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Where is the Air Filter in My HVAC System?

Where is the Air Filter in My HVAC System?

Tips for locating the air filter based on your type of HVAC system

Bravo for wanting to change your air filter! That’s the first step to improving the air quality in your home, helping your HVAC system run more efficiently and saving money on energy costs.

The next step can be trickier — finding the air filter. It may be difficult to locate on some HVAC systems, but you can usually find the air filter in the return air duct. Or in layman’s terms, that big metal grate on your wall, floor, ceiling or utility closet door. Return air ducts can be just about anywhere.

Unlike the smaller ducts around your home, the return air duct or blower compartment pulls in the air from your home and sends it to your HVAC unit to be heated or cooled. It’s important to have a good air filter installed to trap allergens and other irritants, so they don’t get circulated around your home.

Here are some of the most common locations for an HVAC air filter.



  • Horizontal HVAC units
    Horizontal units are frequently located in attics, large basements or garages. The filter usually fits in a slot on the air return side of the unit.
  • Vertical HVAC units
    These systems are usually found in smaller basements or crawl spaces where space is limited. The filter typically slides into a slot above or below the HVAC unit.
  • Other HVAC systems
    For any other kind of system, look for the air filter behind the return air grill on the wall, ceiling or utility closet door.

Don’t forget, some HVAC systems have a return in each room. So there may be an air filter behind each of those return grills.

Finding your air return ducts can be a bit like a scavenger hunt. But it’s worth the effort to walk around your entire house, looking high and low. Be sure to check behind doors and other hidden places, so you don’t miss one.

5 Air Conditioning Myths That Are Costing You Money

5 Air Conditioning Myths That Are Costing You Money

Don’t waste your energy on these common beliefs

Want to save money on your air conditioning expenses and energy bills? Then don’t buy into these common A/C myths.

  1. MYTH: The Size of Your A/C Unit Isn’t Important

FACT: The size of your HVAC unit depends on the size of your space. A too-small air conditioning system will have to work harder to cool your home and wear down sooner. A too-large system will keep turning off and on until it breaks down. Check with a specialist who can help you choose the right size HVAC unit for your home.

  1. MYTH: Turn the Temperature Down for Quicker Cooling

FACT: Your air conditioning unit works just as hard whether you lower it 3 degrees or 30 degrees — getting to the temperature you want is just a matter of time. If you set it lower than you need to and forget about it, you’ll end up paying a higher bill. Try using a programmable thermostat or smart thermostat to save money and get the temperature you actually want.

  1. MYTH: You Don’t Need to Change the Air Filters

FACT: You may vacuum your home on a regular basis, but it’s still important to check your air filters. Air filters are typically inexpensive and can save you money on repair costs and your electric bill in the long run. If you have trouble finding your air filter or replacing it, call a specialist to help you with replacement every 30-90 days.

Air Conditioners

  1. MYTH: Run Your HVAC System Until It Quits

FACT: You’ll often hear this myth regarding cars, but it applies to HVAC units, too. Replacing an air conditioner might be more expensive up front, but running your unit past its expiration date will be less efficient and cost you money in the long run on repairs. Start saving money on your energy bills sooner by replacing your old unit before it quits on you.

  1. MYTH: Maintenance Doesn’t Matter

FACT: Broken units are inefficient units, so keep your HVAC unit performing at its peak. What might seem like a minor issue now could become an expensive one later if you don’t repair it.

5 Common Myths About Furnaces That Aren’t True

5 Common Myths About Furnaces That Aren’t True

We’re putting some heat on these winter furnace myths

Cooler weather doesn’t have to mean higher heating bills. Don’t fuel the fire of bad information— save your furnace and your wallet by separating fact from fiction.

  1. FICTION: Close Your Vents to Close Off Heat

FACT: It almost feels like common sense to close the vents to rooms you don’t need to be heated, but your furnace distributes heat equally throughout your home no matter what. Closing the vents to unused rooms only makes your furnace work harder and less efficiently— keep them open to keep air flowing freely.

  1. FICTION: It’s Normal to Have Cold Feet

FACT: Having cold floors in the winter means your home isn’t well-insulated, allowing the hot air you pay for to get out. Check the sealing around doors and windows, or hire a professional to properly seal your home so you can walk around comfortably.

  1. FICTION: All You Need is Efficiency

FACT: Having an efficient system is important if you’re trying to lower your bills, but it doesn’t mean anything if your home isn’t optimized for heating. Aside from checking your insulation around doors and windows, contact an HVAC expert to inspect ductwork, fix leaks and keep the warm air inside.

  1. FICTION: Run Your System Into the Ground

FACT: If your old furnace is breaking down, you might be tempted to just replace the bad parts until it finally quits. Replacing a furnace may seem expensive up front, but creating a frankenfurnace only causes your old system to work less efficiently and drive up your power bills. Find a new winter furnace that runs on less energy and fits your family’s budget.


  1. FICTION: Maintenance Isn’t Mandatory

FACT: Don’t let small problems turn into large bills. Regular maintenance is necessary to keep your furnace in top shape.

5 Common Misconceptions About Heat Pumps

5 Common Misconceptions About Heat Pumps

Don’t waste time or money believing the biggest heat pump myths

Heat pumps purchases are on the rise with smart homeowners looking toward more energy-efficient options, but there’s a lot of misinformation surrounding these versatile heating and cooling systems. Let’s clear the air with these heat pump facts, so you can make your home and monthly energy bills more comfortable.

  1. MISCONCEPTION: Heat Pumps Are Only for Heating

 TRUTH: Although people typically think of heating when it comes to heat pumps, names can be misleading. Heat pumps use a mechanical-compression refrigeration system that can either heat or cool your home depending on the season. This means you only need one system year-round to maintain a comfortable temperature indoors.

heat pump

  1. MISCONCEPTION: They’ll Burn a Hole in Your Wallet

 TRUTH: Heat pumps can help you save over 30% on your energy bill, compared to other conventional heating systems. While the upfront cost may be more than other options, an efficient heat pump paired with proper insulation will save you money in the long run.

  1. MISCONCEPTION: You’ll Need Earplugs Indoors

TRUTH: Heat pumps used to be pretty noisy, but modern air pump technology has evolved into much quieter systems. As long as your heat pump is properly installed by a professional, you shouldn’t have any issues with excess noise.

  1. MISCONCEPTION: Cold Climate Means Cold Home

 TRUTH: One of the biggest misconceptions about heat pumps is that they only work in more temperate climates — not true. Most efficient heat pumps, like Trane systems with their Climatuff™ Variable Speed Compressor, can handle temperatures as low as 0 degrees Fahrenheit for average-sized homes.

  1. MISCONCEPTION: Their Lifespan is Limited 

TRUTH: Rumor is that heat pumps burn out quicker because they run year-round. The reality is that as long as your heat pump is properly maintained, high-quality models will last at least 15-20 years.

Why isn’t my heat working? Heating problems answered

Why isn’t my heat working? Heating problems answered

Prepare for cooler weather with answers to the most common heating system questions

Fall is finally here. A time for pumpkin spice everything, festivals and crisp days and cool nights. Fall is also the first time most of us turn our heat on. What should you do if it doesn’t work? We’ve got troubleshooting tips for this and more common heating questions. Mom and son keeping warm under a blanket near a furnace

Shutterstock Photo By Lens Candy

Why isn’t my heat working?

ANSWER: The circuit breaker might have been tripped. Try resetting it.

ANSWER: Your thermostat may not be calibrated properly or set too low. Make sure your thermostat is set to heat. Try setting the temperature 2 to 4 degrees above room temperature.

ANSWER: Clean or replace your filters. Whether you have a gas or oil furnace or a heat pump, filters need to be routinely cleaned or replaced. You can use the owner’s manual to find where the air and oil filters are located in your unit.

ANSWER: The pilot light may be out or the gas turned off. If you have a gas furnace, make sure the gas line is switched on. If the main gas line is turned off, you’ll need to have your local gas company check. If you have an older gas furnace (before 1990), one of the first things to check is your pilot light. Your owner’s manual will feature detailed instructions on re-lighting the pilot. Contact your local Trane Comfort Specialist™ if you’re unsure. 

Why is it hot upstairs and cold downstairs?

ANSWER: Heat is escaping. Create climate zones to heat the rooms you want. The DIY way to do this is to close a few (not all) vents on the second floor. This forces your heating system to direct more air downstairs. Take this concept to the next level by having an HVAC professional install a climate zone system, like the Trane ComfortLink™ II Zoning System. In this system, heated or cooled air is directed where it’s needed most.

ANSWER: Your insulation and weather strips need to be replaced. As you know, heat rises and cold air collects on the ground level. So any cold air that enters through drafty doors and windows is going to be felt most downstairs. It’s a simple fix that can make a noticeable difference.

Why is the air flow so low?

ANSWER: Clean or replace your filters. Over time, dust and dirt will accumulate on the filter screen. There could also be a blockage in your air ducts. If this is the case, you’ll need your local Trane Comfort Specialist™ to inspect the ductwork.

Why is my utility bill so high?

ANSWER: Your system is running too much. If you have your thermostat set to a temperature drastically warmer than the outside temperature, your system has to work harder to maintain the temperature. This can result in a higher-than-normal utility bill. Try adjusting your thermostat to a more moderate temperature.

ANSWER: Your rates may have been raised. Your utility company might have raised their rates. Contact your utility company and compare the rates on your current bill with those from previous months.

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