Levelling furnaces

[DaveP]

Had TSSA audit recently, no major issues, but inspector was not happy with S or D cleats being used to level/shim furnaces which I tend to agree with.  He indicated inspectors had been directed to pay attention to this issue.

Argument was that the S/D cleats can be easily dislodged, compress over time, rust and deteriorate, safety issue if someone caught a toe on it, and made for sheetmetal work, not leveling furnaces.  Small round metal discs that I have seen for leveling water heaters were mentioned as more acceptable.  Anybody seen these and know where to get them?  I see them often under heater legs, I think they used to come with tanks, but can't locate them anywhere. 

Anybody using/suggest anything else?

Going to a metal shop and getting a bunch of steel strips made of differing thicknesses was mentioned, using silicone/adhesive to hold them together if they are stacked.

We are not talking much of a gap, if the floors off alot then a patio slab is a much more appropriate method.

Thanks

[Admin]

The trick is to continue using cleats but place them under the furnace so they are no longer visible.  The argument that the cleats would rust is not really valid, because so can the bottom of the furnace.  The cleats I use are coated to prevent rust.  Using drive cleats should be okay because they wont compress very much at all.  I don't know of any place that sells those round discs that ship with some water heaters.

They enforce Clause 7.13.1,

7.13.1 - A central furnace shall be installed on
(a) a firm, level base;

Their main argument is that shimming the corners is not leaving a firm and level base, as the middle of the furnace is no longer "firm". 

If they were really concerned they would enforce the Building Code and adopt a Gas Code to secure all gas equipment to prevent overturning or displacement should an earthquake strike.  This is an OBC requirement in Ottawa and a lot of other cities, but not enforced by the TSSA or Enbridge.

[Attavior]

What are your thoughts on cement bricks being used?  In our area only allowed if the complete underside of the furnace is on top bricks completely and glued on place.

[Admin]

Yes, most inspectors want the blocks glued so they are "firm".  There are no problems installing furnaces on patio stones or blocks.  Some older furnaces weren't approved to be installed on combustible floors so we used to have to follow Clause 4.13.3,

Clause 4.13.3 - An appliance with an input up to and including 400 000 Btuh (120 kW) and certified for installation on noncombustible flooring may be installed on a floor constructed of combustible material, provided that
(a) the floor is protected with at least two continuous courses of 4 in (100 mm) thick hollow masonry units covered with sheet metal at least 0.0195 in (0.56 mm) thick;
(b) the masonry units are arranged so that the hollow cores will permit air circulation through them; and
(c) the base as specified in Items (a) and (b) extends not less than 6 in (150 mm) beyond the sides of the appliance.

[tenletters]

Has anyone tried the nut and bolt approach to leveling in the Carrier manual? https://www.manualslib.com/manual/734125/Carrier-58mvb.html?page=19#manual

I'm sure it's in others, but I've only noticed it in theirs.

[Admin]

Interesting, I've never noticed that before.