You will appreciate a functioning HVAC system when you come home one day to find that the system is not working. It may have been up and running before you left the house, but the air conditioner and the furnace no longer work, no matter what you try.

Once in a while, the system still malfunctions and fails when you need it, and knowing how to troubleshoot while waiting for professional assistance is crucial. This guide explains finding and solving the root cause of the HVAC problem. You will also learn preventive measures to keep the issue from occurring in the future. That way, you are not stranded, even while waiting for a qualified technician to arrive.

HVAC Problems: Troubleshooting and Solutions for Homeowners

Wherever you live, HVAC problems can occur without warning. If you live in a city like Sydney, with slightly hotter summers than other cities, Sydney aircon specialists can assist in fixing the problem. However, what if you can do most of the troubleshooting yourself, saving time and money? Take a look at the following issues and possible ways to fix them.

Clogged Air Filters: Clean or Replace Them

This filter purifies the air, ensuring it is clean enough to spread in the room. That means it becomes clogged with dirt, requiring cleaning or replacement occasionally. Turn off the system and open the front panel to locate the filter. If unsure, use online resources or the product manual to find the filter’s location.

Pull and inspect it; clean it under running water and leave it to air-dry if dirty. If it has been used for over three months, it might be time to replace it. Air filters usually cause issues because of their vital roles, so they should be the first things you check.

Faulty Thermostat: Adjust or Remove It

Another critical component of the HVAC system is the thermostat. It is the device that controls the cooling and heating in every home. Try turning it off and on before adjusting the temperature setting. Monitor the HVAC to see if there is an improvement or change. If the starting or running problem continues, turn off the thermostat and check the batteries.


Many thermostats run on batteries, although some work with electricity. Replace the batteries and try again; if there is no improvement, consider calibrating or replacing the thermostat. It is cheaper to do that than to replace the entire HVAC system.

Blocked Vents: Remove Dirt

If the thermostat is in good working condition, the next part to check is the vent. The vent slats can become extremely dirty due to a lack of maintenance. This is particularly applicable if the air conditioner or furnace is in a hard-to-reach area of the house. Over time, the vents may become clogged with dirt, preventing proper airflow or completely blocking the flow.

Turn off the furnace or air conditioner and check the vent. The air has to pass through the vent before reaching the filter, making it quickly clogged. Clean it with a soft microfiber cloth to remove the dust and debris. Using such a cloth ensures you do not leave lint behind, compounding the problem. Click here to learn how to clean vents on your HVAC.

Sometimes, the duct may be the problem, that is if the unit is a central system. If cleaning the vent does not work, the next step is to clean the duct thoroughly. However, this task is not for you; having a trained technician do it is ideal.

Ductwork is the piping that runs through the house to carry air from room to room. Sometimes, age or small animals may damage the duct, causing air to leak and interrupt the flow. A technician can easily find and fix this problem if that is the case.

Malfunctioning Outdoor Unit: Clean and Inspect It

It is rare for the outdoor unit to malfunction or stop working because it is designed to withstand the elements for long periods. The primary cause of a faulty outdoor unit is dirt; since it is outside, leaves and other forms of debris find their way into it, clogging it and restricting airflow.

The outdoor unit, called the condenser, removes hot air from the system. When the air conditioner runs, it helps circulate the refrigerant and release the hot air to replace by the cold air. When the furnace is on, the condenser releases cold air. However, when dirt clogs the condenser, the HVAC may stop working.


The solution is simple: clean the condenser to remove the debris. Use a garden hose set at low pressure to clean it further if necessary. If the condenser is the problem, cleaning and maintaining it should get the HVAC working again.

Preventing HVAC Problems and Maintaining Home Comfort

The following ways are ways to prevent HVAC problems in the future, ensuring you are comfortable in your home.

Replace the Filter Every Two Months

Be sure to check and replace it before the filter is clogged with dirt. Check it regularly and clean it if the filter is still usable. If not, replace the part to keep the system running.

Keep the Condenser Clean

Clean and maintain the outdoor unit as much as possible. You do not need to scrub the part every day or week; once every three months, remove the debris to improve the airflow and keep the unit running optimally. Also, keep the area around it clean to prevent dirt from easily clinging to it again.

Test the Thermostat

Ensure the thermostat is up and running at all times. It is not a part that easily stops working, so you do not have to worry about replacing it constantly. It may be as simple as changing the batteries once a year but keeping them in optimum shape for the best results.

Run Regular Maintenance Checks

Regular checks ensure the HVAC runs well, and you do not have to keep replacing parts. It also ensures there are no malfunctioning HVAC systems on your hands. If you can, contact the brand to find a qualified technician for maintenance.

Otherwise, contact other skilled HVAC technicians for further assistance. This resource explains more about maintaining HVAC systems.


Following the troubleshooting steps in this guide helps you maintain your system. Check the filter and clean or replace it. Ensure the thermostat works well and the condensing unit outside the house is in proper condition. Additionally, check the system monthly to keep it in the best condition. That way, you save time and money that would have gone to replacing the entire unit.