What to Check If Your Heater Isn’t Working


A malfunctioning heater during the cold months can be a real inconvenience and discomfort. Whether it’s a central heating system, a space heater, or a furnace, a non-operational heater can make your home feel unwelcoming and chilly. In this blog post, we will explore the common issues that may cause your heater to stop working and provide tips on what to check before calling a professional.

Thermostat Settings

Before you dive into more complex troubleshooting, start with the basics. Check your thermostat settings to ensure they are configured correctly. Make sure the thermostat is set to “heat” mode and the desired temperature. Sometimes, a simple oversight in programming can lead to a lack of warmth in your home.

Power Supply

Check if the heater is receiving power. If you have an electric heater, ensure it is plugged in and the power outlet is functional. For gas heaters, verify that the pilot light is on. In the case of a central heating system, ensure that the circuit breaker or fuse for the furnace is not tripped.

Dirty or Clogged Filters

Heaters, especially forced-air systems, rely on clean and unobstructed air filters to operate efficiently. Dirty or clogged filters can restrict airflow and cause the heater to work harder, potentially overheating and shutting down as a safety measure. Replace or clean the filters according to the manufacturer’s recommendations.

Fuel Supply (Gas Heaters)

If you have a gas heater or furnace, check the gas supply. Ensure the gas valve is in the open position. If you smell gas and suspect a gas leak, immediately turn off the gas supply and contact a professional technician to inspect and address the issue.

Pilot Light (Gas Heaters)

For gas heaters and furnaces, the pilot light should be consistently burning. If it goes out, the heater will not function. Relight the pilot light according to the manufacturer’s instructions. If it keeps going out, it may be a sign of a more serious issue and should be inspected by a professional.

Blower or Fan Issues

The blower or fan in your heater is responsible for circulating warm air throughout your home. If the blower is not functioning correctly, your home may not heat up as it should. Check for obstructions or debris in the blower’s path, and ensure that the blower motor is working correctly. If it isn’t, it may need to be repaired or replaced.

Circuit Breaker or Fuse Issues

If the heater suddenly stops working, it could be due to an electrical issue. Check the circuit breaker or fuse box to see if a tripped breaker or blown fuse is causing the problem. If so, reset the breaker or replace the fuse, and monitor the heater to ensure it functions properly.

Ignition Problems (Gas Heaters)

For gas heaters, ignition issues can be a common source of trouble. If the heater’s ignition system is not working correctly, it won’t be able to light the burners. Ignition problems can result from faulty components or dirty ignition sensors. It’s advisable to have a professional technician diagnose and fix these issues.


Many heaters have safety features to prevent overheating. If your heater has been running continuously or is positioned too close to obstructions, it might overheat and automatically shut down. Allow the heater to cool down and ensure it has proper ventilation to prevent overheating.

Blocked Air Vents or Registers

Obstructed air vents or registers can hinder the flow of warm air in your home. Ensure that no furniture, curtains, or objects are blocking these openings. Clear any obstructions to allow the heat to circulate freely.

Leaking Ducts

Leaky ducts can cause heated air to escape into unconditioned spaces like your attic or crawl space, reducing the efficiency of your heating system. Check for any visible leaks in your ductwork and have them sealed by a professional if necessary.

Dirty Burners

In gas furnaces, dirty burners can impede the combustion process and reduce efficiency. Over time, the burners may accumulate dust and debris, affecting their performance. If you are comfortable doing so, you can turn off the heater and clean the burners. However, it’s often best to have a technician perform this task to ensure it’s done correctly.

Thermostat Batteries

Some thermostats are battery-powered. If your thermostat isn’t displaying correctly or isn’t communicating with your heating system, it may be due to dead or low batteries. Replace the thermostat batteries and see if this resolves the issue.


When your heater isn’t working, it’s important to troubleshoot the problem before resorting to a professional service call. Many common issues, such as thermostat settings, power supply problems, and dirty filters, can be resolved with minimal effort. However, if you’ve checked all the basic elements and your heater is still not functioning correctly, it’s time to consult a qualified heating technician to diagnose and repair the issue. A well-maintained and efficiently functioning heater is essential for staying warm and comfortable during the colder months.

Need a HVAC Contractor In Colorado Springs, CO?

Welcome to Elevation Mechanical! Our technicians offer superb customer service and always see to it that your heating and cooling needs are exceeded. Customer service is a top priority for us, as we care about providing for our clients to the best of our ability. Building relationships and trust with our customers is something we take great pride in. We understand that problems with your heating, ventilation and cooling systems can lead to inconvenience and discomfort. For that reason, we will treat your problems as if they are our own. Contact us today to learn more about what we can do for you!