When your furnace unexpectedly stops working during the harsh winter months, the situation can rapidly become unpleasant and uncomfortable. And you don’t want this, do you? If you are wondering why furnaces stop working in cold weather, there are plenty of reasons they can fail. Some of these reasons, as given by furnace repair service providers, include:

Interrupted power supply

All modern furnaces include a safety device known as a limit switch, which should automatically shut off the heating system if any problem overloads its electrical circuit and cause the breaker to trip. The first thing you should do if your furnace won’t turn on is to verify that the breaker hasn’t tripped.

Even gas furnaces require electricity to power the control board, inducer fan, and electronic igniter, as well as the blower, which circulates air throughout the system.

This means that your heating system will not operate if electricity is not flowing due to a tripped breaker or any other wiring or electrical issue.

If the breaker is tripped, reset it and see if your furnace starts. If the breaker immediately trips again when your heating system tries to start, it means there is an electrical problem that is overloading the circuit. You should have it checked out by a professional.

Faulty inducer motor

When your furnace comes on, the draft inducer starts about 30 seconds before the furnace illuminates. Burning gas emits carbon monoxide and other hot combustion gases.

The draft inducer draws these vapors from the combustion chamber through the heat exchanger and finally out of the building via the exhaust flue. This is critical for both safety and ensuring the furnace functions correctly.

If these combustion gases linger in the combustion chamber, they would deprive the burners of oxygen. As a result, the gas from the burners would not fully combust, leading the furnace to produce significantly less heat.

This is why the draft inducer runs before the furnace is turned on, to guarantee that no fumes stay inside the unit. The inducer creates negative air pressure inside the stove, triggering the unit’s pressure switch.

The pressure switch then sends the gas valve to open, allowing the furnace to light. If the inducer motor is worn or malfunctions, the pressure switch will not activate, and the stove will not ignite.

Just as you should have a complex electrical problem checked by a professional, you should have your inducer motor checked by a professional.

Broken or dirty flame sensor

If your furnace has an electronic igniter, it also includes a flame sensor that detects when the burners are lit. If the flame sensor is unclean or faulty, it will be unable to identify when the furnace is lit.

If the flame sensor does not detect and activate within a few seconds, the gas valve will close, and the furnace will turn off instantly. This is one of the most prevalent furnace problems, yet one of the simplest to avoid.

All it takes is having your furnace professionally repaired every year, and the expert will clean and test the flame sensor to verify it functions properly.

No gas flow

Your furnace will also be unable to light if gas is not supplied to it. If you have any other gas-burning appliances, check whether they are still operational, as the gas supply to your home may be cut off for some reason. You should also ensure that your furnace’s primary gas shut-off valve is completely open.

If gas is flowing to your other appliances but not your furnace, it is most likely because the gas valve has broken and become stuck shut. Fortunately, repairing a damaged or malfunctioning gas valve is relatively affordable and straightforward.

Malfunctioning pilot light

Unless your furnace was installed before 2010, it most likely has an electrical igniter rather than the classic pilot light used on earlier models. In either case, if the electronic igniter fails or the pilot light goes out, your furnace will not start.

Both an electronic igniter and a pilot light can fail due to regular wear and tear or other faults and may require replacement.

If you have a pilot light, the first thing to do is make sure it is still lit. If the pilot light does not ignite or stays out, it is most likely due to a problem with the thermocouple, pilot gas tube, or pilot control.

Faulty pressure switch

Even when the inducer fan is operating correctly, the pressure switch may occasionally fail to activate. The switch contains a small suction tube that monitors pressure and activates it; however, this tube can occasionally break or come free.

The pressure switch itself may potentially fail or become trapped in the closed position. In either case, the remedy is to repair or replace the pressure switch.

What should you do when the furnace stops working in winter?

There are several things you can do when your furnace stops working. Some of these things include:

Check the common issues

The common issues are the ones we have detailed above. If your furnace is not working or has suddenly stopped working, you should look into the problems mentioned and try to troubleshoot your unit.

Some of the things you should do include:

Make sure the thermostat is set to “heat,” and the temperature is above the current room temperature.

Inspect your furnace’s power connection. Here you should check that the circuit breaker has not tripped or a fuse has not blown.

For gas furnaces, make sure the gas valve is open.

Dirty or clogged filters may cause your furnace to shut down. Replace the filter as necessary.

Engage the services of a professional

If you are unable to repair the furnace yourself, it is essential to contact a professional furnace service Port Jefferson technician. A licensed professional will swiftly diagnose and address common problems such as:

• Faulty ignition systems.
• Filters that are clogged.
• Malfunctioning thermostats
• Damaged blower motors or heat exchangers.

If your home’s temperature is dangerously low, hire a professional as soon as possible. You don’t want to be stuck in a cold house in winter, do you?