8 Quick Furnace Fixes

Did you know that about a quarter of all service calls can be avoided with quick furnace fixes that cost little to nothing? If your furnace isn’t working as it should, check out these eight quick heating fixes before calling an HVAC technician. In this article, we’re going to focus on some of the most common furnace issues and solutions that can be taken care of at home!

Thermostat Isn’t Working

Many people assume they are having issues with their furnace when, in truth, the problem is with the thermostat. Here are several things to look into:

• The thermostat is set to “Heat” rather than “Cool.”
• What is the temperature setting? Perhaps it’s lower than you'd like it to be, which is why it’s not turning on as often.
• Compare the preset temperature to the room temperature. Try raising the temperature a few degrees and see whether the furnace turns on.
• Is your thermostat displaying the correct day and time? If it isn’t, this might explain why your furnace is not turning on when it should.
• Replace the battery. Your thermostat will not work if the batteries are dead!
• If your thermostat is visibly dirty, wipe off any debris or dust. You should also ensure that it is firmly attached to the wall and does not have any loose wires.
• Can’t get the program settings to work? You can put in the desired temperature using the up/down control, then push the hold button. This will turn on your furnace in the meantime, but you should also have an HVAC technician inspect your thermostat to avoid any problems down the line.

Examine the Shutoff Switches and Breakers

Believe it or not, HVAC technicians usually discover that the only “maintenance” furnaces require is to be switched on! Look for a standard wall switch on the furnace. If the wall switch is on, check the circuit breaker or fuse for the furnace. You should also make sure that the front panel covering the blower motor is firmly fastened—there’s a push-in switch beneath it that must be fully depressed for the furnace to work.

Dirty Furnace Filter

Is your furnace running but not producing hot air? This may be the result of a dirty and clogged furnace filter. Clogged furnace filters can restrict airflow and cause the heat exchanger to overheat and shut off. If you don’t change your filter often enough, your furnace’s lifespan could be significantly reduced! To prevent future problems with your furnace, we recommend that you change a flat filter at least once a month, and a pleated filter every three months. You may decide to replace your filters even more often if you have allergies, pets, or your home accumulates a lot of dust. Take a look at your furnace’s owner manual to see where the filter is located and how to change it. Before changing the filter, always be sure to turn off the thermostat and shutoff switch.

Gas Is Turned Off

This is another quick heating fix, and like your wall switch, someone may have turned off your gas valve and forgotten to turn it back on. Trace the gas line back from the furnace to the meter to locate the gas valve, and if you come across a handle that is perpendicular to the gas pipe, turn it parallel. If your furnace or boiler is older, remove the front cover and the burner cover to see whether the pilot light is lit.

Clogged Chimney Exhaust Flue

Occasionally, rodents and debris can fall into the chimney exhaust flue. Make sure to turn off the furnace and thermostat before dismantling the duct that exits the furnace, then you can check for debris. After clearing the debris, resemble the sections in the same order that you took them apart.

Dirty Drain Lines

Did you know that during the heating season, high-efficiency furnaces can drain several gallons of water every day? As a result, drain lines will become dirty over time. If they become moldy, the furnace will shut down. Fortunately, there is a quick heating fix! If your drain lines are dirty, you can clean them using a solution made of 25% bleach and 75% water. First, remove the hose, fill it with the bleach and water solution, then flush it out after a few minutes.

Blocked or Leaky Ducts

Are you getting heat in all but a few rooms in your house? Some of your registers could be closed, and simply need to be opened. Otherwise, the dampers or air conditioner bypasses may be closed (these are handles and can be found protruding from the ductwork). Another possibility is that there are leaks in your ductwork. Examine any ductwork you can access and if there are any noticeable gaps, use metal duct tape to seal them. You may want to call an HVAC technician to inspect your ductwork and ensure that you haven’t missed any gaps.

Blocked Heat Pump or Intake and Exhaust Vents

Unfortunately, intake and exhaust vents can become clogged, causing your furnace to malfunction. Check your intake and exhaust vents for debris and clear them if necessary. If ice is clogging one of your pipes, there is likely a bigger problem somewhere in your system. Remove the ice, then call an HVAC technician to determine what the problem is. If you have a heat pump, remove any leaves or grass that are on the fins of the outdoor compressor unit. We also advise you to hose it down to rinse off any dirt or debris before the heating season starts.