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How to Fix a Heater That Won’t Ignite: Troubleshooting Guide

January 15, 2024
Two technicians in blue uniforms, one with a Texas flag patch, inspecting an HVAC unit in a dimly lit space using a headlamp.

Tips For A Heater Not Starting

When an icy cold front blows through San Antonio, there’s nothing worse than suddenly realizing your heater is not starting. Though winters are mild compared to other parts of the country, San Antonians aren’t used to temperatures dipping into the 30s or 40s. 

Even a light freeze can send locals scrambling to find space heaters, blankets, and warm coats.

But before you panic about freezing indoor temps, there are do-it-yourself troubleshooting tips you can try to get your heater running again. Don’t resign yourself to shivering all season long – continue reading to learn a few easy DIY steps that can often get a heater running again.

Contact us at Elmer’s Heater Repair anytime your furnace needs troubleshooting or repair. Call us now at 210-570-1717 to schedule an appointment.

How To Get Your Heater Running Again 

Check Faulty Thermostat

One of the most common reasons a heater won’t start is because of a malfunctioning thermostat. If your home feels cold even though you’ve turned up the thermostat, this could indicate an issue with the device. 

Try replacing the batteries first to see if that gets things going again. If new batteries don’t do the trick, you’ll likely need a professional thermostat replacement. Give our experts a call, and we’ll get your temperature under control in no time.

Pilot Light Problems

If your furnace has a pilot light, a lack of flame here could be the culprit for a non-working heater. 

Check to see if the pilot light has gone out, and relight it if needed. However, if the pilot light won’t stay lit, that hints at a more serious issue like a clogged gas line or broken ignitor.

Our technicians have plenty of experience diagnosing pilot light problems, lightening a faulty furnace’s frustration.

Ignition Issues

For heaters without pilot lights, ignition issues often prevent operation. In this case, gas can’t flow to start combustion if the ignitor fails to spark. 

However, replacing old ignitors is usually required to get these systems firing on all cylinders. Also,  improper wiring could also inhibit ignition, so our team will thoroughly inspect electrical connections. 

Ultimately, trust us to pinpoint and fix the precise ignition problem that is leaving your heater helpless.

Clogged Air Filters

Here’s a simple potential reason your furnace fails – dirty air filters! 

Clogged filters cause airflow restrictions that can ultimately shut down your heater. So, it is always advised you check the filter first and change it if it looks dusty and covered in debris. However, while waiting for warmer air, huddle under blankets and call us to perform additional heating inspections and maintenance.

Don’t Delay – Contact the Experts at Elmer’s!

Is your house still feeling like an ice box? Don’t let the cold get you down another day – call Elmer’s Air Conditioning & Plumbing now! Our San Antonio Heater Repair team has the tools and know-how to accurately diagnose your heater problems. We’ll troubleshoot the issue, make any necessary repairs, and ensure your system is running smoothly once again. Don’t leave your comfort to chance – Contact the top experts in heating and cooling to get your furnace firing on all cylinders. Stay cozy this season with speedy heater troubleshooting from Elmer’s!

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