Follow our Easy Furnace Repair Guide

If it’s time for a new system, we also excel at furnace installation.

While we have you on the phone, consider a regular HVAC maintenance plan, which goes a long way to preventing problems in the future. It can also help make your system more efficient and may even make it last longer.

Follow the easy guide below to find out what problems your furnace could be having. Most of these steps won’t need anything other than basic mechanical skills.

1. Take a Look at Your Thermostat

Digital Thermostat

• Get new batteries if the screen is blank. If it’s scrambled, the thermostat may need to be replaced.
• Make sure the switch is in the correct setting.
• Also make sure the program is set to the right time and date settings, as well as set to “run.” To override the program, use the up and down arrows and press the “hold” button.” The furnace will start automatically regardless of the programming.
• Don’t forget to also try increasing the temperature setting to several degrees warmer than the room.

If the furnace hasn’t started in a few minutes, make sure it’s receiving power by switching the fan setting from “auto” to “on.” If it doesn’t start, the furnace may not be getting any power.

Smart Thermostat

A smart thermostat, like the ones by Nest, Ecobee, Lux, Honeywell or Bosch will have very specific troubleshooting options. Refer to the manual or manufacturer’s website for additional help. And if it’s still not working, call us at 469-200-3100 for all the heating and cooling service you could need, smart thermostats included.

2. Examine Breakers and Switches

Next, you’ll need to examine the breaker and furnace switches to see if they’re on.

• Locate the main electrical panel. Look for a gray metal box in your basement, garage or closet.
• Make sure hands and feet are dry before coming into contact with the panel or breaker.
• Look for the breaker labeled “furnace” or “heat” and make sure it is turned on. If a breaker has been tripped, it will instead be set to the middle “off” position.
• Try to switch the breaker back on. If the breaker trips again and turns off automatically, leave it alone and contact a professional at Diamond Blue Air at 469-200-3100. Our same-day service will get your heat up and running in no time at all.

No matter the age or brand, there will be at least one standard wall switch located on or near it. If it’s turned off, your furnace will take a few minutes to start up.

3. Replace the Air Filter

Many furnace problems are actually caused by clogged or dirty air filters. If the filter is too dirty:

• Your furnace won’t stay on, or could even overheat from the restricted airflow.
• Your energy efficiency won’t be as good since the furnace is turning on much more frequently than it should.
• The furnace could break down sooner because of this extra use.
• The furnace could also lose power if the filter causes the breaker to trip.

Depending on your furnace, the filter is inside the blower compartment, an attached case, or mounted to the return air grille.

If you need to replace the filter:

• Make sure the furnace is off.
• Remove the filter and hold it into the light. If you cannot see any light passing through, it’s time to throw it away and get a new filter.
• Put the new filter in the correct orientation (the arrow pointing toward the furnace) to avoid damage.

Flat filters are replaced once a month on average, while pleated filters last closer to 3 months. A washable filter can even last up to 10 years. Pets and children may require you to change your air filter more frequently.

To make it easier in the future, use a permanent marker on the housing or ductwork in your home to indicate airflow and filter size.

4. Inspect the Condensate Pan

These drain pans catch water your furnace takes out of the air.

If water is leaking, or the pan has standing water sitting inside, take the following steps:

• If the pan has a drain (look for PVC pipe), check that it is clear. If you need to drain it, use a special tablet available at home improvement or hardware stores.
• If the pan uses a pump instead, check the float switch. If the switch is stuck in the “up” position, with liquid sitting in the pan, contact Diamond Blue Air at 469-200-3100 because you probably need another pump.

5. Check for Furnace Error Codes

If malfunctions persist, take a look inside the plastic window of your furnace to view the motor. Depending on the model, the error code light could be mounted on the outside of the furnace instead.

If there’s anything but a steady, colored light or green, blinking light, call us at 469-200-3100 for service. The furnace’s error code might require professional help, and there’s no one better to handle the job. We back our work with a assurance*.

6. Clean the Flame Sensor

If your furnace starts for a while, but turns off without giving off any heat, a dirty flame sensor could be to blame. If this happens, the furnace will try to start three times before a safety setting will shut it down for an hour.

If you’re comfortable opening up your furnace and cleaning the flame sensor, here are the steps to take, or you can call us at 469-200-3100 to have a professional take a look:

Here are the supplies you’ll need to clean the sensor:

• A 1/4 “ hex screwdriver or wrench
• Light grit sandpaper, steel wool or emery cloth
• Dry, clean paper towels.

Once you have the correct supplies:

• Turn off the power via the wall switch or breaker. If the gas valve isn’t electric, you’ll need to shut off the gas as well.
• Remove the front panel of your furnace and follow the wires to the flame sensor.
• Unscrew the rod and use the abrasive wool or sandpaper to rub the metal rod.
• Wipe it down with a clean paper towel.
• Remount the sensor.
• Turn on the furnace after closing the doors. It may take several minutes to perform safety checks before the furnace returns to normal function. If it still doesn’t start, the sensor may be broken, or there’s another problem. If that’s the case, call us at 469-200-3100 and let the experts at Diamond Blue Air take a look.

7. Relight the Pilot Light

If your furnace is on the older side, the pilot light might be out. Relight it by finding the instructions on the furnace itself, or by following these simple steps:

• Find the pilot switch on the bottom of your furnace.
• Turn the switch to the “off” position.
• Wait no less than 5 minutes before relighting to avoid starting a potential fire.
• Turn the knob or switch to “pilot,” and then hold down the “reset” button as you bring the flame of a long lighter to the pilot light opening.
• Release the “reset” button once the pilot light has been relit.

If you have followed these instructions twice, and the light still will not come on, it may be time to contact Diamond Blue Air at 469-200-3100. Our friendly technicians are fully trained in both AC and furnace repair services. Our work is backed by a 100% assurance.*

8. Check Your Fuel Source

Try using another gas appliance. If that doesn’t work either, your gas or propane supply may not be working. Contact your utility company for help.

We Can Help with HVAC Repair

If you’ve followed our handy troubleshooting guide and the furnace still isn’t working, call us today at 469-200-3100. We’ll be out there as soon as possible, so you can get the heat pumping again fast.