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Furnace Not Working?

Is your furnace not working? Try some of these tips before you call for a service technician

Winter season is coming and during cold months all homeowners will be relying on their furnace to heat their homes. But what if your furnace failed you and not heating your home? Furnace not working would be a big problem during the winter time for your indoor comfort.  If your furnace is not heating do not rush to call the service technician but try these few simple steps first and if they do not help then contact heating and cooling expert such as DeMark Home Ontario.

Check your thermostat

Check your thermostat settings before you assume your furnace not working. Sometimes homeowners forget to change the temperature settings or miss steps required for the furnace to start heating. Ensure your thermostat is set to heating mode. Also your thermostat may be broken or battery needs to be replaced on your thermostat, depending on the type of the thermostat you have. Check your thermostat first and see if this solves the issue of furnace not working.

Ensure your furnace is switched on

Some random occurrences can cause furnace to be turned off. There is an on/off switch located next to the furnace and it looks like a regular lighting switch. Someone in the household could’ve thought that it was a lighting switch and mistakenly turned it off.  This is a very easy fix simply turn the switch back on. If this was the cause of furnace not working it can save you from spending money on the furnace service professional to come and just turn the switch on.

Replace your filter

This is the most common cause of furnace not working. If your furnace is on and trying to heat your home but there is no air coming out form your ducts the it is the first sign of dust buildup which restricts the airflow. Replacing furnace filter every 2-3 months will solve the airflow problem.

Check ducts for debris and leaks

Air ducts can get clogged and decrease the ability of your furnace to function.  Also duct leaks are a common issue with heating systems. In some cases furnace works hard and increasing your energy bills and in some severe cases your furnace can stop heating your home properly.

Flush furnace drain line

All furnaces discard a few gallons of water through the drain lines every day. Backups, mold and other clogs can restrict the drain lines and cause furnace to stop working. Disconnect the drain line and flush it to get the furnace working again.


Is your furnace not working after you’ve tried all these tips?  Some furnace issues can only be determined by a heating and cooling professional.  Call DeMark Home Ontario for a repair service at  1 (855) 998-2998 or submit your request online.

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