Why is my apartment so hot when the thermostat is off?
Hot water continuously running through floor pipes to fan coil units radiates heat, pushing apartment temperatures to suffocating levels even when the thermostat is completely off. This inescapable warmth makes it impossible to sleep, forcing people to run separate floor AC units while their HVAC installers dismiss the issue.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
Why is my apartment so hot when the thermostat is off?
- 1Running a floor unit AC that vents out a bedroom window during the winterDid this help you?
- 2Turning on the AC temporarilyDid this help you?
- 3Opening multiple windowsDid this help you?
- 4Running fans on "on" and "circulate" modesDid this help you?
- 5Running dehumidifiersDid this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“My HVAC guy is gaslighting me and I’m suffering in it so I need something to change.”source ↗
“can I do anything to prevent the hot water running through pipes under the floor to my fan coil unit from heating up my apartment to an unbearable temperature?”source ↗
“When the building gets switched over to heat mode, my unit reaches 26 degrees Celsius. We don’t turn on the thermostat, and any attempts to cool the unit don’t work.”source ↗
“My current solution is to run a floor unit AC that vents in/out of the small window in our bedroom, so that we can cool the room enough to be able to sleep at night.”source ↗
“It‘s now November and ever since getting it installed my home is stuffy and feels suffocating/warm.”source ↗
“I have had my heat turned off all day because of this and it’s literally 68 in my home but 49 degrees outside.”source ↗
“Every time I come in from the outside it is like the heat is blasting on high all day even though it’s off.”source ↗
“My HVAC guy that installed the system isn’t helping at all.”source ↗
Where this came up
People with this problem also raised
- 2How to override a locked apartment thermostat
- 4Thermostat doesn't work after opening it up
- 2Why is my water heater getting hotter than the thermostat setting?
- 2New thermostat blowing hot air on cool setting
- 4Why is my thermostat stuck in heating mode with no cooling option?
- 3Why is my car overheating after changing the thermostat?