Furnace calls jump on the first cold night of the year, and many of them are for problems that sat there all summer: a clogged filter, a dirty flame sensor, a thermostat with dead batteries. Half an hour of checks in October can save you a cold morning in November.
Five things to check yourself
Change the filter. Pull it out and hold it up to a light. If you can't see light through it, replace it. Most 1-inch filters last one to three months, and thicker media filters last six to twelve.
Test the thermostat. Switch it to heat and set it a few degrees above room temperature. The furnace should start within a few minutes. If the screen is blank or dim, replace the batteries first.
Clear the space around the furnace. Keep about a metre clear on every side. Paint cans, laundry and storage boxes shouldn't sit next to a gas appliance.
Open the vents. Walk through the house and make sure every vent is open and not covered by furniture or rugs. On most systems, closing vents in unused rooms doesn't save money and makes the blower work harder.
Test your carbon monoxide alarms. Press the test button on each one, and replace any alarm past the date printed on the back. Most last seven to ten years.
If you have a high-efficiency furnace with plastic pipes running outside, check that both are clear of leaves and nests. Keep them clear of snow once winter starts.
What a fall tune-up covers
Some checks need a technician and the right tools. At a tune-up, we:
clean and test the flame sensor and igniter
inspect the burners and heat exchanger for cracks and rust
measure gas pressure and temperature rise
test the safety switches and the carbon monoxide level at the flue
check the blower motor and clean the blower wheel if it needs it
flush the condensate drain on high-efficiency models
You get a written note of what we found. If anything needs repair, you get the price before any work starts.
Signs you should book a visit now
Don't wait for the first cold snap if you notice any of these:
The furnace starts, runs for a few seconds, then shuts off.
You hear banging, squealing or rattling when it starts up.
Some rooms are noticeably colder than they were last winter.
The burner flame is yellow or flickering instead of a steady blue.
Your gas bill went up even though you're using the heat the same way.
If you smell gas
Leave the house first, then call your gas utility's emergency line from outside. Don't flip light switches or use your phone inside. We can help once the utility says it's safe.
Skip the reminder next year
The Homely House maintenance plan covers a fall furnace tune-up and a spring air conditioner tune-up for $18 a month. We call you to book both, you get priority booking if something breaks, and repairs cost 15% less. You can also book a visit for a one-off tune-up.