AC unit humming with no air coming out of vents
The system runs or hums while failing to blow any air through the vents. This leaves the space without cooling or airflow, rendering the HVAC system unusable until the airflow issue is resolved.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1checking thermostat settings and air filters
- 2turning off the AC and running the fan to thaw frozen coils
- 3contacting the installation company for warranty service
- 4Tried fixing it with dad
- 5Waiting for vents to spontaneously start working during the drive
In their words
Unedited, most upvoted first, each linked to the thread it came from.
“My central ac is pretty new (may) but it won’t pump out any air at all.”source ↗
“Whenever I turn my car on, there’s about a 33% chance the vents just don’t work, no air comes out.”source ↗
“And whenever I adjust the speed of the fan, I can hear something clicking like it wants to turn on, but it fails.”source ↗
“Another thing I noticed is that when the vents don’t work, there’s a 50% chance they’ll spontaneously start working about 20 minutes into my drive.”source ↗
“I can’t see the evaporator but we have no air blowing anywhere.”source ↗
“No air at all. When I have the power on the ac just hums”source ↗
Where this came up
People with this problem also raised
- 5Car heater blowing cold air even with good coolant and thermostat
- 3Why is my AC blowing warm air?
- 4Why is my aerator punching holes instead of pulling plugs?
- 3Refrigerator stops cooling properly after being moved on its side
- 2HVAC system stops taking refrigerant during charging
- 2Why is my new turbocharger screaming after a few hundred miles?