Heating System Does Not Ignite:
When the thermostat is properly powered and correctly set, the furnace should activate once the set temperature is reached. The thermostat triggers the furnace’s ignition system, which ignites the burners to start the heating process. If the furnace doesn’t ignite, the home receives no heat.
The pilot light is out.
Furnaces over 10 years old are often equipped with standing pilot ignition systems that utilize a constant burning pilot light. If the pilot light goes out, heating fuel is not ignited. The furnace’s owner’s manual typically includes instructions for relighting the pilot light. However, if the pilot continues to go out, check for nearby drafts. If no drafts are to blame for extinguishing the pilot, the cause may be a faulty thermocouple, which may be corrected through cleaning of the component or replacement. A bad gas regulator could be causing fuel supply issues with multiple gas appliances in the home. Contact your utility providers for immediate assistance.
Electronic ignition is dirty.
Accumulation of carbon on electric ignitors can prevent proper ignition of the furnace. A repetitive clicking noise usually occurs, which indicates the ignitor is not working correctly. Careful cleaning is needed to remove carbon. This is a fragile component, so if you feel uncomfortable doing this, please call our office at 661 270 1961.
Cracked hot surface ignitor element.
If the hot surface ignitor’s heating element has cracked, the furnace will not ignite. Typically, this component has a service life of three to five years and requires periodic replacement, though it may fail sooner when exposed to improper handling or short cycling. Careful homeowners may be able to replace this component, or you can call AC Dave Heating & Air and we can get the job done.
Ignitors sustain damage due to wear and tear, occasionally requiring replacement. To diagnose a damaged ignitor, a multimeter is used. Depending on the type of ignitor and ignition system, replacement may be a complex task and should be left to a licensed HVAC professional.
The wrong ignitor was installed.
Improper furnace installation can lead to the wrong type of ignitor being put into use. An ignitor that requires incorrect voltage can cause the ignition system to fail. Furnace troubleshooting includes replacing the component with the proper part for the furnace’s ignition.
Malfunctioning limit switch.
When operating normally, the limit switch shuts off the ignitor when the furnace reaches high temperatures. If the limit switch malfunctions, it may unnecessarily impede ignition. Poor airflow and dirty filters may also cause the ignition to be shut down prematurely by the limit switch (Replacing filters can prevent this issue and correct overheating). If the limit switch is damaged, it needs to be replaced.
Whatever your heating/cooling needs, AC Dave Heating & Air are here to serve you. Call us: 661 270 1961 Lic #877683