How to Troubleshoot Common HVAC Issues

After nearly two and a half decades of service as an HVAC technician, I’ve been called to the scene of many HVAC issues that could have easily been handled by the homeowner had they known what to look for. While I would never recommend trying to fix a heating or cooling system when you might risk your personal health or property, ignoring an issue with the hope that it will disappear is equally reckless. I do recommend familiarizing yourself with the Common A/C Problems in Your Home.


Your wallet?and your technician, should you decide you need him or her?will thank you. And remember: Before engaging in any inspections or repairs, always make sure that you aren’t voiding warranties, damaging your property, or endangering yourself.These simple measures should be fine to perform without the aid of a professional, but whenever dealing with repairs, only attempt tasks in which you feel confident.

Start with What You Can See

When looking for the root of your temperature woes, start with what is visible and accessible. These are the easiest issues to address, and there’s no point in dismantling something that works best when left intact. The first question to ask: is air blowing out of the registers? ?Are they open? If they’re open and still not providing airflow, start by making sure that your thermostat, furnace, and air conditioner have power. ?If your battery-operated thermostat screen is blank, changing its batteries could be the solution to your problem.

Next, make sure that the circuit breaker hasn’t tripped. Both your furnace and air conditioner will have their own dedicated breakers. Find the breaker for whichever unit is causing issues. If you find that it’s on, turn it off for about 15 seconds, and then turn it on again. You will be able to see if this made a difference by checking your thermostat again, and the registers. If your electric thermostat is still on the fritz, it’s not too difficult or expensive to replace for the most part?don’t put it off!

Filthy Filters

If it isn’t an electrical issue, chances are you have an air filter that needs to be cleaned or replaced.The air filter associated with your ventilation system is easily accessible and needs more attention than most people remember to give it. A dirty filter would never completely block airflow, but stifled airflow with poor energy efficiency could indicate that your filter (or even a blockage further within the ductwork) is blocking a good deal of your air. If so, clean or replace the filter according to the appropriate instructions. If this still doesn’t fix the problem, you’re going to have to check the unit and ducts more closely.

Is Your Air Conditioner Running?

Ideally, your outside air conditioning unit should be resting on dry ground and blowing hot air. If not, you’re probably looking at issues that are relatively simple to have fixed. If there’s a suspicious puddle by your unit, it’s likely composed of condensation (meaning that your system is working harder than it can manage with your home’s humidity.) However, if there’s an oily surface around the unit, it might indicate a refrigerant leak. This leak needs to be repaired, as your unit depends on its liquid refrigerant in order to provide cool air. When it’s low, it causes your compressor to work much more than it’s accustomed to, which could lead to a more costly repair. Even worse, exposed refrigerant can pose a serious health and environmental risk.

If the fan isn’t blowing and transferring your home’s heat to the outside air, this can overheat your compressor, which will either trip the safety overload or cause internal damage.At this point, turn off the power to the unit and check the wiring for signs of damage. If it is behaving as it should yet you’re still lacking cool air, make sure nothing is obstructing the fan. The problem could also be your blower motor. Check its belt for cracks and breaks. The issue could also be a dirty coil, all of which can be remedied with the aid of a technician.

Getting Warmer

If the issue is with your furnace, it’s likely that the motor has been overloaded. Wait about thirty minutes and then find and press the reset button. If your pilot light is out, simply try to relight it. If it won’t stay lit, make sure the opening is clean and clear, and that you have gas coming to the unit. Also, make sure the flame isn’t set too low?it should hover around two inches.

If you’ve found that there’s no gas going to your unit, check to see if the gas valve to the furnace is completely open. If you’re still not receiving warm air from your registers, check the blower belt for breaks and cracks, or to see if it is too loose or too tight. Both of these issues can be adjusted at rates more reasonable than replacing your furnace entirely.

If your search fails to yield any results, consider how old your equipment has been running.If it has exceeded its typical lifespan, it could be time for replacement. If your system hasn’t aged too much yet still experiences trouble, you should call your technician. Communicate that you’ve checked all of these basic things, and he or she will more quickly determine how to fix your HVAC issues.

Special thanks to our guest blogger, Jason Wall. ?Jason is an HVAC technician with more than 23 years of experience who writes for Griffith Energy. When he isn’t working or writing, he can be found enjoying a good baseball game or spending time with his family.

If you would like more information or have questions about you HVAC system, you can visit us at ? for more information.