received, etc. just ask. Do visit, there's a lot of good information on sizing, ductwork, efficiency, as well as some techniques accomplished DIY-ers can use to troubleshoot and improve their H&AC. Finally, I want to thank all of the kind, serious people whom I meet here: I enjoy working with you. My wife says I'm "snarky" from time to time; as for you others, please use your imagination as to the responses swirling on the snarky side of my brain when I read your questions.


53 years in the business. See


B of ME U of D 1965, numerous classes, seminars and a lot of "Hands On" learning since.

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