Furnaces are amazing, modern technological marvels that kick into action as soon as you turn them on — or at least they should. A bad furnace can strike at any time and result from one of many different problems. For instance, did you know that a bad thermostat can cause a furnace to fail?

Leith Heating & Cooling is here to answer the question, “Can a bad thermostat cause a furnace not to work?” We’re Elgin’s trusted furnace repair experts with years of experience helping homeowners whip their furnaces back into shape. You’ll learn some of the causes of bad thermostats, how they impact furnace functioning, and what common signs you should look out for if you think your furnace isn’t working right.

1. Miscalibration

As fascinating and impressive as thermostats are, they’re awfully finicky little things. It’s all too common for them to become miscalibrated and incapable of working right. Oftentimes, your furnace’s thermostat will incorrectly read your home’s temperature as hotter or colder than it actually is, especially if it’s located near a window or a vent that could mess with its readings.

Miscalibrated thermostats wreak all kinds of havoc on furnaces, turning them on and off at improper times. You might find yourself getting blasted with heat when you don’t want it, only to be left stranded in the cold when you actually need that warmth. Even worse, if your furnace is running when you don’t need it to, this ineffective heating can spike your utility bills and maybe even damage your furnace!

Get in touch with your local HVAC professionals if you suspect you’re having a miscalibration issue. Sometimes, it might be best to consider purchasing an energy-efficient furnace to help avoid thermostat problems.

2. Bad Wiring

Your thermostat relies on a complex, fascinating network of wires for its electrical supply. However, when these wires are old or just plain bad, your thermostat’s bound to fail. Perhaps it’ll work occasionally, but it’s all too common for bad wiring to cause thermostats to fail completely.

Unfortunately, furnaces without a proper thermostat can go haywire and turn on and off frequently. While you might think you can fix these wiring issues on your own, it’s best to call some experienced technicians to have them check it out. They’ll know how to address a potential issue in a safe and effective fashion.

3. Display Issues

Almost all modern thermostats use a digital display to illustrate your home’s temperature settings. In fact, many smart, programmable thermostats go a step further, connecting to your smartphone to give you remote access to your unit. However, you might not be able to use that technology if your central unit’s having display issues.

Most of the time, display issues occur when your thermostat’s low on power. Check your thermostat’s power supply, and replace its batteries if it uses those. Unfortunately, if your unit doesn’t use batteries and instead relies on your home’s central power supply, you’ve probably got some wiring issues that you’ll need professional help for.

4. Debris Buildup

Any high-quality thermostat requires regular and dedicated maintenance to work. However, neglected thermostats often accumulate dust and other nasty particulates that won’t just make you sneeze like crazy. In fact, dust buildup is one of the main causes of faulty thermostats.

Get yourself some high-quality cloths and cleaning equipment, and then turn your thermostat off before removing its cover brace. Take extra care not to damage any wires or electrical pieces, removing any dust from your unit’s coils and switches. Finally, don’t just clean it when it’s set to the lowest temperature possible! Repeat the process when it’s set to a high temperature.

5. Broken Heat Anticipator

If you own an older mechanical thermostat, your unit has this metallic piece called a heat anticipator. The heat anticipator is what tells your furnace to shut down once you reach your desired temperature.

A bad heat anticipator can cause all sorts of problems, like short cycling and overheating. If you’ve got one, you need to take care of it! However, if you’ve got a more modern digital or smart thermostat, they use factory-made anticipators that don’t malfunction much, so you should be good.

6. Thermostat-Furnace Mismatch

This problem isn’t one people usually think of when asking, “Can a bad thermostat cause a furnace not to work?”

It’s all too common for homeowners to install furnaces that don’t work well with their thermostats. For instance, a thermostat that’s got too low of a voltage rating can’t work well with a huge furnace, as it will lead to overheating and eventual failure. Consider contacting your local HVAC professionals if you see this problem.

Signs of a Bad Thermostat

Keep an eye out for the following signs that you might have a thermostat problem.

Poor Air Quality

Does your home’s air supply seem off lately? Are you curious as to why you’re always coughing and wheezing or feeling extra warm? Broken thermostats often cause furnaces so much grief that your unit won’t be able to work right. Under these circumstances, it’s not unheard of for furnaces to produce extra pollutants that can make your air supply nasty and gross.

Bad Heating

If you’re struggling to get your furnace to heat your home the way it should, consider whether or not your thermostat is bad. A bad thermostat can cause your furnace to shut off prematurely or may even stop the heating cycle entirely.

Strange Noises

It’s totally normal for furnaces to make some mild noise here and there. However, if you hear loud crashing or booming noises, or perhaps weird squeals coming from your unit, you shouldn’t think twice about calling some HVAC experts.

Elgin’s Professional Furnace Repair Experts

Are you still asking, “Can a bad thermostat cause a furnace not to work?” Give the experts at Leith Heating & Cooling a call! We’re always here to help you fix your furnace circuit board and thermostat, no matter what. Contact us at (847) 851-8698 today!

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