Solve Simple HVAC Problems Yourself
HVAC Pre-Call Checklist
If your furnace or air conditioner has stopped running, there are a few items you can check before you call a professional. Here’s our HVAC troubleshooting checklist for homeowners.
What to Check Before Calling for HVAC Repair
HVAC problems are never convenient. Imagine a summer day at The Colony’s Hidden Cove Park, and when you get home, it’s 90 degrees inside. That’s a terrible way to end a day. Or maybe it’s winter, and after a day shopping at Grandscape, you find your heating system won’t turn on. That’s also a terrible way to end the day. The real question: do you try to put up with it, or do you call an HVAC technician for emergency service?
Don’t necessarily make that call right away. There may be some things you can check on your own before calling an expert. Doing so can give you more information to relay to us when you call. In some cases, you might even be able to resolve the issue on your own! For this reason, we’ve put together an HVAC pre-call checklist that you can complete before calling an HVAC technician.
Skip the Checklist and Call Immediately if You Notice These Issues
Before you do anything else, there are some instances where you should call a professional immediately. These situations can be hazardous, and poking around your equipment may put your home and health at risk. Here’s when to stop DIY HVAC troubleshooting:
- You smell something burning.
- You notice a rotten egg smell, which indicates a gas leak.
- The furnace pilot light is yellow or orange, which indicates a possible carbon monoxide leak.
- You hear loud electrical buzzing or humming.
- There are loud mechanical grinding noises.
- The unit or electrical cords are producing visible sparks.
- Water is pooling around the unit.
When your AC looks like Frisco Water Park or your furnace smells like rotten eggs, HVAC troubleshooting is unsafe. Call a professional immediately.
Why We Made This Checklist
When putting this HVAC troubleshooting checklist together, our goal was to make sure you’re fully informed about your equipment. That includes giving you information you can use to maintain your comfort on your own. If one of these steps solves the problem, you may be able to avoid an unnecessary appointment and the resulting costs. If it doesn’t, the information you gather can help our technician diagnose the issue faster.
Check Your Thermostat
The first item to check is your thermostat. It acts as the central control for your equipment, so if it’s not set correctly, it can prevent the whole system from running. Specifically, check these items:
- Check the Mode: Make sure the mode is set to the right position (either “cool” or “heat”).
- Check the Temperature: Set the temperature high or low enough to trigger the signal to your equipment.
- Make Sure There’s Power: If the screen is blank, try changing the batteries.
Inspect Your Air Filter
If the thermostat is working properly, try the air filter. Many HVAC issues we see in Frisco can actually be prevented by keeping the filter clean, so it’s an important area to check.
- Find the Air Filter: Your HVAC filter may be located in the interior equipment (found in either your attic or a utility closet) or behind a grille (usually in a hallway, but could be elsewhere in the house).
- Check for Dust: If the filter looks fairly clean, leave it. If it’s caked with dust, change it.
- Keep the Dirty Filter: A dirty filter could help our technicians with the diagnostic process. Store it in a plastic bag until we arrive.
Check Your Circuit Breaker
Your system’s power may simply be turned off. After all, if your AC breaker tripped, it will prevent the system from cycling on. There are multiple switches to check, so follow these steps:
- Find the Indoor Panel: It’s likely in a utility closet or hallway. Reset it, even if it looks like it’s on. Do so by turning the switch completely to the off position, then flipping it back.
- Wait Five Minutes: Many systems have a time-delay relay switch for safety, so it may take a few minutes for it to cycle on.
- Check Outdoor Switches: Air conditioners and heat pumps often have outdoor electrical panels. Check the outdoor disconnect near the condenser. Make sure it has not been switched off or pulled out. If you are unsure how your disconnect works, leave it be and call a technician.
Make Sure the Indoor Unit Has Power
Many Frisco HVAC systems have both indoor and outdoor units. You’ll want to make sure the indoor unit has power as well as the outside equipment.
- Find the Indoor Power Switch: Most air conditioners have an interior unit, so check on that. Often, the switch is mounted near the unit on a 2x4. It will look like a light switch, so someone could shut it off by accident.
- Check the Furnace’s Access Door: If you’re troubleshooting a furnace, check the access door. If it doesn’t shut tightly, it won’t activate the door switch, preventing the system from turning on.
- Check the Gas: For gas furnaces, make sure the gas valve is on and the pilot light is lit. The gas line is often outside near a meter. If the valve is in line with the pipe, it’s on. If the pilot light is off, you can relight it by following the instructions in the owner’s manual. Only relight it if you don’t smell gas.
Verify Airflow Isn’t Blocked
Only 27% of US homeowners clean the outdoor HVAC equipment regularly, but debris buildup is a common issue for both air conditioners and heating systems. That’s especially true in Frisco, where there are high levels of pollution and cottonwood fluff. Keeping proper airflow means removing blockages. Here’s what to check:
- Clean the Outdoor Condenser: The outdoor units for heat pumps and air conditioners are especially vulnerable to dirt and debris. Look for dirt, leaves, and cottonwood fluff on the AC condenser. Turn off power to the outdoor unit before cleaning it. With the power off, gently rinse loose dirt, leaves, and cottonwood fibers from the condenser coil with a garden hose. Do not use a pressure washer or open the cabinet. If there’s still material impacted in the condenser coil, it will need chemical cleaning from a professional.
- Clear Vents and Grilles: Make sure all return and supply vents are clear of dust, debris, and other obstructions. Also, make sure none of them are shut, since that can put excess pressure on the system.
- Check Exhaust Vents: For furnaces, check the exhaust vent on the exterior of your house. Clear out any debris, bird nests, dirt, and so forth.
When You Should Turn Your System Off
After these DIY HVAC troubleshooting steps, your system still may not operate properly. In these situations, the best course is usually to turn the system off and call a professional. Otherwise, the system is going to draw power without doing anything. Shut off your system at the thermostat if any of the following is the case:
- The interior blower is running, but the furnace/air conditioner itself is not.
- Indoor and outdoor units both run, but they only circulate room-temperature air.
- There’s little to no air from the vents, even though the heater/AC is running.
- The interior unit has ice buildup (keep the fan on to thaw it before the technician arrives).
- You hear loud metal-on-metal grinding or other loud noises.
- You smell something burning.
- The furnace pilot light is orange or yellow, a sign of a carbon monoxide leak.
- You smell gas.
What to Report During a “No Cool Call”
The climate in North Dallas can reach brutal highs in the summer, especially if your AC is not turning on. When temperatures reach over 100 °F with oppressive humidity, we treat “no cool” calls seriously. To best help you, we’ll need some specific information. Here’s what to report during an AC service call:
- Verify which Units Are Running: Check the outdoor and indoor units. The indoor unit should be blowing air through the vents at a steady volume. Note whether the outdoor unit is running normally, running continuously, turning on and off unusually quickly, or not starting at all. Runtime can change with the weather, thermostat settings, and equipment type.
- Check the Visible Wiring: Find the visible section of low-voltage wiring outside for damage. Do not touch it! Just report what you see.
- Report Whether You Changed the Filter: Note whether you’ve changed the filter recently.
Things to Note During a “No Heat Call”
Winters in Frisco and Plano tend to be fairly mild, but freezes can still happen. A “no heat” scenario is urgent when the temperatures drop. If your heat pump or furnace is not turning on, checking a few items can help our technicians get it fixed faster. Here’s a quick furnace service call checklist you can follow:
- Check for a Gas Smell: This is the first thing to make note of. If you smell rotten eggs or suspect a gas leak, leave the home immediately. From a safe location, contact 911 and your gas utility. Do not use switches, phones, or other electronics inside the home. Once the property has been declared safe, contact Colony if your furnace needs service.
- Check for Signs of Carbon Monoxide: If the furnace pilot light is yellow, orange, or constantly flickering and going out, you may have a carbon monoxide leak. Black residue around the burner is another possible sign of a leak. If you suspect a carbon monoxide leak, turn off your furnace, leave your home, and contact 911.
- Determine Whether the Heater and Blower Are Running: Check the furnace’s pilot light and the fan to see which is on. The furnace should cycle on and off at regular intervals. The fan should also be blowing. If either of those is out, make a note of it.
- Check the Heat Pump’s Outdoor Unit: If you have a heat pump, make a note of whether it’s running at regular intervals. Also determine if the interior fan is running.
- Report on the Filter: If you’ve changed your furnace’s filter recently, be sure to report that.
Things You Should Never Do During a Check
- Do not touch exposed wiring.
- Never scrape components clean with sharp tools.
- Avoid power washing outdoor equipment.
- Don’t add refrigerant yourself.
- Resist the urge to repeatedly reset the breaker, even if it keeps switching off.
- Do not prod tools into the equipment.
- Avoid attempting to disassemble the equipment.
- Never bypass safety mechanisms.
If the basic troubleshooting steps above don’t resolve your heating and cooling issue, don’t try to fix the issue on your own. Call a professional from Colony to take care of it.
Heating and Cooling Troubleshooting Helps HVAC Technicians
When you perform a bit of heating and cooling troubleshooting on your own, you can resolve some issues without having to schedule a service call. It’s helpful to know things like how to determine whether the furnace breaker tripped or how to clean an outdoor AC unit. This can help save you both time and money.
Of course, repairs are often still needed. In those situations, the information you gathered can help our technicians. With a little input from you, our NATE-certified technicians can isolate and repair the issue more quickly. We’re here to help when you can’t fix the issue yourself, so give us a call any time you need HVAC repair in Frisco, Plano, or Carrollton.
Frequently Asked Questions
What should I do if my thermostat screen is blank?
Try replacing the batteries. If that doesn’t work, you might have an issue at the breaker switch. Find the HVAC circuit breaker and reset it. If that still doesn't solve the problem, a safety switch might have activated. In Frisco’s humid weather, the float switch in the outdoor unit or air handler could have triggered, indicating a drainage problem. If that has happened, or if your thermostat just doesn’t work anymore, call a professional.
Where is the power switch for my furnace or air handler?
The power switch for interior HVAC units like furnaces and air handlers is usually mounted near the unit. Look for something that looks like a light switch mounted to a 2x4. That’s most likely the power switch for your unit.
Can a loose furnace panel stop the system from running?
Yes. Your furnace’s access door has a switch designed to keep the system from running if the door is ajar. If the panel is loose, the switch might not engage. Often, this happens as a result of people changing their own filters. If a furnace or blower isn’t running after a filter change, give us a call.
Should I tell the technician what troubleshooting steps I already tried?
Yes. That information can help us diagnose the issue faster. Specifically, it helps us know what has already been done with the equipment. Even if you accidentally made things worse, let us know since that can help us get a clearer idea of what’s going on with your system.
Can troubleshooting the system myself void the warranty?
Basic checks such as adjusting the thermostat or replacing a filter are generally homeowner tasks. Before doing anything beyond basic maintenance, check your equipment’s warranty and owner’s manual. Repairs, refrigerant work, electrical work, and bypassing safety controls should be left to a qualified technician.
When should I stop troubleshooting and call a professional?
Stop your HVAC troubleshooting if you notice any of the following:
- Burning or rotten egg smells
- Yellow or orange pilot flames (a sign of carbon monoxide)
- Loud noises while the equipment runs
- Visible sparks
- Pooling water
- Lack of heating and cooling while equipment is running
- Poor airflow while equipment is running
- Ice buildup
What HVAC problems should homeowners never try to repair themselves?
Anything that requires you to use tools to open the equipment should generally be left to professionals. That includes cleaning dirty condenser coils (other than gently rinsing), working with electrical components, handling leaks of any kind, or replacing heat exchangers and compressors. Attempting these repairs without the proper training can be dangerous and void your warranty.
What happens if none of the pre-call checks solve the problem?
At that point, call a trustworthy heating and cooling company to resolve the issue. Don’t try to fix HVAC issues on your own. Colony has an A+ rating with the Better Business Bureau, so you can count on us to fix your issue promptly and correctly.