Basic HVAC Troubleshooting Tips Every Homeowner Should Know

This blog post was submitted by Katelyn Brinn, Content Marketing Strategist for A-One Refrigeration & Heating, a family-owned and operated business that has been happily providing homes and businesses with quality HVAC services since 1980. When not writing, she does bird-watching with her family and relaxes through stand up paddle board yoga.

Your HVAC system works hard all-year-round to keep you cozy and comfortable through the change of seasons. Eventually, though, all that wear and tear will take its toll on the unit and cause it to act up or suddenly stop working.

Things can turn uncomfortable really quick when your AC system malfunctions. That being said, having a basic understanding of how to troubleshoot your HVAC unit will allow you to tackle most minor issues on your own and save yourself the cost of professional air conditioning repair.

Here are six common HVAC troubleshooting tips every homeowner should know:

1. No Power

Sometimes, it only takes a flip of a switch to get your HVAC working properly again. Is your unit completely dead or won’t turn or at all? It could be that your circuit breaker has tripped due to a power surge and cut off the power supply. If this is the case, you’ll only need to reset the system to get it up and running again. You’ll also want to check for any damage or fraying on the cord, as rodents or pests may have chewed on them and affected the power supply.

If none of the above issues seem to be the cause of the problem, check the outlet. Unplug the AC power cord and plug another high-voltage appliance into the port. If the appliance doesn’t work, the issue could be with the outlet; if it does, there could be something wrong with the unit itself – possibly a blown fuse or a faulty motor – that requires the attention of an HVAC professional.

2. Faulty Thermostat

Thermostats are generally reliable devices, but they can also malfunction or need maintenance from time to time. Plenty of HVAC problems originate from a broken thermostat. If your system isn’t starting properly or won’t turn on at, check if the thermostat has power.

Many thermostats are battery-powered. They tend to malfunction when the batteries run down and should work properly again after you change the batteries. If, however, a new set of batteries doesn’t solve the problem, you might need to call in a professional to recalibrate your thermostat and fix its on/off and temperature reading functions.

3. Weak Airflow

Another prevalent issue that affects both air conditioners and heaters is lack of sufficient airflow, which usually happens when the filters are clogged with dust and debris. Too much filth in the filters impedes airflow, preventing you from feeling either warm or cold air coming from the unit.

You should clean your air filters and replace them every two to three months. Doing so will not only resolve your airflow problems but improve the efficiency of your HVAC system and the air quality in your home.

Also, don’t forget to check the exterior unit of your HVAC system on a regular basis. Clear the surrounding area of clutter and remove fallen leaves, branches, and other debris can obstruct the unit’s airways or block the airflow.

4. Short Cycling

When airflow is restricted, your HVAC unit may also experience short cycling, causing the unit to shut down before it completes the heating or cooling cycle. Most of the time, this problem is easily resolved by cleaning or changing the air filter.

Another possible cause of short cycling is frozen coils. Check the evaporator coils, which are usually located in the air handler. If they have ice or frost on them, turn the unit off to let the coils thaw.

If it’s not any of the first two, a faulty thermostat that fails to get the right temperature reading could be to blame for the short cycling. This is often the case when the room doesn’t seem to reach your desired comfort levels. Because of the more complex nature of this particular problem, it’s recommended to leave the job to the experts.

5. Unpleasant Smells

Anytime you notice weird smells coming from your furnace or air conditioner, act on it as soon as possible because it could either be mold or burnt wiring; one just as dangerous as the other.

Molds are the likely culprit for foul HVAC odors, and they can pose serious health risks. In case of suspected mold growth, check for any leaks in your HVAC unit and make sure to seal them off. This will prevent the water leaking into your home and creating moisture, which is the ideal breeding room for molds.

If the stench comes from burnt wiring and electrical connections, call an electrician to help you deal with the problem immediately and avoid any hazardous situations.

6. Loud Noises

Is your air conditioner making loud noises? Then you should start your troubleshooting with the fan motor, which is responsible for blowing cool air into the ductwork and hot air out of the house.

Damaged fans can start making a lot of noise that’s very difficult to ignore. But even trapped dust and debris can make fans noisier than usual. If the latter is the issue, giving your unit a good cleaning might help reduce or get rid of the noise. The thing is; it’s not always easy to determine where the noises in your unit are coming from or what’s causing them. To ensure that correct repairs are made and further damage is avoided, ask an HVAC specialist to check and fix the unit.

When in Doubt, Call the Pros!

Most of these basic HVAC troubleshooting tips are easy enough to perform. But if you’re not sure what to do, you can always call your local HVAC company for help.

Looking for a contractor  in your service territory?

• BGE
• Pepco
• Potomac Edison

Also, consider scheduling at least two HVAC tune-ups every year – one before summer (for air conditioning) and the other one before winter (for heating). Professional HVAC maintenance will help ensure optimal performance and prevent your HVAC system from breaking down during the times you need it most.