Few things feel as frustrating as hearing your home’s air conditioner come on but not blow cool air. It’s likely that you’ll wonder if there is something you can do or if it’s time to call one of our HVAC technicians. Here is how to tell what you can do based on several common scenarios.
Clogged Air Filter
One of the simplest problems to check for is a clogged air filter. This is almost always a perfectly good DIY job. Locate your AC’s filters, remove them, and see if they are clogged. Things like dust, dander, and even pollen can clog an HVAC filter. If your home has a separate filtration unit or purifier, you will also need to check the filters on those components. If they look dirty, even without clogs, that could be a problem. Replace them, and see how well your AC performs afterward.
Issues With the Outdoor Unit
The condenser coils for a home AC unit are located outdoors. Ideally, the location reduces the risk that debris and dirt will clog the coils. However, condenser coils get fouled for lots of reasons. Particularly if the system hasn’t had routine maintenance in more than a year, the coils could be a problem.
If you see evidence of something like dead leaves or grass clippings clogging the coils, then try hosing them down lightly. However, fouling oftentimes is bad enough that it requires professional cleaning solutions. Our HVAC technicians can clean stubbornly clogged coils.
In extreme cases, the coils may end up icing over. This could be due to fouling. However, it could also be a sign that the condenser or another component is struggling. Low refrigerant levels can also cause the system not to exchange heat quickly enough to avoid icing.
Damaged or bent coils are never good. Especially if you see no signs of coil fouling, it’s a good idea to ask our company to send a technician over to take a look.
Thermostat Issues
It never hurts to check what the thermostat displays. If the thermostat is set to a low level but reports a higher temperature, it is a potential source of concern. The problem with that scenario is that the thermostat may not be properly communicating with the AC’s control unit. Wiring issues between the thermostat and the control unit are a job for our HVAC technicians.
You can try adjusting the thermostat to see if that has any effect. However, a large gap between the reported temperature and the set temperature is usually a sign that something else is wrong. The problem could be as simple as wiring or as complicated as a failed compressor or condenser.
Note that many thermostats use batteries. If a battery has failed, it can cause problems, including calibration drift. Replacing the batteries sometimes remedies the issue. You may need to change a few settings to get a response.
Low Refrigerant
AC systems are closed loops that suffer hardly any losses under normal circumstances. Some evaporative effects might be noticeable in old units, but these have usually aged to the point that it is time to replace them anyhow. The more likely culprit is a leak. A damaged refrigerant line, usually due to corrosion, could cause the AC to lose refrigerant. Also, some fittings can loosen and lose refrigerant.
Anything involving refrigerant is a job for our licensed AC repair technicians. Under no circumstances should an unlicensed person handle HVAC refrigerant. Proper disposal and replacement of refrigerant are crucial.
Homeowners can check a few things, however, to verify that a refrigerant leak might be the problem. Most modern refrigerants have lubricants in them to keep the AC’s parts in good shape. If there is a leak that you can find, you will likely see a small pool of oily fluid from the lubricant. Some refrigerant leaks also make hissing sounds. If you spot any of these issues, ask Burgess Plumbing Heating & Electrical Co Ltd to check out the problem.
Compressor Failure
A failed compressor can lead to some weird behavior. Particularly, the AC may run for a few minutes and then stop. Typically, this produces little to no cold air. Frequently, you will hear grinding or clanking noises. The circuit breaker may also trip.
Compressor failures should trigger a shutdown once the system recognizes that the compressor isn’t going to run properly. This often leads to short cycles that keep repeating.
In terms of DIY options, the only thing you can do is reset the breaker and try the AC again. If the problem persists, then it’s time to give us a call.
Capacitor Damage
Whole-house air conditioning systems use very large capacitors. These allow the AC to build up a strong charge for starting each cycle. If a capacitor has failed, the compressor or fan motor is unlikely to start. Some systems in this condition may hum and act like they’re trying to run without putting out cold air.
If you’re comfortable opening the system, you can look for a capacitor bulge. Make sure to cut all power to the AC before doing this. Air conditioners tend to have big capacitors, so a bulge should be obvious.
Capacitors aren’t user-serviceable components in a cooling system, so the best idea is to leave the power to the air conditioner off and call our company for assistance.
Vents and Dampers
The AC itself isn’t always the culprit. Vents and dampers control airflow from the AC to other locations. They also tend to close over time inadvertently. If you’re not feeling any airflow, check to verify that the vents are open. These are easily accessible because they’re right at the register. Dampers are often deeper in the ductwork and may require professional tools to access.
Failing Blower Motor
The blower motor pushes air from the AC into the ductwork. A failing blower motor isn’t user-serviceable, but you can tell whether the blower is the problem. When a blower motor fails, it usually does so with some noise and possibly a electrical burning smell. Grinding noises are common when components rub together. A blower motor that’s running out of lubricant may also give off a burning odor.
Rising Energy Bills
It is also worth checking your recent energy bills to see if your home’s electrical consumption has risen without a good reason, such as a recent heat wave. Compare last month’s bill to the same month from last year for a better idea. If you see a big increase, it could signal that at least one of the AC’s components has been failing.
Burgess Plumbing Heating & Electrical Co Ltd is a cooling services expert that has been in business since 1953. We have been a Lennox dealer for more than half a century and work on models from many other trusted manufacturers, too. Our company is a member of the Northern Regional Construction Association (NRCA) and CleanBC.
Many people in Williams Lake, BC who worry about failing AC units trust Burgess Plumbing Heating & Electrical Co Ltd to fix them, so let us know what we can do for you.
