8 Common HVAC Repairs

gloved hands repairing thermostat circuit board

Your HVAC system is a vital part of your home. When something is amiss with the system, you’ll want to get it back on track as soon as possible. Luckily, several common issues can be repaired somewhat easily in most situations.

1. Faulty Thermostat

Check out AC systems on Amazon.

While your thermostat may stop working or appear to be on the fritz, it might not be the actual HVAC unit but actually the thermostat. That’s great news because this usually means there's a pretty simple fix to the issue. Several potential issues with the thermostat could be that it’s not set correctly or the batteries need to be replaced. If you suspect a thermostat problem, try verifying the settings, resetting them as necessary, and replacing the battery. Check your HVAC system and thermostat’s manual to see any tell-tale signs that the thermostat is the issue at hand.

2. Dirty Filters

HVAC system filters should be replaced regularly to avoid a build-up of dust and debris, which could lead to this common problem. Pet hair and dander are something that contributes to a filthy filter. If you don’t replace yours as often as the manual dictates, the filter will eventually get dirty enough to block airflow the way it’s supposed to work. This can cause system errors or even for it to shut down completely and to overheat. If your system is having trouble, check the filter and replace it if it’s dirty to rectify the problem.

dirty filters on split air conditioner

3. Tripped Circuit Breaker

A tripped circuit breaker or blown fuse could be the source of HVAC issues. This is tricky, though, because an issue within your HVAC system could also prompt a tripped circuit or blown fuse. If you have a tripped breaker or blown fuse, first check if your air filter is dirty. Other likely causes are blocked air registers, duct leaks, or dirty coils. If you notice any of these issues as the culprit, first correct the issue before rectifying the circuit breaker.

4. Unusual Noises

Strange noises from your HVAC system can be alarming. While some sounds are part of the normal operation of your system, any whining or squealing could indicate that the bearings in the motor are failing. This means the motor may need to be replaced to avoid system failure. In other instances, strange noises could be prompted by airflow issues or dirty furnace burners.

5. Drainage Issues

Similar to issues with a clogged filter, AC drains can become clogged. Dirt, dust, and lint collect in the drain as time goes on and the system is used. This will cause the drain pan to fill up and water to leak out. This could cause damage to the AC unit or anything else around the pan. Empty the pan promptly and consider calling in a professional to assist in clearing the drain.

pvc pipes with built up water from hvac condensation

6. Compressor Problems

The compressor is a vital piece of the HVAC puzzle and acts as the heart of the system. If the system doesn’t have enough refrigerant liquid, the compressor will get hot and eventually quit. Liquid refrigerant will back into the compressor, causing liquid slugging. To fix this, consult your HVAC professional or the system’s manual to verify you’re using the right amount of refrigerant liquid. This is vital for the health and operation of the compressor.

7. Evaporator Coil Issues

The evaporator coil on your HVAC system may experience limited airflow due to blocked air filters or other issues, such as low refrigerant levels. If this occurs, the coil will freeze up. Whether your coil is outside or in your attic, it will need cleaning if this issue occurs. Plus, regardless of an issue, coils should be cleaned once every three years. If your coil is cracked, call an HVAC professional to assist in fixing or replacing it.

8. Blower Running Continuously

A few factors can cause a continuously running blower. To find the source of the problem and potentially solve it, start by checking the fan switch on the thermostat. If set to the fan position, that is the reason for the problem. Switch the fan to auto or off to resolve the issue.

An issue with your HVAC system may initially cause alarm, but many of these problems are common and have an easy fix.

When you purchase through links on our site, we may earn commissions at no cost to you.