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Steve P

I have a late 70's gas furnace/ AC unit. I have been using high end ($18) furnace filters but people recommend using a cheaper one because the high end tends to make the furnace work harder. Any thoughts? Thanks

Re: Filters

High priced ones do cause a little more load on the blower but they filter better. Pay for the filters or for having your furnace and A coil cleaned.

Steve P
Re: Filters

Thanks for the advice. It's winter check up time so I'll get the coils cleaned and the blower looked at also.

Re: Filters

MERV ratings are used to rate the ability of a filter to remove dust from the air as it passes through the filter. MERV is a standard used to measure the overall efficiency of a filter. Higher MERV ratings mean fewer dust particles and other airborne contaminants pass through the filter.

MERV ratings range from 1 - 16 and measurements are in microns. Some of the common particles related to MERV ratings are pet dander, insecticide dust, smog, dust, viruses, wood, tobacco smoke, spores, bacteria and pollen.

Some of the most common filters found in residential use only have a MERVrating of 1 to 4. These are typically disposable panel type filters and do not do a good job of filtering the air because they will not stop particles smaller than 10 microns.

Merv 5 to 8 rated filters are a better choice. These filters will collect particles as small as 3 microns and are a good choice for home owners.

Filters with a MERV 9 to 12 will stop particles in the 1 to 3 micron range. These filters are a great choice for home owners who want the best dust control possible. When using filters with Merv 9 ratings and above it is important to clean or replace them when recommended by the manufacturer because they will have a negative effect on air flow when they become dirty. This can lead to performance problems and decreased operating efficiency.

I use an electrostaic reusable filter with a MERV of 9 and clean it monthly otherwise the furnace performance does decrease.

Hopefully this helps. :)

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