Furnace Not Turning On: Top 5 Things To Consider When Furnace Not Turning On

furnace not turning on

Breakdowns in Grand Rapids area furnaces can be one of the most frustrating winter seasons. Several reasons why a furnace fails; some can be fixed quickly through troubleshooting, and some require professional repair. 

There can be complicated or straightforward reasons why your gas furnace isn’t working. The complex problems involving thermocouples, wiring, heat exchangers, and blower motors are probably better left to an HVAC contractor. However, there are a few things you can check yourself before reaching out to an HVAC contractor for furnace repair. You may notice when the furnace is not turning on for several reasons. Here is a list of the most common ones and how to deal with them.

5 Things to Consider when furnace not turning on.

Thermostat set incorrectly         

To start, check if your thermostat is functioning correctly or set up correctly. When indoor temperatures drop too low, the thermostat initiates your furnace’s operation, signaling it to turn on when the air becomes too cold and shutting it down once it reaches an appropriate temperature. Your thermostat won’t communicate with your furnace correctly if it is not set correctly, resulting in furnace problems, such as the furnace not turning on when it should.

Modern computerized thermostats frequently show an error signal when something goes wrong. See if the display indicates what the issue is by checking it. After attempting each solution, if the problem persists, it is probably a little more complicated than a straightforward thermostat fix. To discover some potential additional causes, keep reading. Check the thermostat to ensure that it is set to HEAT. It should be set to a higher temperature than the current room temperature.

Power outage

A working furnace requires power for all components of the heating system. As long as you don’t have a power outage affecting your home, ensure you’re powering each system component with individual switches and power sources.

  • It is possible that the thermostat’s batteries are dead if it displays no information or can’t be adjusted. It would help if you replaced them. Check the circuit breaker that controls the thermostat if it is hard-wired. Upon resetting the breaker, the power will be restored to the thermostat.
  • Verify that the circuit breakers supplying electricity to the furnace are functioning correctly. Reset the circuit breakers if they have tripped.
  • Be sure to check the on/off switch on or near your furnace, and make sure it is set to ON.
  • When using a natural gas furnace, make sure the gas valve is open so that fuel can enter the system. 
  • You should check your fuel tank for an oil or liquid propane furnace to ensure enough fuel to operate the heating system. Keep the fuel level above four inches; order a tank refill before the level drops below 25 percent for liquid propane tanks.

The pilot light is out.

Several older furnaces still use pilot lights, even though modern furnaces use electronic ignition. A draft or system problem will cause the pilot light to go out, which results in the furnace being unable to produce heat.

  • It is usually located near the bottom of the furnace, so look there for the pilot light assembly. If your furnace flame does not burn, you might need to replace the pilot assembly.
  • It is necessary to relight the pilot light if it is out. To begin with, stop any drafts that could have caused the pilot to extinguish. Allow at least five minutes for any gas to dissipate before turning off the pilot switch. 
  • When the time is right, relight the pilot according to the instructions in the owner’s manual of your furnace. 
  • Watch the pilot flame to ensure that a solid blue flame doesn’t extinguish again after it is relit. There may be an issue with a thermocouple if it goes out. Dirt or other debris may be clogging the air intake if the flame is weak and yellow. Get in touch with your HVAC service technician for an assessment and repair.

Air Filter that’s dirty

Dirty filters can restrict airflow, causing heating systems to overheat. It will be apparent that your furnace won’t turn on if this occurs – the system’s safety controls will shut it down so that it can cool.

Read more:Air Conditioner Cost: Each And Everything You Need To Know About Air Conditioners

  • Remove the dirty or faulty filter and replace it with a new one. Ensure that the same size air filter is used and inserted into the filter cabinet in the proper direction.
  • During the winter, check your filters once a month and replace them if necessary – it’s essential to replace filters more frequently because of increased heating use.

Blower motor problem

Your forced-air furnace can run but not deliver heat to your home if the blower motor is malfunctioning. Examine the blower and resolve the issue if necessary. In this case, you may need to contact a professional HVAC company.

  • Remove the access panel to the blower chamber and shut off the power to the furnace. Any debris blocking the fan blades or heavy dirt that could clog up the motor should be looked for. It may need to be cleaned.
  • Check the belt connecting the motor and the fan. You may be able to tighten and reposition it if it has slipped or become loose. You will need to replace it if the belt has broken.
  • You should call a professional furnace repair service if you can’t locate the blower motor problem.

How do you fix a furnace that won’t start?

Diagnosing the Problem

The first step in fixing a furnace that won’t start is to diagnose the problem. Common reasons for a furnace not to start to include a blown fuse, a tripped circuit breaker, or a malfunctioning thermostat. To check for these issues, locate your furnace’s electrical panel and inspect the fuses or circuit breakers. If you find a tripped breaker or blown a fuse, reset it or replace it as necessary. If these steps don’t resolve the issue, check the thermostat to ensure it’s set to the correct temperature and has fresh batteries.

Checking the Furnace

If the problem persists, it’s time to check the furnace itself. Ensure the furnace’s power switch is turned on, and verify that the blower motor is running. If the blower motor is not running, try turning off the power to the furnace and then turning it back on again. If the blower motor isn’t running, you may need to replace it.

Inspecting the Ignition System

Another common issue with furnaces that won’t start is a malfunctioning ignition system. If your furnace has a pilot light, check to ensure it’s lit. If the pilot light is out, follow the manufacturer’s instructions for relighting it. If the pilot light does not stay lit, you may need to replace the thermocouple, which is the device that senses the pilot light’s flame. If your furnace has an electronic ignition system, check the control board to ensure it’s functioning properly

FAQs (Frequently Asked Questions)