Well, that raises another problem - there is no access hole on the coil - in addition to the copper lines, there are 4 holes in the box - all of which are clustered together in the bottom right corner.
Each has a 1" PVC line coming out - 3 of which are capped, the 4th is the drain.
The coil’s box has Al tape (i.e. real duct tape - it is soft aluminum these days. Yes, I have some on hand) around the center and on the (vertical) corners.
I can feel a seam under the horizontal, and the verticals cover screw heads - it seems the entire front panel is to be pulled to access the coil - does that sound like a reasonable conclusion? Bending the copper lines nad moving the entire drain piping to get to the coil?
If I had a large hole punch, I’d drill a hole and make an access port - but the largest hole punch I ever had was 3 1/8 and I needed the money more than the punch years ago.
I’ll leave it to the reader to figure out what the 1/8" was about
In all likelihood, to access the coil, you probably pull the tape and remove the screws and a sheet metal cover should fall off (or dangle from the copper lines of they go through the cover). To clean the coil you or I would just reach in and clean them. It probably wouldn’t hurt to fit a piece of cardboard into the bottom so all the crap doesn’t fall into the heat exchange and blower down below.
If there’s a enough slack in the lineset, someone with some experience can slide it out, but it doesn’t disconnect (not easily anyways), so there’s not much advantage to Joe Homeowner trying to move the coil on his own and there’s A LOT of disadvantage.
I don’t think you’d want to try to clean through a 3 inch hole. You’d probably cut your arm. It’s going to require a lot of maneuvering. This is what’s inside of the plenum. And now that I go find a picture of one, it dawns on me that front and back may be sealed and maybe you do have to go in from the bottom and maybe you are supposed to slide it out a bit…sounds like a raindog question. Though there are sprays you can get. My experience with cleaning coils is more on the commercial side which give you a lot more access to both sides.
Also, I’d be really careful cutting into the sheet metal until you know what’s on the other side of it. If you cut to deep, it’ll get really expensive really fast.
The lineset and PVC pipes are smeared with an asphalt-type mastiic of some sort - the sheet metal will definitely not slide back along it.
The lineset comes from above and is loose for about 4’ - assuming the pipes are not connected to anything except the panel, the lines could be swung backwards - but I have no idea how to support the weight of the coils and keep it from dropping down - I suppose it could rest on top of the furnace - it forms a shelf there.
Unfortunately, the flue runs immediately in front of the coil and plenum. I"m guessing this is why the flue has a joint about 20" up - to allow the section connecting the furnace to the upper section to be removed for access to the coil.
So far today, the t’stat is behaving itself. May it knows it’s going to be replaced tomorrow.
