Choosing the Best Filter for Heating and Air Conditioning Systems
Dust gets everywhere, including in our homes where it can set off allergies in sensitive persons. Dust also gets into heating and air conditioning systems and over time not only reduces its efficiency, but can damage the system. With the proper choice of filter, the HVAC system can function as an air filtration system making your home a more healthful one.
By providing regular maintenance and changing the filters often we can keep the system clean and trouble free. A clean system operates at optimal efficiency, saving money on energy costs and keeping our homes comfortable. You should never run the heating and air conditioning system without a filter. Let’s take a look at the most commonly used air filters:
Fiberglass filters, often called ‘blues’, keep out the larger dirt and debris that can cause damage to your system. They won’t do anything for air quality and must be replaced every month or more often if your environment is especially dusty. At $1 or so each they are definitely affordable.
Pleated filters provide a larger surface area and last longer between changes (usually every three months). If you tend to forget to change the filter, these are a better choice than ‘blues’. They capture smaller dust particles than ‘blues’ helping to keep your system cleaner. Though they last longer, all filters should be checked every month as increased dust can necessitate an early change of the filter.
If a family member suffers from asthma, allergies or respiratory disease, or if you have a pet or smoker in the house, an electrostatic or High Efficiency Particulate Air (HEPA) filter is recommended. HEPA filters are 99.7% effective in removing airborne particulates 0.03 microns or above in size through the use of diffusion filter. A pre-filter is required to capture large particles which would otherwise block the filters air flow. HEPAS magnetically attract particulates such as dust, mold and pollen. When used in conjunction with an air purifier and an immaculately clean house the best environment possible is provided for those with respiratory problems. There are HEPA filters available that will even capture viruses and bacteria ‘zapping’ them with ultraviolet light. For this reason, when cleaning HEPA filters wear gloves and wash hands afterwards. The cost of HEPA filters is greater but they can last up to a year, some manufacturers claim their HEPA product can last 3-5 years. Health experts advise using HEPA filters in conjunction with an air purifier to prevent overwhelming the HEPA system.
High humidity of 90% and above can have adverse effects upon HEPA filters, many manufacturers recommend turning the filtration system off when humidity is high.
Many filters carry a minimum efficiency reporting value (MERV rating), which gives an indication of their effectiveness. In general, those with the higher rating are more effective. Fiberglass filters generally have a MERV rating of 4, while pleated filters generally have a MERV rating of 6. Electrostatic filters have MERV ratings of 8 to 12 with 12 ratings being the top of the line. HEPA filters don’t generally bear a MERV rating as they exceed the standards.
It is easy to forget to change filters which can lead to clogging, and overheating which shuts down the burner in a furnace. Eventually the limit switch fails and the furnace then fails to fire up at all. The service call and a new limit switch are going to cost you considerably more than a new filter would have. Mark the day to change it on your calendar.
You should also keep a check on your filter as dust conditions may vary affecting when it needs to be changed. If you prefer not to take chances there is an air filter gauge available by General for about $15. It measures the airflow between the furnace and the filter through a small hose. With this gauge, various filters though new, may register as ‘dirty’. This may be due a particular filter type reducing air flow to the system which can cause overheating. It is important to adhere to the manufacturer’s recommendation of filter type with your HVAC system to prevent dangerous overheating. If you are unsure, contact the manufacturer or talk to your HVAC technician.
Some systems use washable and reusable filters. These also require routine cleaning to prevent breakdowns and increased energy usage. Follow the manufacturer’s recommendation for cleaning to prevent damage them.
Properly maintained your HVAC system should last you 10-11 years. It is an investment in your health and comfort. With regular filter changes and bi-annual maintenance from your HVAC technician you’ll get the most from your product for many years to come.
Cypress Heating and Air Conditioning are your dedicated professionals for all of your heating and air conditioning needs in Katy, TX.
Our certified HVAC technicians are available 24 hours a day, 7 days a week in order to be there when you need us most for furnace or air conditioning repair or replacement in Katy, TX. Service contracts are available for homeowners and businesses alike. Give us a call, and let us show you the Cypress difference.