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3 Most Common Winter Furnace Repairs

During winter’s blast, our furnaces work overtime to keep us comfortable without much regard to age or condition. Eventually, the weakest link in a heating system will fail, creating a need for a furnace repair. While your furnace may carry a decade or longer guarantee, some of the smaller, more susceptible parts, like those listed below, may fail prematurely.

Here are the most common furnace repairs our technicians encounter each winter.

1. Igniter Failure

Igniter failure is the single most common cause of gas furnace problems we see.

Furnace igniters replaced the pilot light systems that started gas furnaces in the past. If you remember “the pilot light going out” on your old gas furnace, you know that pilot lights were inefficient and often extinguished by drafts.

Rather than an actual standing flame, modern ignitors use electricity to heat small wires or filaments until they produce a spark to ignite the gas furnace. While igniters are safer and much more energy efficient than the old pilot lights, they’re still a common source of furnace issues.

Ignitors can malfunction with age, wear and tear. A dirty or clogged ignitor can prevent your gas furnace from igniting properly.

2. Issues With the Flame Sensor

The flame sensor is another part of the furnace ignition system that is prone to failure.

Older gas furnaces had a thermocouple, which could detect the heat put off by the pilot light. If the thermocouple determined there was no pilot light, it would prevent the flow of gas to the furnace for obvious safety reasons.

Modern furnaces use a flame sensor which, in essence, serves the same purpose. A flame sensor will prevent the flow of gas into your furnace if it detects there is no ignition source like a flame ignitor. The flame sensor must perform this task dozens if not hundreds of times per day throughout the cold weather months. Over time, the flame sensor can fail due to this great demand.

3. Problems With the High-Limit Switch

Have you noticed that your furnace will kick on minutes before warmer air begins to circulate throughout your home? This is the high-limit switch at work.

The high-limit switch has the important job of keeping the blower from powering air through your home until it’s heated sufficiently. Without a functioning high-limit switch, you’d be shivering in cold, unheated air!

This is another part of your furnace that is asked to perform thousands of times through the winter and will likely eventually fail.

When To Call An HVAC Professional

While it’s possible for experienced do-it-yourselfers to complete some of these common repairs on their own, we would caution against taking on such a task if you feel at all uncomfortable. Most modern furnaces combine electricity and gas to create combustion—two elements that require caution, know-how, and appropriate safety measures. When it comes to any furnace repair, the safety of you and your family is the primary concern.

If you’re in the Greater Chicago area, schedule your furnace service online or give us a call at (815) 455-7000. Our licensed Chicago HVAC technicians can diagnose your furnace problem and get it resolved fast so you’re not left in the cold.

This information is provided as a general guideline. Althoff Industries does not assume any liability resulting from the provided information.

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