When your ducted air conditioning system is blowing warm air, it can be difficult to work out the cause of the fault. The following four faults are some of the most common causes of ducted air conditioning system failure. Check for these errors to work out what problem is currently affecting your home air conditioning system.
1. Incorrect Settings
Before you do anything else, check that the settings for your ducted air conditioning system are correct. If you have the target temperature set too high, the system will blow warm air even if your home is very hot. Be sure to try changing the settings before you call an HVAC specialist. Read the manual for your ducted air conditioning system if you are not sure how the settings relate to how the system cools or heats your home.
2. Dirty Filter
One of the most common causes of a ducted air conditioning system not working correctly is dirt clogging the filter. Ducted air conditioners use a filter to get rid of common indoor air pollutants such as dust, hair and pollen. You need to clean this filter regularly to get rid of all the dust and dirt. Open the main air conditioning unit, remove the filter and use a small vacuum cleaner to gently suck away the dust.
3. Duct Leak
The air that is cooled by your air conditioning system travels around your house in ducts. If one of these ducts gets a leak, the cool air could leak out and warm air could be sucked in, resulting in warm air blowing from the vents.
Duct leaks are not always easy to detect. If your ducts pass through a space that you can easily access, you could try turning the air conditioning on and examining the ducts to see if you can find a source of cold air leaking out. Depending on how big the leak is, you might be able to patch it up with duct tape. If you cannot find the leak or don't know how to fix it, you need to contact an HVAC technician.
4. Faulty Thermostat
Sometimes, air conditioning systems blow warm air because the thermostat cannot correctly measure the temperature in your home. This can cause the system to default to recirculating air without cooling it. A skilled HVAC repair person can quickly identify a thermostat error and replace the faulty part with an inexpensive replacement.