What people keep running into with air conditioner
Complaints tagged air conditioner, each raised by more than one person. One-off posts are not included.
10 recurring problems · 128 people · 8 forums we read
Raised more than once
Most people first.
- 43How to clear a clogged AC condensate drain lineAlgae and slime buildup inside condensate lines blocks airflow and water drainage, causing the drain pan to overflow and leak into ceilings or floors. Clearing the blockage requires snaking or pumping out the standing water in the PVC lines and U-joints to stop the immediate flooding.
- 20AC making loud noise again after repairThe air conditioning unit is repeating a loud noise even after a recent repair, requiring the entire system to be switched off to stop it. This ongoing malfunction prevents the unit from operating normally and leaves the home without reliable cooling.
- 16What is this extra pipe dripping into my sink drain?The extra dripping pipe is an HVAC condensation drain line routed into your household plumbing. When it leaks or drips continuously, it usually points to a clog or blockage in the outflow line that prevents proper drainage.
- 13Why is my AC air handler wet and smelly?Old HVAC systems accumulate dust and organic growth that trap moisture inside the air handler, causing heavy condensation and persistent foul odors. Resolving this deep-seated contamination in aging units often requires replacing the plenum box or the entire system.
- 13Why do cooling coils keep freezing over?Melting iced-over coils with a heat gun fails to fix the problem because they quickly refreeze even worse within a day. This leaves the unit struggling to reach its temperature set point, trapping owners with a system that won't stay cold and leaving them unsure where to go from there.
- 9Why does my car A/C compressor keep turning on and off?An air conditioning compressor that repeatedly spins, catches, and stops causes low airflow for both cooling and heating. This short cycling prevents the system from maintaining stable pressures, leaving drivers frustrated by a lack of proper cabin climate control.
- 4How do I find out what size AC unit I have?Confusing equipment labels and a lack of documentation make it difficult to know what you are looking at or what size AC unit you actually have. Without clear specifications, people cannot figure out whether a 12k BTU capacity is enough or if an 18k unit is required for hot summer conditions.
- 4Cool air leaking from gap around AC copper pipe in atticAn unsealed gap where the copper refrigerant line enters an attic AC unit allows conditioned air to escape, creating a noticeable cool breeze in a hot space. Homeowners frequently discover this opening while changing filters and wonder whether it indicates a system malfunction or a harmless non-issue.
- 3Why is cold air blowing out of my AC drain line?Cold air blowing from the condensate vents happens when the air conditioner is running. While covering these lines stops the airflow, it causes the system's air pressure to create a thumping noise in the drain.
- 3How to cool down a house when the AC breaks during a heatwaveWhen an air conditioner breaks down during a heatwave, offices and maintenance services are often closed, leaving homes stuck at dangerously high temperatures. A dirty filter can cause the cooling coils to freeze up and stop the system entirely, leaving occupants scrambling for emergency DIY fixes to survive extreme heat.
Comes up alongside
Topics that keep appearing on the same problems — not topics with similar names.