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My Heating Won’t Turn Off: What’s Going On?

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It’s frustrating when you find that the heating won’t turn off and your furnace is running nonstop. Could it be something simple that you can fix yourself? It’s possible, and it’s always a good idea to check the simplest things first.

Thermostat Setting Is Too High

You might have accidentally set the thermostat to a temperature that’s too high. The heater then has to work overtime to make the house warmer than it needs to be.

Fan Set to On

Or maybe the fan setting on your thermostat was accidentally switched from “Auto” to “On,”. This causes the furnace blower to run constantly. Switching it back to Auto allows the furnace to cycle on and off again as needed to keep your house at the temperature that you set on the thermostat.

It’s important to note that your furnace itself isn’t actually running nonstop when you set the fan to On. Only the blower runs continuously on that setting. Still, it should be set to Auto so that your heating system can run optimally and not continuously. This will save you money on electricity, and it will also help you save money in the future by keeping your blower from burning out from overuse.

Dirty Air Filters

Dirty air filters are another common cause of heaters running nonstop that’s easy to address on your own. A dirty, clogged air filter blocks the flow of air through your heating system. This prevents the furnace can’t run efficiently. Fortunately, this is another simple issue to resolve on your own. Simply replace your air filters when they start to look dusty or dirty. In most homes, this is about once a month. If you have indoor pets, you might need to replace your filters a little more often due to the increased fur and dust in your home.

Sometimes it’s simple to figure out the problem when your heating won’t turn off, and fix it yourself. Other times, there’s a problem that needs professional help. A heater that runs constantly is a waste of money and electricity. This situation can also lead to costly repairs in the future when components of your heating system burn out prematurely.

If your heater won’t turn off and the problem is not the thermostat’s settings or a dirty air filter, it’s time to reach out to a heating specialist. There are several potential problems that are more complicated, any one of which could be causing your heater to run nonstop. A licensed, reputable heating professional will be able to figure out what the issue is and fix it. They will also be able to give you tips about avoiding the same problem happening again in the future.

A Malfunctioning Thermostat

Another cause is a malfunctioning thermostat, and this is definitely more complicated to fix. Sometimes, the thermostat connected to your heating and cooling system goes bad. The internal wiring might have shorted out or just gotten too old to work correctly. If this is the case, you may need to have your thermostat replaced.

A malfunctioning thermostat isn’t a good issue to try to diagnose or fix on your own, since it carries too much risk of injury. Electrical problems are definitely within the domain of a professional, not a DIY homeowner. It’s best to reach out to a pro if you suspect your heating and cooling system’s thermostat may not be working right.

Two other common problems that cause a heater to run constantly are leaky ductwork and a bad blower. Like a malfunctioning thermostat, both of these should be addressed by a heating professional. A professional can diagnose the heating problem accurately and get it fixed correctly. This will save you both money and trouble in the long run.

Both of these are more in-depth issues that deserve a little more explanation, so let’s explore each one in its own section below.

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Possible Heating Problem: Leaky Ductwork

Leaky ductwork is another common cause of a heating system that stays on continuously. If you look at the ductwork connected to your furnace, you’ll see that there are ducts leading out of two separate sections or sides of the furnace. This is because there are two kinds of ductwork. There are supply ducts, which carry heated air to the rooms in your house. There are also return ducts, which pull air back to the furnace so it can heat up and then cycle through the home again.

Both types of ductwork can degrade over time, leading to leaks. Leaks in ductwork are usually in the form of small slits or gaps that form in the seams of the ducts. Leaks might also happen because of problems with the insulation around the ducts. (Insulation can also go bad over time.)

Signs of Leaky Ductwork

There are several signs that can indicate that leaks in your heating system’s ductwork are causing your problem. A heater that runs constantly is one sign. Certain rooms that never warm up, no matter how long the heater runs, is another. Higher electricity bills can also be a sign of leaky ductwork. That said, any inefficiencies in the heating and cooling system will lead to higher bills over time. If your heating system is on the older side, it’s a good idea to get it checked over by a heating professional. A professional can diagnose existing problems and head off potential issues as well.

Ductwork leaks can be tricky to find and even trickier to access, much less to fix. Heating specialists have the expertise to determine if leaky ductwork is causing your heater to run constantly. They can safely access areas of the ductwork that most homeowners can’t reach. Once there, they can either repair the leak or replace the ductwork altogether.

Even if your heater isn’t broken, it’s a good idea to have your system checked to keep it running well. A licensed, reputable heating specialist can set up a schedule to clean and inspect your entire system. They will service the outdoor units as well as the indoor components and ductwork. Lots of major repairs happen when parts go bad that could have been avoided with regular maintenance. Hiring a heating specialist for regular cleaning and checkups can keep your system in great shape and allow the specialist to head off heating problems before they develop.

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Bad Blower Motor Symptoms

The part of your furnace that pushes heated or cooled air throughout your home is the blower. The blower has several parts that can malfunction or go bad over time, including the motor. The most common bad blower motor symptoms are a heater that won’t run at all. But, sometimes, a bad blower can cause the opposite problem, making the heater run constantly.

How can you know if your blower’s motor has gone bad? If there is no air blowing out of the vents, or very little air, it can mean the blower is broken. But again, a heater that won’t turn off can also indicate a bad blower. If your heater runs constantly, it might be because of a bad fan limit switch within the blower. When this switch goes bad, the blower doesn’t receive the right signal when it’s time to turn off, so it just keeps running.

If you smell a burning smell coming from your system, that can be a sure sign that the blower motor is burning out. Strange noises when the heater is running, such as a screeching or banging sound, can also be signs of a bad blower. So can rising heating bills that indicate the system isn’t running efficiently. (This sign is one you would notice over the course of several months, rather than over the course of a day or a week.)

How Do You Fix a Bad Blower Motor?

A heating specialist is the best person to determine whether the heating system’s blower is going bad, or if there might be some other part of the heating system that is causing it not to run properly. This is partly because the blower has so many smaller components. A trained professional can figure out which part of the blower is malfunctioning and why. They can determine whether a particular part needs repairing, or if it’s better to replace the blower altogether.

Another reason why it’s best to leave blower problems to the professionals is that the blower has both mechanical and electric parts, and the furnace as a whole runs off both electricity and either gas or propane. These are all dangerous things for non-professionals to come into contact with. There are lots of safety risks involved with fixing a broken furnace blower, which is why it’s always best to hire a trained professional to handle this type of complicated heating repair. This is also why it’s a good idea to hire a heating professional for regular maintenance visits, so you can be sure your heating system is running at peak performance.

ABC Can Repair and Maintain Your Heater

Heating problems can lead to higher electricity bills, parts wearing out early and an uncomfortable home. If you’re experiencing heating issues, contact ABC Home & Commercial Services. Our licensed professionals will be able to quickly get to the bottom of your problem and make all needed repairs.

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