Common Furnace Repairs
February 17, 2019
Common furnace repairs that may happen in the first 10 years
Not unlike any other home appliance, there are a few common repairs you may find yourself
needing to make to your furnace within the first 10 years of ownership.
The furnace capacitor is part of the fan motor in your furnace. It helps the fan motor start and
provides a steady flow of electricity to the motors.
If it fails, so will the rest of your system, which will be easily noticeable. Signs of a failing
capacitor are: loud humming noises, problems with your air conditioning running constantly,
blowing cold air and starting, or consistently rising electric bills.
If the furnace capacitor is starting to fail or becoming weak, it can be noticed and easily repaired
during recommended yearly maintenance.
Blowers run year round to keep air flowing through your household. Since the blower runs
year-round, they have potential to fail earlier than your entire system or other individual parts of
A regularly changed and proper air filter can help the furnace blower last a longer and run more
The blower catches all the dust and debris that can pass through your filter, therefore, if the filter
is not being changed regularly, it poses potential for the blower to fail prematurely due to
overheating from coping with an old, dirty filter.
Yearly service can also help a furnace blower last longer, because it is cleaned during
The vacuum switch, also called the pressure switch, is designed to shut your furnace down if it
senses negative pressure being created by the draft inducing motor. This protects your home
from backdrafting, which is exhaust fumes entering your system, then entering your space.
A damaged switch is a common cause for furnace malfunctions. Holes or tears, debris build up
or just old age of the switch can cause it so stop working.
Repairs and replacement of vacuum switches are common. The vacuum switch can start to fail
due to age, which can then result in faulty furnace firing.
If your vacuum switch needs replaced, it is most common to just replace the part itself, not your
A furnace ignitor is fairly self explanatory, it is what lights a burner and starts the combustion
process to turn fuel into heat.
Newer furnaces typically have an electric hot surface ignitor while electric furnaces typically
have a thin wire that receives an electric signal, gets extremely hot and will create a spark to
start the heating process.
Signs of a failing or broken ignitor are similar to a broken capacitor. Hearing your furnace turn
off and on, only feeling it blow cold or cool air and your furnace not running at all are signs that
your ignitor could be ready to replace.
Replacing your ignitor is another common occurrence around five to seven years of operation. It
can be caught during yearly maintenance and replaced.
These common repairs are no need to panic. With any home appliance, upkeep and repairs are
just part of ownership. With regular maintenance and knowing the signs of these common
repairs, your furnace can continue to function efficiently.