The air filter is an essential part of your HVAC system. Although many people refer to it as a furnace filter, it actually plays an important role for both your heating and air conditioning. Its main function is to trap dust and debris to ensure it cannot get inside the HVAC system and gunk up or damage the furnace and blower fan. It also helps to improve indoor air quality by filtering out allergens and contaminants. If you don’t replace the air filter regularly, it can cause numerous issues for both your heating and cooling systems.
When to Replace Your HVAC Air Filter
You should always make sure to replace your HVAC filter once every 90 days, at the very least, throughout the entire year. Since the filter affects both your heating and air conditioning, during the hottest and coldest times of the year when your HVAC system runs throughout most of the day, you will probably need to change the filter every four to six weeks.
You should also make sure to check the condition of the filter every week or two and replace it whenever it starts looking too dirty. A bit of dirt and dust on the filter usually isn’t an issue. However, if there is a thick layer of dust, lint and hair covering the surface of the filter, then it is definitely time to replace it.
When replacing the air filter, it is important that you put it in the correct way, as it will only work in one direction. Air flows into the ductwork and then through the filter into the furnace. If the filter is reversed, most of the particles will flow straight through it. Luckily, the filter always has an arrow that shows you which direction it should face, and this arrow should always be pointed at the furnace.
Disposable vs. Washable Air Filters
The majority of HVAC air filters are disposable and are simply thrown away whenever a new filter is needed. However, you can also opt to buy a washable filter instead. Generally speaking, washable filters tend to be quite a bit cheaper in the long run and also much more environmentally friendly. While they do tend to cost quite a bit more up front, washable filters usually last for at least 10 years and will definitely save you money compared to buying a new filter every few months.
All that being said, the majority of people still opt for disposable filters. The main reason is simply for convenience. If you always have a spare filter at the house, it will only take you a few minutes whenever you need to change it. If you use a washable filter, you’ll need to spend at least 10 to 15 minutes to fully wash and rinse it.
There is really no difference in terms of how the filters work or how effective they are. This means that it is mostly a matter of personal choice and depends on whether you’d prefer the convenience of disposable filters or you’d rather save a bit of money by using a washable filter.
What Happens if You Don’t Replace Your Air Filter?
Failing to replace your air filter regularly can lead to a whole host of issues that can drastically shorten the life span of your furnace, air conditioner and HVAC blower fan. If the filter is covered in dust and debris, it clogs so that very little air can flow through it. This puts a huge amount of strain on the blower motor since it has to work much harder to draw air through the filter and into the rest of the HVAC system.
The reduced airflow also limits the effectiveness of your heating system in the cold months and your AC during the summer. As a result, your system will need to run for a longer time to heat or cool your home to the desired temperature. This puts added strain on the HVAC system and increases the wear and tear on the units. This can eventually lead to more frequent repair needs and a shortened overall life span. The issue also means that your heating and cooling costs will be much higher.
A clogged air filter can create various other issues and can even seriously damage your furnace. If the airflow is restricted, the blower won’t be able to properly circulate air through the system. If not enough air is coming into the system, it leads to the heat building up inside the furnace instead of being circulated through the ductwork. Over time, this excess heat can cause the furnace’s heat exchanger to crack.
The heat exchanger is what transfers the heat inside the furnace to the colder air being drawn into it. As the furnace burns gas, the heat this creates raises the temperature of the heat exchanger. Cold air coming into the system flows over the heat exchanger, and the heat energy is then transferred to the air.
The heat exchanger essentially acts as a conduit between the hot gases inside the combustion chamber and the cold air. If the heat exchanger cracks, it can allow carbon monoxide and other harmful combustion gases to escape out of the chamber and seep out into the ductwork. The blower fan will then circulate these gases around the home, and this can lead to potentially fatal carbon monoxide poisoning and other serious health issues. This is yet another reason why it is essential that you replace your air filter regularly.
A clogged air filter can also cause your air conditioning to not work properly. If you attempt to run your air conditioning with a clogged filter, it will often lead to the evaporator coil inside your air handler developing ice and eventually freezing solid. When this happens, your AC won’t produce any cold air until you shut it off and wait for the coil to fully thaw.
This can be a serious issue that has the potential to burn up the motor in the outdoor AC condenser unit if you continue to try to use the AC when it is frozen. Should the condenser motor burn out, your only real option is to replace the entire AC unit.
When the filter is clogged, it prevents the blower from drawing enough hot air into the air handler. If there isn’t sufficient hot air flowing into the system and over the evaporator coil, the refrigerant inside the coil will remain much colder. As a result, the moisture that naturally condenses on the coil will quickly freeze instead of dripping down into the drain pan, and the coil will eventually freeze up.
Expert HVAC Services
At Gallagher's Plumbing, Heating and Air Conditioning, we offer a full range of heating and cooling services for residents in the Greater Sacramento area, and we also have locations in Los Molinos and Olivehurst. Our certified HVAC technicians install, repair and maintain furnaces, electric heat pumps, air conditioners, ductless mini-splits and hot water heaters. We also specialize in duct cleaning and install and service a variety of indoor air quality equipment. We offer a full range of residential plumbing services. Give Gallagher's Plumbing, Heating and Air Conditioning a call today if you have any questions about your furnace filter or need to schedule any heating or cooling service.