Inside A/C cover falls to floor. Nothing in ceiling to screw into.

[Janet and Todd]

On the way home with our new (to us) coach, the interior A/C cover fell to the floor. Examination revealed that the screws were attached to foam insulation only. I ran a bamboo skewer into each hole until it stopped and measured it. it went in 5 inches and hit the underside of the fiberglass roof. The dealer replaced the front A/C gasket before we took delivery and discovered that the air horn hose had been routed across the A/C gasket. I'm not sure what, if anything can be done to create a solid attachment to screw into above the headliner. We have the vinyl spongy ceiling, not the fuzzy one. Any thoughts? I'm not comfortable removing the plenum, plus it looks like quite a bit of hard spray in foam insulation was used to reassemble the unit after replacing the gasket.

[EngineerMike]

The ceiling foam could be useful if you gain enough contact area. Drill the screw holes out to 1/2" diameter for depth of~3". Glue in a 3"piece of 1/2" dowel. Mark & predrill screw holes & voila.
Gorilla glue or epoxy would be my choices.

[Janet and Todd]

Now *that's* clever. What an elegant solution! Thank you, Mike. As the kids would say: "#impressed".

[EDALLSAILS]

Duct tape always works in a crisis situation. Add a little Velcro and it will stay put. Wife doesn't allow me to use any power tools as she is afraid I'll hurt myself. safe travels... ed

[BFlinn181]

I'd think a small piece of aluminum, or even wood could be put into a pocket carved out of the foam, then a can of insulation foam could be used to lock it in place, holes drilled, and the cover secured. If there's nothing to limit it, a piece long enough to cover a side, from corner to corner could be more easily and firmly foamed in place. Spray foam is incredibly sticky when wet, but once cured, you can carve the over-expansion away. Use the type that has limited expansion properties.
Is there a second A/C? How is that cover fastened in place? I'm curious how it was secured in the first place. Why and what mods were done to leave the cover so poorly fastened?

[Janet and Todd]

Yeah, I'm curious too but not curious enough to remove the rear one to find out. I think I'll leave well enough alone until something happens to cause me to remove it. Perhaps there was luaun up front but the leak caused it to rot away? No staining on the headliner however. Good responses here. Please keep thinking...

[Jim A]

Fortunately it has been years since I took my inside cover off of the A/C, but I believe the screws originally went into a thin sheet of plywood that is part of the foam sandwich that created the ceiling. It is probably only 1/4" plywood and easy to strip out.

If there is plywood that is stripped out, you might try using a speed nut of it is close to the edge, which it should be. Like this:

Fold over clips, Speed nuts, Bolt retainers. Regular or Bulk Packaging

ACE would have them if that would work.

[EngineerMike]

Mine seat into a small strip of sheet metal angled at 45degrees at each corner. Not sure how that strip is anchored.

[wa8yxm]

The inside cover is SUPPOSED to screw into the ceiling unit (The part that goes through the roof) not to the motor home... Somebody screwed up (in this case literally since you drive the screw UP into the metal of the duct work).

[Basil Shannon]

WRV used Coleman AC units on the Apex (not Dometic) and a chillgrille that looks like this:
Coleman-Mach ChillGrille for Air Conditioner, Heat Ready, Lateral Ducts, White - Rv Products 8330E635 - Air Conditioner Accessories - Camping World

For whatever design reason, the grill is not connected to the sheet metal of the AC unit itself, but screwed into the thin luan ceiling. I recall 75598 having plastic drywall anchors as some kind of fix for the screws pulling out. (Probably @ Camp WRV service).

Other Apex owners experience/observations?

[Janet and Todd]

I guess there is luaun up there but I can't tell how far it extends beyond the plenum. I sure don't feel any near the screw holes for the panel.

[Janet and Todd]

Here are some other views of the area in question. Have I assembled the metal plate with weatherstripping correctly in the cover?

[Janet and Todd]

Okay, holes drilled, dowels cut, monkey glued and inserted. I'll give it a few days to cure then mount the cover.

[EngineerMike]

Oh man. I hope that works.