Why does my furnace keep running

Have a furnace fan that runs continuously?

First, try this: Make sure your thermostat fan setting is on AUTO not ON. Then, turn the thermostat to a temperature that’s lower than the current room temperature and wait 3 to 4 minutes.

Furnace fan still running? Well, that’s not normal. If your furnace fan won’t turn off, you most likely have one of these 3 problems:

• Your furnace fan limit switch is set to “manual override”
• The fan limit switch is faulty and needs to be replaced
• There’s a problem in your thermostat wiring

Unfortunately, you’ll need a professional to fix those last 2 problems. But before you call in a pro, check to see if your fan limit switch is set correctly. We’ll show you how to do that in this article.

Need a professional ASAP? Just contact us and we can get your furnace fan running normally in no time.

Step 1: Locate your fan limit switch

Your fan limit switch is located inside the furnace panel cover, usually near the upper right corner.

The fan limit switch is responsible for turning the blower on and off at the appropriate times. So, when the switch is working correctly, your furnace fan should turn on several minutes after thermostat calls for heat and turn off several minutes after the heat cycle ends.

But if the furnace fan runs continuously, regardless of whether the furnace is heating or not, your furnace fan limit switch is either:

• Set incorrectly to Manual or
• Faulty and needs to be repaired/replaced

Now that you’ve located your fan limit switch, let’s look at how you can determine whether it’s set correctly or not.

Step 2: Make sure the white button is NOT pressed in

Your fan limit switch will have a small white button on the lower left corner. That button tells the switch whether to operate manually (run the fan all the time) or automatically (run the fan only during heating cycles).

If the button is pressed in, the switch is set to Manual and is forcing the fan to run continuously. You’ll need to reset it to AUTO to allow for proper fan operation (see pic below for instructions).

Step 3: Call a professional if the fan is still running

If your fan limit switch is set to AUTO but the fan continues to run without ever stopping, you’ll need to call a professional.

Two problems that could cause your fan to run without stopping include:

• A bad fan limit switch that needs to be replaced
• Bad thermostat wiring

Need help from an Atlanta furnace tech?

If you’re still having trouble with a furnace fan that won’t shut off, we’re here to help.

Just contact us and we’ll send out an experienced tech as soon as possible.

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Is your furnace blowing air nonstop? If so, you’re probably feeling a bit concerned. First, your house most likely feels like an oven. On top of that, your utility bill will be considerably higher with your furnace running constantly. Believe it or not, this is a fairly common problem, so you don’t need to worry.

Before calling a technician, check these three things:

1. Be sure you have the right thermostat settings

Be sure your thermostat is set to a reasonable temperature. Energy Star® recommends keeping it at 68 degrees Fahrenheit during the winter to save on utility costs. If you set your thermostat to ultra-high temperatures, this may cause it to run constantly. Additionally, be sure to set your thermostat to Auto instead of On. The On setting causes it run constantly, instead of incrementally.

2. Check the filter

If you haven’t changed your furnace filter in a while, this could be the source of the problem. Over time, dust and debris clog your filter. This constricts airflow, which means the furnace has to work extra hard to maintain the desired temperature. Depending on how clogged the filter is, it may have your unit running nonstop.

3. Check the pilot light

If the pilot light underneath the furnace is out, it can’t generate heat. In many cases, this causes your furnace to run continuously, because it can’t reach the desired temperature. If the pilot light goes out again, call one of our expert technicians.

If none of the previous steps worked, schedule a repair with us at Adams Heating & Cooling. Here are three potential problems requiring our professional help:

1. Leaky ducts

If any of your ducts are punctured or blocked, this means heat isn’t being circulated properly. You’re losing heat and losing money through your utilities at the end of the month. A technician can run a thermal analysis to determine the location of the leaks and repair your ductwork.

2. Broken fan motor

When your fan motor is obstructed, broken, or otherwise faulty, it can’t operate at full capacity. That means it has to run continuously to reach the set temperature. Unusual noises from your furnace are a sign you have a broken motor.

3. Thermostat malfunction

Your thermostat is the brain of the operation. When it sends the wrong information to your furnace, a number of things can go bad. You could have a broken relay switch, or your thermostat could be producing an inaccurate temperature reading.

We want our neighbors here in Anderson Township, OH to come home to a happy, healthy furnace every night this season. To restore your unit to optimal condition, call Adams Heating & Cooling at 513-474-1600.

When it comes to HVAC systems, you already have a lot to worry about. All the minor details can make a huge difference in how your system runs and how long it lasts. Today we’re going to discuss what to do when your furnace fan keeps running. This problem is probably one of the more minor problems that you address on your own.

When you hear that your furnace fan is running continuously, the first step is to check the thermostat. If the fan setting is set to ON and not AUTO, that may be the source of the issue. All you’ll need to do to resolve the issue is set the fan to AUTO and then turn the thermostat lower than the current temperature. You’ll likely find that the fan will stop spinning within a couple minutes and BAM, problem solved.

However, if this method is not the source of the problem, you should then check for the following three potential problems:

1. The furnace fan limit is set to “manual”.
2. There is a problems with the thermostat wiring.
3. The fan limit switch needs to be replaced.

Sadly, you will need a professional to solve some of those issues, but first you can locate your fan limit switch. It’s located inside your furnace panel near the top right corner. What does your fan limit switch do? Well, it’s responsible for turning the blower on and off when you ask it to. When the switch works correctly, your fan should turn on a few minutes after your adjust your thermostat accordingly and turn off again once the cycle is over.

So if you’re not using the thermostat to constantly turn on the cycle, but the fan keeps spinning, your limit switch is probably set to the manual setting or needs a replacement. Now that you have found the switch, you can determine whether or not you need to call your HVAC repair. There should be a white button in the lower left corner that should not be pressed inwards. If it is, your system is set to manual and forcing the fan to run on a continuous cycle. You’ll need to set it back to AUTO in order to allow the correct fan operation.

If neither of these two solutions work, it’s time to call for a professional. If you’re still having issues with your furnace fan refusing to shut off, ProFlo is here to assist. Give us a call and we can make sure your HVAC system runs smoothly once again.

Possible Causes for a Furnace that Won’t Turn Off:

• Blower issues. Is the air coming from your vents warm or cool? If your furnace is running but you’re only getting cool air, you may have a blower issue. It’s possible that an electrical issue is causing your blower to constantly run, like corroded wires. Do not attempt to work on the electrical components of your furnace yourself. Stay safe and call an HVAC professional for repairs.
• Dirty/clogged filters. If the air coming from your vents is warm, but the air flow is weak, it’s likely your filters are clogged with dirt and dust. Clogged filters keep the necessary air from getting into your furnace, resulting in failure to adequately reach your desired indoor temperature. Replace your filters with new clean ones and see if the problem corrects itself. If not, call for furnace repair in Burlington, NC.
• Thermostat issues. Make sure your thermostat is set to your desired indoor temperature and that it is set to the “auto” setting, not the “on” setting. “On” tells your furnace to run constantly. “Auto” tells your furnace to run until the desired temperature is reached. It will then shut off automatically until the temperature falls below the set temperature, in which case it will turn on again. If your thermostat settings seem correct, but the furnace continues to run, it’s possible you have a faulty thermostat. Call an HVAC technician to inspect, calibrate, or possibly replace it.
• Pilot light issues. Old furnaces sometimes have a pilot light that is supposed to stay lit throughout the cold season. If this goes out, you may find your furnace constantly running and blowing only cool air. You can relight your pilot following the instructions for you furnace. Most furnaces these days have electric start pilots that light automatically when the furnace calls for heat. It’s possible that somewhere within that mechanism there is an issue causing the pilot not to light. This can be repaired by your heating repair service.

Furnace Repair in Burlington, NC, is Fast and Reliable

When your furnace is blowing cool air on a cold winter night or it keeps pumping heat without mercy, your home can become quite uncomfortable. If you find yourself in this situation, you need fast action. Alamance Oil Company responds quickly and offers reliable solutions to your furnace problems. Don’t suffer from the effects of a furnace that’s gone rogue. Call Alamance Oil Company at (336)226-9371 right away for furnace repair in Burlington, NC.