How To Change The Air Filter On Lennox Air Conditioner

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The main job of the air filter is to filter out dust and debris from your air conditioner and furnace. And you'll be surprised by how much debris can build up in just a few days.

Changing the filter regularly helps keep your home's air clean and decreases the impurities flowing through your air conditioner from the outdoors. But how do you change the filter on a Lennox air conditioner specifically? We researched this, and we'll discuss it here.

Here are the steps to change the air filter on a Lennox air conditioner:

  1. Locate the air filter
  2. Slide the air filter out of its housing
  3. Check the size of the filter
  4. Insert the new filter into the housing

The process for changing a Lennox air conditioner is relatively straightforward. However, it's always best to check your user's manual to ensure that you follow the correct procedure for removing filter covers or panels. Continue reading to learn how to get it done.

Air conditioning system unit installed outside facade of the new house, How To Change The Air Filter On Lennox Air Conditioner

Steps To Change The Air Filter On Lennox Air Conditioner

Remove dust filter from air conditioner

Lennox air conditioners typically come with a disposable air filter that is about 1-inch thick. These filters should be changed anywhere from 1 to 3 months. However, if you or anyone in your home suffers from allergies, it may be best to change them monthly.

Remember, changing the air filter regularly can help prolong the lifespan of your air conditioning unit [in addition to regular maintenance].

Things you'll need:

  • New air filter
  • Screwdriver

1. Locate the air filter

First, locate the filter area on your air conditioner. The filter is typically found on the bottom or the side of the unit, but it may be housed inside the unit, depending on the model.

If that's the case, you'll need to take off the front access panel to access it. In some cases, you'll also need to use a screwdriver to remove any fasteners holding it in place.

2. Slide the air filter out of its housing

After locating the filter, use a small pry tool such as a pry bar or a 1-inch putty knife to slide the filter out of its housing. Once you're able to grab it with your hand, pull it out completely from its position.

Remember that you may need to nudge the filter left and right if it's nestled tightly in its position. Also, take note of the direction of the filter as you remove it.

3. Check the size of the filter

The dimensions of the air filter will be located on the side of the filter. The dimensions are listed as Width x Length x Height [example 16x20x1]. Make sure that the new filter has the same dimensions as the previous filter. Otherwise, it won't fit into the housing area.

4. Insert the new filter into the housing

Next, locate the directional airflow arrows on the new filter. These arrows point in the direction of the air conditioner's airflow to show you the correct way that filter should face.

Be sure to insert it correctly with the open area of the filter facing the vent. And once you slide the filter in position, you're all set. Next, replace the front panel on the air conditioner if you've removed it.

Need a visual? Check out this helpful YouTube video:

Where is the air filter on a Lennox air conditioner?

Most Lennox air conditioners will have the air filter located either in the blower compartment of the connected furnace or in a separate attached filter case. The filter may also be found in a wall-mounted air grill vent on the return. If you're unsure of the location of your filter, check your user manual.

How many filters does an AC unit have?

Air conditioner technician servicing indoor.

Most air conditioning units come with only one filter, typically located in the furnace or near it. However, some units will come with two or more filters.

When you purchase your air conditioner, the number of filters will be located in the user manual. It will also state the type and size of the filters you'll need for the unit specifically.

What happens if the air filter is backward?

Installing the air filter backward is never a good idea. Here are a couple of problems that can develop if you install the filter in the wrong direction.

There will be issues with air circulation and filtration

As the furnace sucks in cold air from outside the home, the heat exchanger warms it and then blows it back into the living space. Any fibers, debris, and dust can enter the home through the vent and from the heat exchanger if the filter is backward.

This is something you don't want, as it can cause issues with the air quality of your home, and it's especially troublesome for anyone who has allergies.

The furnace will be less efficient

A backward air filter will also cause the furnace to work overtime to do the same amount of work. As air circulates through the furnace system, the blower will have difficulty pushing the heated air through the backward filter, as it's less porous than the other side.

The central air and furnace of the HVAC system will have to now pull air through the non-porous side of your filter, causing it to lose efficiency. This, in turn, will require the HVAC system to expend more energy and will result in a spike in your utility bills.

How do you clean a Lennox filter?

The process to clean a Lennox filter is pretty straightforward. But make sure that you have the type of filter that's to be cleaned instead of replaced. Cleanable air filters will typically have a plastic frame and a metal mesh grill. Replace filters usually have a thin cardboard frame and a white mesh polyester or cotton center. And here's how to change a Lennox filter:

1. Turn off the power to the HVAC system

First, turn off the HVAC system at the thermostat. You can also turn it off at the circuit breaker.

2. Locate and inspect the filter

Next, locate the filter housing area for your system. This will typically be located near the furnace in the front panel or a separate filter housing compartment. Refer to your user's guide to find it. Once you find it, inspect the filter to determine if it needs to be cleaned.

3. Vacuum the air filter

Next, take a small handheld vacuum or a vacuum with a hose attachment and manually clean the filter. Be sure to remove all dirt and debris from the mesh grill, and pay special attention to the corner areas where it accumulates the most.

If there is only a small amount of dirt in the filter, wipe it off with a clean cloth. However, if the filter needs a more thorough cleaning, proceed to the next steps.

4. Wash the air filter

Next, take the filter out back and spray it with a water hose with a nozzle attachment. Be sure to keep the nozzle at least 8 to 10 inches away from it so that you don't want to damage the mesh grill. If you don't have a water hose, you can also clean the filter in your kitchen sink or bathtub.

Fill the sink or bathtub with warm water and about1/4 tbsp of regular dish soap. Let the filter for about 5 to 7 minutes.

Next, take a sponge or cloth and remove any dirt and debris and go over the filter. Next, rinse the filter by running it under the cool water and then shake it to help get rid of excess water. Lastly, let the filter air dry for about 15 to 20 minutes before placing it back in its housing.

How do I reset my AC after changing the filter?

Technician repairing air conditioner

The easiest and quickest way to reset your air conditioner after changing the filter is to flip the breaker switch corresponding to the air conditioner or HVAC unit. Before changing the filter, flip the switch to the "Off" position to turn off the unit.

And after changing the filter, flip it back to the "On" position to restore the power to the air conditioner. Remember that doing so may also erase any temperature or "Auto" settings on your thermostat, so you may want to note this before performing the reset.

Wrapping things up

Aircondition service cleaning

Changing the air filter on a Lennox air conditioner is pretty much the same process as it is with other HVAC systems. Always remember to first power off the unit before performing this task. And it helps mark your calendar so that you know when to replace or clean the filter again.

Before you go, be sure to check out our other posts:

Goodman Air Conditioner Tonnage: How To Find What Yours Is

Furnace Humidifier Water Always Running – What To Do?

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