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What to Check First If Your Heater Isn’t Working

A chilly house is the last thing anyone would like to have in the dead of winter. A failing home heater is never a welcome development but sometimes no matter the efforts to keep the HVAC well-maintained, furnaces could still bog down.

You should consider learning more about why your furnace is blowing cold air .To stay calm amid the dilemma, homeowners should know how to deal with a malfunctioning heater. It is also good to know what steps to take to prevent such occurrences, moving forward. Before calling a technician, homeowners should check the following first:

Check the Furnace Power Switch and Safety Switch

Check the power switch. The first thing a homeowner has to do upon noticing that the heater is not turning on or not blowing hot air is to check the power switch. Sometimes power switches get accidentally turned off and so, it is worth checking. Sometimes when technicians go near the switch, or when the homeowner himself is carrying out some cleaning or home maintenance chores near the switch, the power on the button gets accidentally flicked. If the switch is turned on, but the furnace is not working then proceed to the next step.

Inspect The Fuse Box For Your Central Heater

Take a look at the breaker or fuse box. Sometimes the breaker panel is tripped, removing the power supply to the furnace. Double-check the breaker switch assigned to the heater and see if it is powered on. Sometimes, resetting is all it takes to get the furnace working again. However, if the breaker trips once again, there might be an underlying issue.   

If the breaker assigned to the heater keeps on tripping then is highly likely that a safety feature is activated hence it turns off on its own. If this is the case, it is best to get in touch with a certified HVAC technician who can inspect the heater and diagnose the exact issue. It is also likely that there is an existing electrical problem. If this is the matter then it is best to call a licensed residential electrician who can check on the power fixtures serving the heater.

Furnaces and home heating systems usually have built-in safety features that automatically cuts power into the system it detects an issue. Below are some examples of a home heater’s safety features that trigger a system turnoff:

Upper Limit Furnace Safety Switch

The upper limit switch, which is also sometimes called a furnace safety switch detects abnormally high temperatures. Once triggered, it automatically shuts off the system to prevent a fire. High temperatures within the system usually take place when the blower motor, the capacitor, or the control board suddenly fails. Get in touch with a licensed HVAC technician who can assess the problem right away, since the system also needs to be reset once this feature is triggered.

Vent Safety Switch

This switch gets activated when the flue gasses are not safely exhausted by the furnace. So once the flue gasses do not correctly go through the heat exchanger, the feature gets immediately activated and turns off the heater automatically.

One of the usual reasons why this safety feature gets activated is when the build-up of a bird’s nest or wasp nest blocks the vent. Sometimes, a chalky substance coming from the gas odorant can likewise block the heat exchanger and triggers the feature. Get in touch with a licensed heating technician who can accurately diagnose the matter and reset the system.

Flame sensor or thermocouple

Modern furnaces usually have a flame sensor, while older home heating systems come with a thermocouple. These features have the same function, and it is to detect a faint pilot switch. When triggered, it will shut off the heating system to prevent a possible explosion. Alternatively it may be that you need to reset your heating unit with the reset button, see how here.

Check the thermostat

Another thing to check before calling for professional HVAC repair is the thermostat. Sometimes, the thermostat is set incorrectly and so the furnace is unable to heat the whole house. For instance, it may not have been turned to “heat” mode, or it is possibly set at the “auto” mode at 72F. For both scenarios, the heater will not work as it needs to be set on heat mode. 

It is possible that a kid played with the thermostat settings, it was set incorrectly, or it may have run out of batteries. Given these, the homeowner should double-check and rule out the simplest reason why the furnace seems to not be working.

If using a SMART Thermostat, it is possible that the thermostat needs to be reset. Just remove it from the wall cradle and manually restart the thermostat.

Check and replace the air filters leading to the heater

Take a look at the furnace filter to see if it is filled with dirt and dust build-up. Clogged filters can harm the heating system as they unnecessarily strain the mechanism due to the restricted airflow. Also read our homeowners guide on location of furnace filters it is very informative. For instance, if the heater gets choked up due to a clogged filter, it may not have enough air in the system enough for it to cause overheating and a shutdown.

If the filter is clogged, or it has been three months since the last time the filter got replaced, the system needs a new one. Disposable filters need routine replacement every quarter. Replace the filter right away, and while at it ensures that the furnace door is closed after replacing the filter. When the furnace door is ajar, the heating system will not turn on as a precaution. Double-check on the door.

Sniff for weird odors

Smell the surrounding air next to the furnace. Does it smell like normal air inside your house, or is there a lingering burning odor? If there is a lingering burning odor, call a licensed HVAC technician right away. A Smoky or gas-like odor is a red flag sign that needs the urgent attention of a heating professional.

It is also possible that carbon monoxide is leaking from the system, however, if this is the matter, homeowners could not detect this on their own since this gas is odor-free. Given the dangers of carbon monoxide poisoning, it is crucial to have a reliable carbon monoxide detector that will alert everyone at home to seek fresh air and call for professional servicing.

Is your heater not working? We can keep you warm!

We at Reliable Standard Heating, Air, & Solar are fully committed to helping you with any of your heating and air conditioning needs. We have been providing a full range of home heating servicing for years, and our customers only have great feedback to tell. Get in touch with us whether it be due to a faulty motor, clogged vents, uneven heating, pilot light issues, routine maintenance, troubleshooting or upgrade. We will make sure your house will be warm and toasty in no time! Call us up through our hotline or schedule HVAC servicing through our online platform.      

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