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Here’s Why Your Furnace Won’t Stop Running

Cassie Pound, owner of Quality Heating, Cooling, Plumbing & Electric
Published by
Cassie Pound
November 30, 2023
Here’s Why Your Furnace Won’t Stop Running

If you need high-quality heating, cooling, and plumbing services in Tulsa, Oklahoma, and its surrounds, we’re here for you!

Your furnace is an important part of your home, keeping your family warm and cozy, but what happens when it stops working? One common issue with heating units is inconsistent cycling, where it randomly stops or continues running without ever switching off. If you’re wondering why your furnace won’t stop running like this and what to do about it, you’re in the right place.

As a leading heating contractor in Tulsa, OK, Quality Heating, Cooling, & Plumbing shares possible reasons your furnace is constantly running and how to proceed.

1 The Thermostat Isn’t Set Correctly

The first step in addressing a furnace that keeps cycling is addressing the cause. While there are several factors that cause a furnace to cycle over and over again, the most common cause of an overactive furnace is a thermostat setting that’s gone wrong.

When you notice your heating unit running inconsistently, the first thing you’ll want to do is check the thermostat. Sometimes, the simplest answer is the right one, and someone in the house may well have set the thermostat too high without realizing it. Of course, this is the easiest possible fix, as all you do is return the thermostat to the desired temperature.

Another issue is the Auto vs. On setting that controls your furnace blower motor. Your thermostat should always be set to Auto so that the furnace blower only turns on when the furnace itself does. When your furnace is set to On, the blower won’t stop running.

2 The Heating Unit’s Filters Are Dirty

When was the last time your HVAC filters got a thorough cleaning? Clearing these filters of gunk and dirt is essential for maintaining heater function, as air cannot flow freely through dirty or clogged filters. If the filter restricts the unit’s airflow, the furnace will also continue running because it won’t ever reach the right temperature. 

Is your heating unit running all of the time? Check your furnace’s filters to rule out clogs. Then, to clean your heating filters and restore adequate airflow, follow these three easy steps:

  1. Open the compartment cover and remove the old, clogged filter from the heating unit.
  2. Insert a new, clean filter into the unit according to the arrows on the frame.
  3. Close the filter access panel on your unit and throw away the old filter.

Some units have reusable heating filters that you will clean instead of throwing away. If your unit has one of these, remove the filter from the furnace and use a vacuum to gently suction the debris from the filter. Whether it’s reusable or disposable, you should clean or replace your furnace’s filters at least once a month to ensure it runs correctly.

3 The Thermostat Batteries Need Changing

If your furnace won’t stop running after clearing the filter, your thermostat may still be the cause. Even with the correct settings, your thermostat can’t control the HVAC unit properly if its batteries are dying or there’s some problem with the signal between the two. 

Does your home have a programmable thermostat that uses batteries? If you’re finding the furnace is constantly cycling, try putting new batteries into the thermostat and see if that resolves the issue.

In other cases, the thermostat could be malfunctioning, broken, or outdated. Thermostats play a very important role in our home climate control systems, but they are simple pieces of equipment. It’s always possible that the thermostat can no longer control your HVAC systems, especially if it’s past its time for replacement.

4 There’s a Short in the Control Board Wiring

The warmth of your heating unit is more than welcome when temperatures drop very low, but no one wants their furnace to run non-stop. Sometimes, the cause of your furnace or heating unit problem is an electrical issue. For example, there might be a fused contact or a short in the unit’s control board.

When your furnace won’t stop running, it presents several concerns that may include the following:

Compromised Comfort

The most obvious reason you don’t want your furnace running all of the time is the toll it takes on your home comfort. A furnace that is running all the time makes any home too hot.

High Cost

An HVAC unit that overworks itself drives up utility bills, often drastically. When your furnace won’t stop running, you’ll see a spike in the following month’s costs.

Excess Energy Use

Being more sustainable and eco-friendly isn’t possible with a heating unit that runs constantly. It uses far more energy.

Fire Hazards

The most serious concern from a furnace that runs all day is a potential fire. Clogged filters and electrical issues put the safety of your family and pets in jeopardy as they overheat your machine. Since only an HVAC professional can diagnose these types of concerns, you shouldn’t wait to call local experts like Quality Heating, Cooling, & Plumbing right away if you want peace of mind.

5 Your System Has Air Duct Leakage

When your furnace is on, hot air flows through your home’s elaborate ductwork. Older homes or outdated heating units are prone to leaky air ducts, which stop air from flowing to the various spaces throughout your home. The result is a furnace that continues running at all times because it’s trying to warm your home to no avail.

If you have an older home or an old furnace, ductwork leaks may not be the only problem with your cooling and heating system. Thankfully, a team like Quality Heating, Cooling, & Plumbing can help you address these concerns promptly and reach into the ductwork as needed. Air ducts lie within the walls and ceilings of your house, so trained and equipped technicians will carefully examine these spaces to solve your heating problem as quickly as possible.

6 There’s a Larger Problem That Needs Repair or Replacement

What should you do when your furnace won’t stop running? If you notice this issue has continued after you’ve checked your thermostat settings and looked at the filters to make sure they are clean, you may need to acknowledge the likelihood of a bigger issue. 

The experts at Quality Heating, Cooling & Plumbing recommend trying the following before you call a professional for urgent assistance:

  • Turn your furnace off by going to the breaker box and turning off your heating unit. 
  • You do this by locating the “Furnace” or “Heater” label and shutting down the power. 
  • Next, you’ll want to turn off the furnace itself. The switch looks similar to a light switch and usually flips down to turn off the system. 
  • Finally, seek professional assistance to diagnose and treat the underlying problem before you use your unit again.

You might be lucky enough to have one leaky air duct or a minor electrical issue, but you’ll need to be sure before you keep running your unit.

When Your Furnace Won’t Stop Running, You Need Quality Furnace Repair Right Away!

Is your furnace running all day and night? Even with winter’s cold air, your heating unit is not meant to run constantly. Furnaces that won’t stop cycling drive up utility costs and present a safety hazard for your home. If there are signs you have a broken furnace, be sure to contact professionals near you like Quality Heating, Cooling, & Plumbing. 

When your furnace won’t stop running, you need a competent team of HVAC technicians to visit your home and check your heating system from top to bottom. Why not schedule an appointment with Quality Heating, Cooling & Plumbing at 918-393-4204 today? 

Cassie Pound, owner of Quality Heating, Cooling, Plumbing & Electric
Published by
Cassie Pound

Cassie Pound is the Vice President of Quality Heating, Cooling, Plumbing & Electric with locations in Tulsa, Glenpool, and Bartlesville, Oklahoma.