4" HVAC filter in 5" housing

[rjacobs]

I have 2 HVAC air handlers that take 20x20x5 filters...

Bought my last ones at Home Depot(honeywell brand). They dont carry them anymore. The honeywell site is useless for looking up filters. I checked the Filtrete website and they dont list a 20x20x5 filter(its greyed out) either...

I was going to order some Nordic Pure filters from Amazon, but they are listed as like 19.5x19.5x4.25 or something like that...and lots of reports they dont seal around the edges due to this.

I can get Honeywell 20x20x4 filters at Home Depot. These measure out at 20x19.75x4.5(according to homedepot.com)...

Any issues with running a 4"(really 4.5") filter in a 5" housing?

I called a few supply houses around me and they wont sell to a consumer. I gotta have an account and to setup an account I need an HVAC license... so im stuck with either what Home Depot sells or ordering online(which seems I am not really even sure what I would be receiving and no guarantee of not having massive shipping damage)...

 

[Onator]

There’s got to be someone in the Dallas area that will sell you that size. If you’re unable to track them down anywhere else or don’t want to order them online (probably the cheapest route) then you can try these guys>

https://www.deyparts.com/product/inv_24002103

According to their site, they have 20x20x5’s in stock. They do sell to retail customers. You can also create an account for yourself (don’t have to be lisenced or anything)and get a discount.

I go to Dey when I need something right away or want OEM parts - otherwise its always cheaper online...

 

[snorky18]

I order my 20x25x4 filters from iallergy.com

I don't see any reason the thickness matters between 4" vs 5" or anywhere in between.

If you were really worried about it you could put some sort of foam or weatherstripping to fill the remainder of the gap up to 5" thick, but I've never had a problem using a 4" nominal thickness filter in a housing that will probably take up to 4.5" thick or so.

One caution - I thought I found a great deal on filters at zoro, but they were metric equivalents, and they never quite fit right. My bad for not paying more attention when I ordered them.

 

[rjacobs]

I order my 20x25x4 filters from iallergy.com

I don't see any reason the thickness matters between 4" vs 5" or anywhere in between.

If you were really worried about it you could put some sort of foam or weatherstripping to fill the remainder of the gap up to 5" thick, but I've never had a problem using a 4" nominal thickness filter in a housing that will probably take up to 4.5" thick or so.

One caution - I thought I found a great deal on filters at zoro, but they were metric equivalents, and they never quite fit right. My bad for not paying more attention when I ordered them.

I guess my only worry is them shifting when the blower kicks on and possible causing them to bend. I know the filters these days are built like garbage...

And your "metric equivalent" I think is the issue with the Nordic filters on Amazon. The metric doesnt translate to imperial very well on some things.



I will be going to buy the 20x20x4 honeywell's and see how they do. I wont peel the plastic until I check them for fit.

 

[rjacobs]

There’s got to be someone in the Dallas area that will sell you that size. If you’re unable to track them down anywhere else or don’t want to order them online (probably the cheapest route) then you can try these guys>

https://www.deyparts.com/product/inv_24002103

According to their site, they have 20x20x5’s in stock. They do sell to retail customers. You can also create an account for yourself (don’t have to be lisenced or anything)and get a discount.

I go to Dey when I need something right away or want OEM parts - otherwise its always cheaper online...

If the 20x20x4's at Home Depot dont work, I will run up there and check them out. Thanks.

 

[LS6 Tommy]

You might lose a teeeeeeny bit of efficiency, but other than that there's no reason not to run the 4". You can always stick a wood or metal shim in the bottom track to locate the filter up against the rack if your worried about it moving or bypassing.

Tommy

 

[rkevins]

you may need to shim on the outside to keep them tight when the blower is off

 

[rjacobs]

I got the 4"... they were overall way loose in the housing. I think because the dimensions are not 20x20, they are like 19x19... and the 4" dimension that is called 4.5", no its not either... Just didnt feel comfortable leaving a filter in there that "rattled around" so to speak. The flanges that are in the units to hold the filters in place are only like 1" tall... it felt like the filter was going to get sucked in and be tilted because it wasnt captured by the top flange at all.

Hot dog down a hallway...

I returned them...

I will be going to check out the place that Onator suggested to get some 5" thick filters...that hopefully have a true 20x20 dimension.

 

[Done That]

Supply House online has the Trion Air Bear which are well made and run close to true dims. Have the foam strips too on top and bottom for sealing.
I'd ask, usually a case is three and much less likely for shipping damage.
Just another option. I use 4" filters in my 5" filter box but it was designed with a removeable rail to accept either size.

 

[yeldogt]

Is this an actual cabinet ? or something that the installers built.

If a Cabinet w/ manufacturer name someone has to make them.

The 4" are the more common size and I buy them from Amazon in whatever is the cheapest way .... often the 2 pack.

 

[SethB]

Been getting mine from https://www.filters-now.com/ for 15+ years. Skuttle housing 20x20x5 MERV 13 now.

 

[rjacobs]

Supply House online has the Trion Air Bear which are well made and run close to true dims. Have the foam strips too on top and bottom for sealing.
I'd ask, usually a case is three and much less likely for shipping damage.
Just another option. I use 4" filters in my 5" filter box but it was designed with a removeable rail to accept either size.

Ill check out supply house. I dont mind ordering as it seems thats going to be my option.

Is this an actual cabinet ? or something that the installers built.

If a Cabinet w/ manufacturer name someone has to make them.

It wasnt built by the installer, its manufactured for sure. The outside units are Goodman so I assume the inside air handlers are as well, but I dont recall seeing a name on them, but I didnt look to closely... although to be fair the filter housing is a seperate piece attached to the air handler on one side and the return/makeup air duct on the other... so the actual filter housing may or may not(probably not) made by the same manufacturer as the air handler.

Been getting mine from https://www.filters-now.com/ for 15+ years. Skuttle housing 20x20x5 MERV 13 now.

Ill check them out.




Thanks for all the places to look online... Like I said the first time I replaced them(in July, we moved in in June, wanted to get the 3-4 months ones out that had a lot of construction dust in them) I just bought them at Home Depot. Honeywell brand. But they dont carry that size anymore and supposedly not made. I dont mind ordering online now that I know that I cant get 5" locally.

 

[bonneyman]

You might lose a teeeeeeny bit of efficiency, but other than that there's no reason not to run the 4". You can always stick a wood or metal shim in the bottom track to locate the filter up against the rack if your worried about it moving or bypassing.

Tommy

I used to replace electronic filter cells with 4" pleats all the time, because the customer didn't want to shell out the $$$ to replace bad cells. The housing was there and installed - found out stock 4" pleats would slide right in. A little thinner and not as high efficiency, but operation was no problem.

 

[nadogail]

IMHO, Wooden Spacers are the classic remedy for this situation. Some would bend up metal spacers, but they would be expensive.