Difficulty Removing Furnace Cover

[Willhound]

A previous ham fisted tech or brain dead owner has sealed all around the furnace cover and intake exhaust tube cover on my Suburban furnace with a combination of silicone and acoustic seal. Don't know what they thought they were going to accomplish besides me not being able to remove the covers. I can get it moving but the even sealed the intake and exhaust tubes to the cover so that as I'm trying to carefully pull, the tubes are moving and I'm afraid of cracking or breaking them at the furnace. I need to get that cover off for an upcoming install of a 420 lb permanent propane tank and the tech needs to do an inspection and get pics of the approval and spec stickers on the out side of the furnace. Suggestions? I see a product called Silicone Buster online. Anybody used it?

[Willhound]

And to maybe answer my own question, I searched a few schematics on line and it appears that the exhaust tube at least is attached to the chrome cover and pulls out if the furnace? Is it the same for both intake and exhaust?

[Rbalsinger]

You do not have to worry about breaking anything on the furnace. The two pipes are steel and fit into sleeves on the chrome cover. They can be quite a wiggle job to get them off under normal conditions. You might bend the covers but that is a good excuse to replace them.

[Bob K4TAX]

Use a thin blade putty knife to push through the goo all around the edge.

Yeah, looks like someone invested in a lot of clear silicone. Bad choice. To glob it on top is not the way to make a clean silicone installation. Less is best.

Bob

[Willhound]

Thanks guys. Yeah, gobbed it on for sure. And not even needed. There's a foam seal on the back side of the cover. And I've had the same cover of on a previous TT, but couldn't remember that the tubes come out with the cover. But better safe than sorry. I'll clean all the gunk off best I can and maybe repaint the cover while I'm at it.

[jimmoore13]

Originally Posted by Rbalsinger

You do not have to worry about breaking anything on the furnace. The two pipes are steel and fit into sleeves on the chrome cover. They can be quite a wiggle job to get them off under normal conditions. You might bend the covers but that is a good excuse to replace them.

X-2.
These furnace exhausts are intended to be removed easily. The exhaust from the furnace slides into a slightly larger exhaust tube attached to that exterior faceplate. The two tubes...furnace exhaust and exhaust extension...are not clamped together.
When you remove the chrome escutcheon plate, the concentric tubes come apart fairly easily.

I serviced the sail switch on my furnace, and I discovered that the easiest way to reinstall the furnace was to remove the outside exhaust, position the furnace, and then replace the outside exhaust. Otherwise, hitting that target while working inside a tight cabinet space was very difficult.

So get out your putty knife and have at it. This would be my choice for the job...stiff and sharp. You might benefit from applying a bit of heat with a hair dryer or heat gun to soften the caulk/adhesives.

In my rig, the "gasket" material around the exhaust escutcheon plate is a kind of soft, silly-putty-like material that keeps rain out but doesn't harden...and can take a little bit of heat.

P.S. As for the combustion air intake, the connection is usually even less elaborate. In my furnace, I'm not sure if there is even a "sealed" connection between the furnace and the combustion air intake. Each setup is different. So try not to ruin your exterior exhaust/intake system. They all function similarly, but not all have precisely the same design.