What, exactly, holds my Danby AC unit in place?

JamesK

I've searched but can't find the answers in the forum. Apologies if I missed it.

I try to be as gentle as possible with my 2018 Tab boondock but forest road vibrations caused the AC unit to force the wood frame out along with the screws that hold it in.  I'm confident I can fix it, but when looking at how it all goes together I don't understand what holds the AC in.

The wood frame around the AC doesn't look like it holds the unit in except to catch the metal feet at the bottom of the AC.  But before the feet come into contact with the frame they are free to slide forward and break thru the top of the plastic drip pan. 



Here's some additional views of the AC's feet as well as the inside of the area that the AC unit goes.  By any chance is the AC unit supposed to slide back far enough that the metal feet at the bottom of the AC fall behind that composite strip across the front of the pan?  Mine doesn't slide back far enough but if it is supposed to then I'll look into what is preventing it.

What am I missing here?  Thanks!

Grumpy_G

I hear you. My 2015 has a different brand but they are just simple window AC units. Even pushing in at the lower edge the unit doesn't hook into anything so I guess the wood frame is all that holds it in place. 

MuttonChops

Wish I had a reference picture to help explain . . . .
My Feb/March Build 2018 has a metal bar across the front edge that the A/C Feet must be lifted over so the 'feet' can rest on the side metal " L " rails.  There is no composite material support as seen in your installation.  The metal cross-bar-step stops the A/C from sliding.  While the picture frame wood trim just hides the gaps.

Okay, later pictures in this thread clarify it is the plywood cabinet opening - -  not a metal bar - - - that my A/C must be lifted over.  Never trust memory.

JamesK

@MuttonChops If you look at my bottom picture and pretend there is no composite (there is a metal cross bar below it), and the metal feet of the AC rest on the side metal "L" rails, I still don't see anything that prevents the AC from sliding forward until the feet collide with the white tub plastic and break them.

On yours is there something preventing the metal feet from moving forward? 

BrianZ

A picture saves a lot of words, so here's ours, viewed from inside, opening at left..


Note, lip at front is the side of the plastic drip pan, but it's backed by the thick plywood front which you can see is screwed to the welded aluminum box frame.  Also some kind of composite fiberboard supports/cushions/blocks(?) the bottom front edge of the unit.  I'd have to go play with ours to confirm what might be intended to prevent it from sliding out.
PS: OK, now a lot of words..
It looks to me like, since the composite board in front looks thicker & taller than the metal side rails, the metal feet may slide on the side rails, but would be stopped by the board (which is also screwed into the welded metal frame). 
I seem to recall that, when removing the unit, it must be lifted to slide it out, but after a short distance must then be lifted higher to slide it further.  If you look at my photo, I believe the first lift gets the feet over the board, then the second lift gets it over the plastic edge & out.  If it bounced only maybe a quarter inch, the foot may clear the board, then with another bounce it might even break right through the plastic, which appears may have already happened since the break lines up with the edge of the foot.

BrianZ

Also, I'm curious what the tow vehicle is, and if there might be too stiff of a suspension, which can apparently shake a small trailer apart.

Mickerly

JamesK, I have a January 2018 320CS. Mine looks exactly like yours to include the broken condensation tray on the trailing, inboard corner. Our Danbys are held in by imagination. As you go over bumps, it jumps around. It pops out the same corner every time. I'm running out of good plastic to glue. If you fill the space between the cabinet frame and the Danby with "window AC weather stripping", you will stop all the drafts and it won't move as much. Finding something to keep it from moving and busting through the condensation tray is on my list for this winter while in storage. I was thinking a board or Styrofoam block above the front of the unit to keep it from bouncing inside the cabinet may work.

I do have a surprise for the trailer this year. A Frigidaire AC with a thermostat and quieter fan.

BrianZ

I wonder if there might be a way to attach a small block of wood or other device inside the cabinet & above the unit that could swivel out of the way for removal, but would be above the unit to prevent it from jumping up.

JamesK

@BrianZ Thanks for the very good info. 

On my unit, the bottom metal feet on the AC unit rest on the composite cross member.  On yours, the composite member is lower than the plywood frame which keeps the feet of the AC from sliding forward.  In this below picture of mine you can see that the composite member is higher than the plywood so there is nothing to catch the feet.  

Brian, on yours do you know if the AC's feet also rest on the composite cross member or do they slide back far enough that they can drop down and rest on the side metal rails only?

On the tow vehicle question we use a 2021 Jeep Grand Cherokee.  It is the only one I've used to tow the tab so it is hard for me to compare its suspension to others.  But my sense is that the root issue for me is that forest roads have bumps here and there and that there is literally nothing keeping the AC from sliding out so far that the metal feet push against the frame which is not really designed to hold it in, thus causing the screws to strip.

@Mickerly, "held in by imagination" gave me a chuckle.

 

BrianZ

Good question, @JamesK, I  don't know, but I'll take a look when I get a chance.
Yeah, it looks like either a structural failure or poor build quality on your unit.

MuttonChops

Well now . . . this shows how the production shifts over time.
Someone at nüCamp changed the A/C cabinet design to allow the thicker plywood to form a stop for the A/C Unit {my memory of a metal bar (in earlier post) being in-accurate}.

So the OP, @JamesK , needs to find a way to duplicate the function if not actual materials of the later builds that include the thick plywood step to stop A/C movement.

BrianZ

I found another shot from the same day 4 yrs ago which shows a different perspective which I believe also shows the relative heights of the different structures at the front..

It looks to me that the height of the plywood at front could be a quarter inch above the composite board which is about a quarter inch above the metal side rail.  I'm not sure where the A/C foot rests or if it rests on any surface in the normal position, but either way, it appears to me from the photos that it could be blocked by the composite board, and if resting on that board, it might be blocked from sliding further out by the plywood board.  Without measurements, I can't  be sure, but that's how it looks to me from this photo.  The two boards might possibly be at the same level, hard to say from the photos.

JamesK

Thanks @BrianZ.  On mine the root issue is definitely that the composite crossmember is higher than the plywood frame and the AC feet rest on that composite member.  This means the AC is free to slide forward of the composite, break the plastic tray, slide forward of the plywood box, and push the frame out, stripping the screws.

I measured my unit and there is no way the AC metal feet could fit behind the composite crossmember so my speculation is that they added the composite in order to raise up the front of the AC for whatever reason.  On my particular unit something was built wrong.

My fix was to use a couple of shelving pins, hook them behind the composite, and allow the pin to stick up into the bottom of the AC metal feet.  I guess its elegance is its simplicity.  The weight of the AC holds the bracket in place and the bracket prevents the AC from sliding forward.  The third picture shows the bracket just before I allow the AC to sit all the way done on it.

So I used some needle nose pliers to work the pins into place, verified that the AC unit was secure, put the wood frame back over the AC, turned it on for final test, and.... my AC doesn't cool.  So sometime during the past my AC stopped working.  But at least it is secure  

I'll maybe contact NuCamp to get their insight on the purpose of the composite crossmember and why mine is so high.  I'm unsure if this affects anyone else.  I may be the only one with this weird construction.  But I'll add it to the thread on the off chance that the info provides insight in a future forum search.

Now to go look for a new AC.

BrianZ

Clever solution with the shelf pin, @JamesK!  Can you also screw the pin into the composite so it doesn't move?

I got a chance to take a peek into ours after removing the outer frame, and you are totally correct!  The foot sits on the composite board and the cabinet face opening is no taller, if not equal or lower in height than the composite.  So, it does appear that only the plastic tray sticking up inbetween keeps it from sliding out!

I'm shocked that it's so unsecured!  They could have at least used a piece of 1/2" or 3/4" aluminum angle bracing under the composite board for a sturdy lip.  This could still be added & screwed or riveted on top of the existing aluminum box framing/under the composite, thus protecting the plastic as well.  Not sure if the extra 1/16" thickness under one side of the unit would cause any issues.
I feel just plain lucky we have no damage, wow!

pthomas745

Here is a search for "AC drain" with just the images from the posts.  Most of them show that aluminum bar across the front of the compartment. One of the AC removal threads even shows how to lift the unit just a bit to get it over the bar.

https://www.google.com/search?sxsrf=ALiCzsZ3Vbf_sHgWya6HhdWazXy5vx_q1Q:1657910355419&source=univ&tbm=isch&q=ac+drain+site:tab-rv.vanillacommunity.com&client=firefox-b-1-d&fir=JIgw7r7kCwCggM%2CXOQV7VIjxdvf8M%2C_%3B56wYrlFqg5ws9M%2Cemw6hVJHrSu-hM%2C_%3BKaZgENVdlOkJAM%2Cemw6hVJHrSu-hM%2C_%3BnUXZ_psRRQiboM%2CqB3_adJ1XaHZoM%2C_%3B1B3rSHExE19cOM%2CXOQV7VIjxdvf8M%2C_%3BZefaSLhp3XHbtM%2C3XqWP_DyqK0SGM%2C_%3Bk4lFBKoXb70SJM%2CPH5DG9EkF1K4EM%2C_%3BRZo24Am8C9RwEM%2CKAjpaxbx61Q9xM%2C_%3B6m9kk3hLJynQnM%2C3XqWP_DyqK0SGM%2C_%3BONAie4MeZin-nM%2C5Yu_sJpN7QMsdM%2C_&usg=AI4_-kTUDU-BYwXCjcn9LGlwXLSJG4j11w&sa=X&ved=2ahUKEwjZhLeuxfv4AhUUD0QIHZS4BKMQjJkEegQIBhAC&biw=1920&bih=1088&dpr=1#imgrc=LT7WA2pT3SFNTM

BrianZ

pthomas745 said:

Here is a search for "AC drain" with just the images from the posts.  Most of them show that aluminum bar across the front of the compartment.
..

What you're seeing in those T@B320 window unit photos is not aluminum, but the white plastic lip of the drain pan in the bottom of the cabinet that sticks up higher than the wood.  There is aluminum framing behind & below the opening in the wood cabinet, but none that would prevent the unit from sliding out, just the plastic lip.

Slackers

What @BrianZ has observed is true with our '19 CSS.  This may explain why the screws holding the AC's wooden trim are so long.

BrianZ

Even if one could reinforce the strength of the cover frame, this would not protect the plastic lip from breaking, right?
  
So, I'm considering adding a wood block of the same thickness as the plywood cabinet & same height as the plastic lip to the width of the opening.  It could be screwed [& glued?] into the existing plywood to prevent the plastic from getting broken, and it would block the unit from sliding out or into the outer frame.  Will have to look & make sure there is enough depth to the plywood to support screws. 

Another option might be to add an aluminum L-brace under the composite piece that would stick up between it & the plastic lip. It might not be possible to weld it because of the plastic right next to it, but screws might work through the composite and L-brace & into the aluminum square tube frame.

JamesK

BrianZ said:

Can you also screw the pin into the composite so it doesn't move?

@BrianZ, That's a good idea.  I suspect there isn't too much backward force on the screw (toward wall) that would pull it out and it would make placing the unit on the pins much easier.

I haven't looked into this any more as I've had to put my Danby on the bench to try and repair it (no luck, sadly).  My current thoughts are this: I think if you took out the composite the issue would go away as the metal feet would be stopped by the plywood.  But I assume the composite is there for a reason, perhaps to raise up the front of the AC for drainage.  My thinking is to take out the composite and cut off lengths that are as wide as the metal feet or perhaps a bit wider.  Then bolt these composite pieces onto the metal feet of the AC (they have holes already).  This would still raise up the AC but now the feet/composite would be stopped by the plywood.  I'd probably counter-sink the bolts so the bottom of the composite is flush.

The other thing I'm thinking is to do this with a hard'ish rubber material so that the metal feet rest on something that would give the AC a little shock isolation.  Not sure if that is a valuable effort.