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Exhaust Flue Piping

north star

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Joined
Oct 19, 2009
Messages
4,596
$ = $ = $ = $

I have some existing, natural gas, Forced Air [ Heating ] Units
that are being replaced with Infrared heaters........The FAU's

have exhaust flues that penetrate the roofing assembly.

A Contractor is proposing to remove the FAU's & install rain caps
on the exhaust pipes, and leave it like that.

QUESTION: Is there a Code section that "requires" the exhaust

piping to be removed when the appliances themselves are
removed ?..........We are using the `15 IFGC & the other `15
I-Codes.

Thanks ya`ll ! :cool:


$ = $ = $ = $
 
Energy code for building envelope would be where I would look...

C402.5 Air leakage—thermal envelope (Mandatory). The
thermal envelope of buildings shall comply with Sections
C402.5.1 through C402.5.8, or the building thermal envelope
shall be tested in accordance with ASTM E 779 at a pressure
differential of 0.3 inch water gauge (75 Pa) or an equivalent
method approved by the code official and deemed to comply
with the provisions of this section when the tested air leakage
rate of the building thermal envelope is not greater than 0.40
cfm/ft2 (0.2 L/s · m2). Where compliance is based on such
testing, the building shall also comply with Sections
C402.5.5, C402.5.6 and C402.5.7.
C402.5.1 Air barriers. A continuous air barrier shall be
provided throughout the building thermal envelope. The
air barriers shall be permitted to be located on the inside or
outside of the building envelope, located within the assemblies
composing the envelope, or any combination thereof.
The air barrier shall comply with Sections C402.5.1.1 and
C402.5.1.2.
 
If they "sealed it and stuffed it with insul, I would not be concerned....Maybe put a note on it on the roof side that says remove when reroofing?
 
I would take issue with the exhaust flue piping remaining in place, cite IFGC 305.1. “equipment and appliances shall be installed as required by the terms of their approval, in accordance with the conditions of listing....”

The flue is no longer serving an appliance as approved & intended, placing a cap or any other material not approved by the listing authority is a violation.
 
They should be removed so somebody in the future can't hook up an appliance without noticing that the vent is capped and suffocating everybody in the building.
 
This reminds me of an incident I had about 20 years ago. I reroofed a home and with the owners consent, removed the protruding portion of a dilapidated, unlined brick chimney that was a vestige from when kitchens had wood fired cookstoves. Later the owner informed me that the gas company would not turn the gas on due to the water heater being vented into the now roofed over chimney.
 
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