Lennox furnace troubleshooting  | HVAC Options

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Lennox furnace not working? You could possibly remedy the issue by yourself with some Lennox furnace troubleshooting. Earlier than you name a restore particular person, give the following tips a strive.

Lennox furnace is just not heating or not blowing sizzling air

First, verify your energy. Guarantee no switches have tripped or fuses blown. If they’ve, repair them.

Subsequent, verify your thermostat. If it takes batteries, ensure that they’re contemporary. Your system ought to be on “warmth” and “auto.” Selecting on “on” as an alternative of “auto,” will make the furnace consistently blow air whether or not or not it’s actively heating.

Verify the temperature setting. If somebody’s lowered it, the warmth received’t begin till the house temperature dips beneath that setting.

Subsequent, take a look at your air filter. If it’s filled with mud, change it. You need to change your Lennox furnace filter frequently. You possibly can decide one up inexpensively on Amazon or at a retailer like Goal. Our information demonstrates the best way to change your furnace filter. 

Lastly, clear the within of your furnace. Flip off the facility to the unit and open the duvet. Gently mud the parts inside with a smooth material or canned air. 

If these Lennox furnace troubleshooting steps don’t work, name a technician. You’ll have an issue together with your fuel valve or blower motor panel. These aren’t DIY fixes. 

Lennox furnace is constantly operating

In case your furnace consistently runs, you seemingly want a brand new filter. See the above query for data on altering your furnace filter.

If that doesn’t assist, verify your thermostat. If you happen to set it to “on” as an alternative of “auto,” the fan will run consistently. Change it to “auto” and see if that resolves the problem.

Subsequent, ensure that there are not any air leaks in your home. Vitality.gov has good tips about how to do that. If you happen to discover any, restore with caulk or weatherstripping. 

Lastly, guarantee your ductwork is freed from obstructions and leaks. You possibly can see into your ducts by opening your registers and utilizing a flashlight. Or you’ll be able to rent knowledgeable to examine and clear your ducts.

If you happen to nonetheless can’t get your Lennox furnace to cease operating, name an HVAC professional. You’ll have a defective restrict change.

Lennox furnace is beginning and stopping

This sample is often referred to as “quick biking.” In case your Lennox furnace is brief biking, be sure to set your furnace to “warmth” and “auto.”

Subsequent, verify your air filter. See directions above on the best way to refresh your furnace filter.

Then, verify your property for drafts and potential air leaks. See above for suggestions. Additionally, verify your duct work.

Final, study your flue. The flue is the tube that leads out of your furnace to the skin of your property for air flow. Guarantee it’s not blocked or clogged by issues like a snowdrift or animal’s nest.

If these Lennox furnace troubleshooting suggestions don’t work, you could have a difficulty together with your flame sensor, warmth exchanger, or igniter. A licensed HVAC technician can examine and probably change or restore these items if mandatory.

Lennox furnace is leaking water

In case your furnace is leaking water, shut off the furnace and switch off the associated breaker. Use an outdated towel to absorb the water. If there’s quite a bit, use a store vac. 

When you’ve got a whole-home humidifier hooked up to your furnace, it could be what’s leaking water. If it appears to be like like that’s the water supply, observe our humidifier troubleshooting information.  

Verify your furnace filter. Exchange it if mandatory (see above for directions). A unclean filter could limit airflow and trigger a coil to freeze. Because it melts, it could leak water.

Alternatively, your warmth alternate could also be creating condensation. This water usually leaves the furnace by way of pipes that result in a ground drain. If you happen to’re comfy accessing these pipes, you should utilize a wire brush to scrub out any clogs. 

If these fixes don’t work, name knowledgeable. They’ll pinpoint the problem and get it fastened.

Lennox furnace error codes

In case your furnace isn’t working, its error lights could provide you with a clue about what’s incorrect. On most Lennox furnaces, you’ll be able to take away the entrance cowl. There can be a spherical glass within the backside compartment by way of which you’ll be able to see a crimson or inexperienced gentle.

The mix of those lights and whether or not they’re on, off, or flashing imply various things. See the desk beneath to decode these error lights.

Word: “Quick flash” means the sunshine blinks as soon as each second. “Sluggish flash” means the sunshine blinks each three seconds.

Lennox furnace troubleshooting sources

Lennox has a furnace troubleshooting software on its web site which will allow you to determine and remedy points together with your system. The corporate additionally has a product literature look-up to view the proprietor’s guide to your mannequin. 

Each of those Lennox furnace troubleshooting sources could allow you to find components. They’ll additionally allow you to determine if it’s greatest to name a technician or try a DIY repair.

If you happen to’ve tried the entire suggestions and sources above and nonetheless can’t repair the issue, contemplate calling an authorized HVAC skilled. Or, for those who’re not comfy performing any of the troubleshooting duties, knowledgeable can do them for you. Click on beneath to attach with knowledgeable who will help get your furnace again in form.