York Furnace Not Heating? Here’s Why (And How to Fix It)

York is known for producing high-quality furnaces that are designed to last up to 30 years. However, furnaces are complex appliances with many different components, and even the best units aren’t immune to heating issues.

If your York furnace is not heating, it’s likely due to a damaged flame sensor, malfunctioning ignitor, faulty thermostat, or faulty rollout limit switch. You may be able to fix these issues with a thorough cleaning or basic maintenance, but more complex issues will require an HVAC repair service.

Locating the issue is going to be the most challenging part of fixing your York furnace. While some models provide error codes, they don’t specify which components are broken.

To help you figure out what’s wrong, I’ll be explaining how to identify each issue. If the issue has a simple DIY fix, I’ll list the steps needed to fix each problem, and I’ll also tell you when the repair is complex or dangerous and will require calling an HVAC service.

Note: This guide includes the most common causes of a heating disruption, but furnaces are intricate appliances and the problem may be something not listed here. If fixing your furnace is an urgent matter, I recommend contacting a professional HVAC service to identify the problem and make the repairs for you.

Damaged Flame Sensor

The flame sensor in a furnace is responsible for sensing if the burner is producing a flame. When the sensor is damaged or not working, the furnace will disable the heating mechanism to prevent overheating (which can be dangerous). The furnace’s control board disables the heat by cutting off the voltage to the gas valve.

When the flame sensor is damaged or clogged with debris, it can have trouble sensing . Hence, it’s important to do yearly maintenance to help prevent this issue from occurring. Listed below is what you’ll need to do in order to clean your flame sensor.

How To Fix A York Furnace Flame Sensor

1. Start by shutting off the power to your HVAC system.
2. Using the user manual, find where your furnace’s flame sensor is located. If you don’t have the user manual, you can find the manual for your model here: York Furnace User Manuals.
3. Use a damp towel to wipe down any debris around the flame sensor. 
4. If you encounter any dirt or hard-to-remove residue, use a fine abrasive towel for effective cleaning.
5. Once you clean the unit, test to see if the sensor turns on. If it doesn’t, then you’ll need to contact a professional HVAC technician to fix or replace the component.

If you’d like a video guide on how to clean the flame sensor on your York furnace, I recommend watching this video:

Malfunctioning Ignitor

Another common issue with York furnace heaters is that the ignitor may have malfunctioned. The ignitor is what turns the fuel in your furnace into heat. When it’s damaged, the furnace won’t blow hot air, and the thermostat will stop the ignitor from turning on. 

I don’t recommend trying to fix the ignitor yourself. It’s a tricky process that requires the right parts, and if you don’t do it correctly you might end up damaging your furnace. And as a working ignitor is essential for your furnace to operate correctly, it’s important that you get it fixed as quickly as possible.

If you’d like to perform the fix yourself, here’s how to do it:

How To Fix A York Furnace Ignitor

1. Make sure to cut all power sources from the furnace, including the wall socket.
2. Locate and turn off the gas valve before cutting power to the furnace, as you don’t want any gas leaking while you work.
3. Allow the furnace to cool down, as the interior can be hot and can burn your hands if you don’t allow the panels to cool.
4. Open the thermostat panel and check to see if the temperature is set to at least 65°F (18°C). If your home’s temperature is higher than that, set it above that temperature.
5. Locate the ignitor and remove it from the panel. You will need to use a screwdriver to do this.
6. Inspect the ignitor for any cracks or damage. If the unit is cracked, then you’ll need to purchase a new ignitor. If you can’t find any signs of damage you’ll need to perform a multimeter test to check for continuity.

A Failing Wall Thermostat

If the flame sensor and ignitor look okay, the issue may be with your wall thermostat. The wall thermostat is what controls the power supply to the HVAC system. When the thermostat fails to detect any signals from the furnace, it will turn off the heat to prevent overheating.

You can figure out if your wall thermostat is defective can be done by performing a multimeter test. 

How To Fix the Wall Thermostat

To test your wall thermostat, you’ll need a digital multimeter. I recommend the AstroAI Digital Multimeter (available on Amazon.com). It’s reliable, safe, and includes helpful features like data holding and auto shut-off that other multimeters lack.

1. Grab your digital multimeter and turn the dial to ṽ or m v.
2. Take the black lead and connect it to the COM jack.
3. Take the red lead and plug it into the V jack.
4. You’ll then need to take the leads out in opposite order. Take the red one out first, then the black one.
5. Connect the leads that need to be tested into the circuit and avoid touching the lead tips with your fingers. Plug in the black lead and then follow up by plugging in the second.
6. Give the tool a few moments to give an accurate reading before checking the measurements on display.
7. Once you get a reading, remove the read lead before taking out the black lead and powering off the device.

Following these steps can be tricky, so I recommend watching this excellent demonstration of how to perform a multimeter test on your furnace:

For easy reference, here is a table of appropriate readings for system voltage ranges:

Faulty Rollout Limit Switch

Another common issue is that the rollout limit switch will prevent the furnace from heating if a problem is detected. When the inducer fan motor isn’t drawing enough air into the burners, it will shut down the system to prevent fires. 

The rollout switch will halt the ignition and stop the furnace from internally heating. Luckily, this is a common issue that can be fixed without the need for an HVAC professional.

How To Fix the Rollout Limit Switch

1. Perform a multimeter test to determine if there is continuity.
2. If the multimeter test fails, then you’ll need to identify the flame rollout switch model. This can be done by checking your instruction manual or by contacting York customer service to order a replacement.
3. Once you have the new flame rollout switch, you can swap it out for the old one.
4. If you’ve switched it and the furnace still doesn’t heat, you can try the following:
   1. Move any items surrounding the furnace and allow it to vent properly.
   2. Check the restricted exhaust vent to ensure there is proper airflow to the burner.

I’ve done my best to mention and explain the most common causes of York furnace heating issues and how to fix each of them – hopefully you were able to fix the problem without professional help. However, if you’ve checked for all of the problems mentioned above and your furnace still isn’t heating, you’ll need to hire an HVAC repair service to troubleshoot and fix the furnace for you.

Chris Hewitt

Chris is a Texas-based freelance writer who loves the outdoors and working in his garage. When he’s not enjoying the Texas sun, he can be found tinkering with all sorts of things in his workshop.