Which Furnace Air FIlter?

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My furnace takes a 16x25x1 filter. The furnace technicians are on me about just using the cheap fiberglass ones. How efficient should I go without compromising
the longevity of my blower motor and heat exchanger?
 
I have the same filter dimensions and I tried a higher merv filter (12) that filtered out allergens as I was experimenting with cold/flu reduction during the winter months. For my application, that there is a such thing as selecting too high a merv rating as there was a noticeable reduction in airflow, resulting in longer heating times and more costly bills. Also, it didn't reduce the number of colds/flu.

I went back to a merv 8 and heating times were back to normal and the amount of dust was pretty much the same as the merv 12.



**What did reduce the number of colds/flu was to change the heating range from 19C (night) and 21C (day) to 19.5C (night) and 21C (day).
 
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Not knowing what my system can handle (builder installed 10+ years ago) I've run Merv 8 and called it a day. No filtration issues that I can tell.
 
So it seems going up to a MERV 8 would be a good compromise...
 
I use the midgrade ones more than the blue fiberglass, but not smoke or hepa level.

I think they were "Allergen+" about the equivelent of the 7 or 8 level honeywell at home depot.

I picked up 24 filters for $88 still going 5 years later on them. When not clearanced they were around $12-14 each.

I want more than a rock catcher.. something that will do a decent job on dust.. since I dont have carpet.. but I dont want the headaches that come with hepa/very restrictive filters.
 
I've been using Merv 11 filters for decades in both air handlers. We just replaced one of the '87 vintage Trane air handlers-it never had any issues at all and only needed normal maintenance over it's 30+ years. The only reason it was replaced was because we're updating all of the HVAC equipment, and that unit and its heat pump are the first to be replaced.
 
I've talked to several HVAC individuals and they all said the same thing. If you system is old and not brand new go with the inexpensive fiberglass "tumble weed" catchers. They work just fine.

If you use a more restrictive filter on an old system with old duct work then it will start to pull air from all the bad joints in the duct work which you don't want to it to do.
 
Got an electronic air filter on my HVAC installed in 1990 but don't think it's been working for at least 10 years now and haven't washed the grids in that time either. System seem to work fine none the less.
 
+1 on the 3M Filters. I buy a 4 pack of the different rated filters, two green, one red and one purple from Lowe's when they go on sale for $20.
 
I use the lowest priced Rheem pleated. You can find them at Home Depot. Look for Rheem FPR4. The higher you go on the MERV rating, the more restrictive the filter. The Home Depot site specs it as a MERV 6.
 
At least buy a "pleated" filter not the fiberglass.

As far as efficiency, it depends on the air quality you have in your area and your desired air quality.
Also, if there is somebody smoking, the filter will need to be change more often and you need higher efficiency filter.
 
I'm surprised the tech gave you grief. The few times I've had dealings with the HVAC people and from what I've read online, they tend to stick with the cheap fiberglass filters and justify that by saying the filter is just there to keep large debris out of the blower. If you want air purification, buy a separate purifier/filter.

That having been said, when I've upgraded, I've used something in the MERV 7-8 range.
 
My HVAC guy says cheaper is better and change on a regular basis. Too much restriction isn't good.
 
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