Choosing The Right Air Filter For Your London Home

February 06, 2015

Trying to select the right air filter for your London home can be a daunting experience. Which brand is best? Does the price reflect the quality? These are just a few of the questions that make purchasing air filters for your home mind-boggling. Let Roy Inch & Sons Service Experts Heating & Air Conditioning try to help you de-mystify the air filter dilemma.

Here’s an easy way to determine how efficient your existing filter is (NOTE: To avoid a big mess, we highly recommend conducting this test outside or over a protected surface): Hold the filter horizontally, then with standard table salt, start pouring the salt through the filter then see the quantity that comes out the other side. If some or all the salt falls through the filter, then you know that the filter will let dust pass through as well. You should probably upgrade your filter to higher quality filter that is more efficient.

There are 3 primary considerations when choosing a household air filter; Size, Material and MERV rating.

1) Filter Size

Purchasing a properly sized air filter for your London home is important. Simply look at the label of your existing filter to see the height by width and thickness, or just measure it yourself. The majority of home air filters are 1” thick, but there are a number of standard width and height dimensions, and some systems have thicker filters.

2) Material & MERV Rating

Filter efficiencies are given a number from 1-16 called the MERV rating. MERV stands for Minimum Efficiency Reporting Value. This number tells the user, under the least efficient conditions, how well the filter is designed to capture contaminants.

To explain MERV ratings more impactfully, these are some common MERV ratings and how they correspond to efficiencies. This is only a guide, so don’t forget to read the filter manufacturers’ information when purchasing specific filters.

Rating Average Filtration Efficiency

MERV 1-4 60-80%
Fiberglass, Disposable Panel, Washable metal/synthetic, self-charging (Passive)

MERV 5-8 80-95%
Pleated, Media panel, Cube

MERV 9-12 >95%
Extended pleated

MERV 13-16 >98%
Electronic

Be Careful About High MERV Ratings

While a higher MERV number may ensure better filtration efficiency, it is extremely important to understand that too high a MERV filter may also cost you more to operate your furnace and AC system. The higher the MERV, the more restricted the air may flow through the system, and the harder the system may need to work. Your goal is to get the right balance between air flow, air filtration level and energy efficiency.

Think about it this way, the most efficient ‘filter’ would equivalent to a piece of plywood that stops ALL contaminants and all the air from getting into your London home. That's definitely the “best” air filtration
, but would also be like living in a box.

The default choice for most systems would be a MERV 6-8. A higher MERV filter should be used based upon the advice of your Roy Inch & Sons Service Experts Heating & Air Conditioning technician to verify your system has the capability of moving the suitable quantity of air through higher efficiency filters. You generally do not want to lose energy-efficiency for filter efficiency; you want a balance of the two. However, if your family suffers from allergies or respiratory problems and a high MERV rated filter is required, consider a
whole-home air filtration solution that will meet your energy and filter efficiency needs.

Filtration has changed considerably over the past ten years. Early on, home air filters were used in the furnace or air handler only to protect the comfort equipment itself. Today it’s a whole new ballgame. London area homeowners expect their air filter to save kids from a wide variety of harmful pollutants, dust mites, and even prevent the need for dusting. Dare to dream!