Furnace Filters

[Trice]

It's been awhile since I looked this up but I recall finding information that was all over the place. So I started asking the HVAC guys what to do when they'd show up for maintenance, and their answers were pretty consistent. They all said there's no need to spend a lot on high-end filters. The higher the MERV, the harder it makes your furnace work, which can shorten its life. And changing it every 3 months or so is fine, having some accumulation on the filter helps it filter more stuff out, up to a point.

I buy a giant box of a dozen(?) Dupont Basic filters from Menard's for ~$35-40.

 

[alarson]

I don' think it damages it but reduces longevity. I just do what my hvac guy says to do. He knows the brand and also warranties it.

Yeah, more strain on the furnace is the thought. That's why if you get a higher-end filter you want to be replacing more often as less air flows through as they filter out more particulates

I have my thermostat set to remind me to replace based on runtime hours instead of just months.

The biggest difference i've noted vs cheaper filters is when wildfire smoke finds its way here. The smoke really gets to my eyes, and I notice a big improvement with the better filters.

 

[Clonehomer]

We also use the cheap ones. But as I am forgetful, I buy a 12 pack at the beginning of furnace season and mark the month on each one so I know whether I’ve changed it or it needs to be changed.

 

[FarminCy]

Get an air purifier if you want clean air. The filters are only supposed to stop the big stuff. As others have said, the higher MERV value restricts and damages furnaces.

Sons allergist told us to focus on air purifiers, clean bedding, and frequent vacuuming. Told us the super fine filters can’t remotely replace what a good air purifier will do.

 

[Clonedogg]

The 4-5" filters are more expensive but you're only supposed to change them once a year.

 

[BoxsterCy]

With no wife to tell me to check the furnace I guess CF is my furnace patrol. Just went down and changed mine.

Time to order some more off the interweb, usually get a three pack so I have filters when I think to change them. The 20x25x5 filters I need don't last long since I generally have my fan run 24/7 to keep the temp balanced throughout the house (also have two rooms with vaulted ceilings so it helps to keep the air moving.

It's annoying that they use different numbers, see some still with MERV but others with only FPR rating.

 

[wxman1]

Made sure to change mine before the last extreme heat stretch.

 

[houjix]

The 4-5" filters are more expensive but you're only supposed to change them once a year.

Depends on the style, but I change mine at 6 month intervals max.

 

[TitanClone]

I just had Amazon deliver them once a month at my last place. Delivery day was replacement day. I doubt there's any difference if you replace frequently.

 

[DSMCy]

The 4-5" filters are more expensive but you're only supposed to change them once a year.

Got a new furnace last year that uses the 5" ones: 16x25x5

Didn't realize these come in different "actual" sizes, so of course the one I got at Lowes was too big.

 

[Sousaclone]

I just had Amazon deliver them once a month at my last place. Delivery day was replacement day. I doubt there's any difference if you replace frequently.

That's actually a really good idea. I should go look at mine. Changed it this past spring, but I don't have central AC so my HVAC system hasn't run since probably april.

My apartment complex right out of college always just a kept a couple of boxes in the office and when people went in to drop off rent checks they'd give you one to swap out.

 

[BigTurk]

Sons allergist told us to focus on air purifiers, clean bedding, and frequent vacuuming. Told us the super fine filters can’t remotely replace what a good air purifier will do.

and you can plugger an air purifier using expensive pleated filters and a box fan. Just tape the filter to the back, or front, of the box fan, and turn it on.

 

[NATEizKING]

Definitely depends on your furnace, old furnaces aren't made for the more expensive restrictive ones. Just like old washing machines shouldn't use HE detergent. My furnace is old enough (pre-2010) that I should only be using the cheapest and changing monthly.

 

[ruxCYtable]

I use the cheap ones and replace when my Nest thermostat says it's time, usually about twice a year.

 

[mywayorcyway]

We just bought a new house with a Bosch HVAC. Didn't even know they made them, and I didn't know what used 20x25x5 filters I saw in the stores. Now I do. Even the cheap ones aren't cheap!

 

[tim_redd]

Anyone tried the reusable filters?

 

[SEIOWA CLONE]

We use the 20x25x1 filters, the 1200 MARV rated and switch them out every two months. Last year we also purchased a couple of the Blue whole house are purifiers, one for the main living area and one for our bedroom where we also have the washing and dryer in a closet. The Blue purifiers are great, really clean out the dog hair from our 2 Goldens. We change the filter in those about every 6 to 7 months.

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www.blueair.com

 

[BoxsterCy]

We just bought a new house with a Bosch HVAC. Didn't even know they made them, and I didn't know what used 20x25x5 filters I saw in the stores. Now I do. Even the cheap ones aren't cheap!

Just order these from Home Depot. Did a lot of looking and these Honeywell ones seemed to be a good buy at around $25 (two-pack for $50) each versus $36 for what they have on the self in the store. These are Merv 10s. Free delivery.

20 x 25 x 5 Pleated Furnace Air Filter FPR 8, MERV 10 (2-Pack)

 

[mywayorcyway]

Just order these from Home Depot. Did a lot of looking and these Honeywell ones seemed to be a good buy at around $25 (two-pack for $50) each versus $36 for what they have on the self in the store. These are Merv 10s. Free delivery.

20 x 25 x 5 Pleated Furnace Air Filter FPR 8, MERV 10 (2-Pack)

I just received a set of 4 for $95 from an online filter store, similar filter. I set the reminder for six months out, we'll see what it looks like then.

 

[somecyguy]

We just bought a new house with a Bosch HVAC. Didn't even know they made them, and I didn't know what used 20x25x5 filters I saw in the stores. Now I do. Even the cheap ones aren't cheap!

I have a 5" filter as well. $25 for a filter isn't cheap! I have found that 4" ones work as well, just an FYI