Air handler filter slot difficult to navigate when replacing filter

[Vdawg]

My home has an air handler with a slot at the bottom for the filter:

However, the horizontal aluminum frame at the top of the box below it obstructs the filter when being removed or inserted. It *can* be done, but you have to bend the cardboard filter frame pretty badly and really push/pull forcefully to get the filter in or out. It seems this isn't the way it's designed to be, and that there should be clearance in front of the filter slot to simply slide the filter in/out. The resistance is not inside the air handler or at the front opening of the air handler, as the filter moves in/out easily for the first inch or two until it hits that horizontal aluminum rail at the front edge of the box supporting the air handler. The condensate drain assembly makes it difficult to lift the filter up and over that horizontal aluminum rail:

I would like to take a Dremel and cut a slot in the aluminum rail to allow the filter to slide straight in/out without having to mangle it:

I could easily air seal any opening in the box with foil tape after cutting it, but my concern is with the *support* the box may be providing to the air handler itself. I don't know what's inside the box (if anything) to hold up the air handler, or whether the external box and frame are merely to construct a plenum for return air to travel through and don't provide any support to the unit itself.

Does anyone in the know have an idea as to whether this box/frame is likely to be supporting the air handler or if cutting a slot in that rail would be detrimental/unsafe with regard to supporting the air handler unit?

Thanks!

 

[Breplum]

Numbskulls installed that whole thing.
No way to know where the support is without pulling the filter and viewing what you can, but viewing the pics, possibly the whole air handler has depressed the sheet metal top already, causing the difficulty from being sagged?
The bent sheet metal frame IS holding everything together.
Looks like it may need serious rethinking.

 

[Sponsor]

 

[GoingQuiet]

Can we see what the remainder of the return duct looks like that hooks up to that base box?

What external size is the fiberboard return duct?

Can you permanently yank the original filter and install a 4” or 5” thick filter housing off to the side?

 

[Vdawg]

Thanks!

The entire "base" box is 22.5" wide by 22.5" high by 46" deep. Here are some additional photos/angles...

From the front:

From the side... You can see the air return is *behind* the unit in a narrow alcove, so I don't think a different location for the air filter is possible in this case. Left side:

Right side:

It seems to me that if the width of the stand/box had matched the width of the air handler so the sides of the air handler were resting on/flush with the metal frame both on the sides AND a the front, it would work much better. From what I see, the air handler IS depressing the top of the box putting the bottom of the air handler lower than the front horizontal frame piece, causing the filter replacement issue. If the front of the air handler was aligned flush with the front of the box (i.e. resting on that front framing member), I imagine replacing the filter wouldn't be as much of an issue as it is currently.

So is this a major issue for a qualified HVAC technician to correct?

 

[Fitter30]

There should be a little play on the supply duct side you could cut aluminum tape on the return side raise the ahu enough to put a 2 pieces of angle iron the full width of the box where the angle is resting on the metal supports that make up the box that would take the weight off the duct then retape. I'm also surprised the condensate drain works without a trap being a draw through coil.

 

[Vdawg]

FWIW, here was my solution: I ultimately ended up cutting down the top half of the top horizontal crossbar on the return/stand to make room for the filter to be slid out from the bottom of the air handler. It was only attached to the rest of the front frame at the corners, and I left those intact. Between the two corners, that horizontal bar actually had nothing attached to it's underside. The foam insulating board that makes up the top of the box was actually about 1/4" - 1/2" below it (leaving a gap which caused the original filter removal problem).

However, I did shore up the front of the stand first by adding a piece of aluminum flat bar across the front (just below the original top horizontal bar) to ensure there would be no new racking of the box, even though I didn't completely remove the original top horizontal bar. Additionally, I added an aluminum angle bar "sistered" to the original horizontal bar to help strengthen it (in terms of vertical flexing) since I removed about 1/3 of its top half along the top edge, then I taped everything up with foil HVAC tape. Nothing felt any different in terms of stability of the return/stand while making the modification and it seems to be working well now, allowing the filter to easily be slid in/out for future replacements.