Drilling a hole in a furnace vent for energy audit

[RobertSmith]

I'm attending a energy audit class.

The instructor stated to drill a hole in the furnace flue to take measuremetns of the flue exhaust, then repair the hole.

This seems absurb to me; however, what are your thoughts on drilling a hole into flue. Void warranties? How would you repair

Robert

[Ron Bibler]

Some remove a screw and probe in from the side. then just put the screw back after testing:D

Best

Ron

[Scott Patterson]

I'm attending a energy audit class.

The instructor stated to drill a hole in the furnace flue to take measuremetns of the flue exhaust, then repair the hole.

This seems absurb to me; however, what are your thoughts on drilling a hole into flue. Void warranties? How would you repair

brett

Well, I would like to know how you properly repair a "B" vent pipe! I don't think it can be done....

Then I would also wonder why an energy audit would involve taking flue gas measurements? As a former energy rater I have never heard of this being done on a normal energy audit.

Sounds like the class/instructor might be a little on the questionable side as far as the information it/he is trying to teach.

[Raymond Wand]

An energy audit was done on my home last fall. At the time I had an oil fired furnace and the energy auditor never tested the stack temp and gasses. Why would there be a need to particularly given that the audit is also non invasive and is essentially visual in nature?

[RobertSmith]

The instructor was citing all the associations, organizations, stds, etc that BPI had listed in the back of the book. I then noticed one that was missing. So I HAD to asked.... "How come the IRC isn't listed?"

Instructors response: "What is the IRC?"

Take a gun and shoot me now...

Rob

[Bob Harper]

Bacharach has contacted a number of vent mfrs. and asked them for a ruling, which is available on their website. For oil, you usually have single walled chimney connector to drill through but can be type L vent, which is constructed just like Bvent except ss inner liner. Gas can be either single walled or B-vent. CatIII is AL29-4C ss single walled under pos. pressure as is Cat IV PVC. The generally accepted method of doing this is to use red RTV silicone (650 intermittent/ 600F cont.) to plug a test hole. Most AHJs will allow this on Cat I and oil but the pos. pressure is a little more tricky. Yes, technically you void the warranty and listing of th eB or L vent if you drill a hole in it. That's all the more reason to use a draft hood connector to properly transition to single walled pipe, which can be drilled. To plug single walled pipe, there are snap in chrome buttons that work well. Don't have to be air tight on CatI and oil and are easily removed.

As for PVC, I know some guys will drill a hole, test, then cut out that section and glue in another without the hole.

On a draft hood equipped WH, you drill down through the draft hood so your probe projects down the flue for combustion sampling---draft readings are taken downstream of draft hoods and baro. dampers.

Overall, the BPI is a pretty good program but they do need to update some information. For instance, they still reference ASHRAE 62.2-1989 rev. instead of the 2007 (q 3 yrs).

HTH,
Bob

[DavidR]

Drilling is the only way you are going to be able to test a combustion appliance properly.

If anybody wants copies of the letters on how to seal B-vent let me know.
That small hole drilled in the B-vent is straining a gnat, ot's of other issues that will cause more problems than that.

[Scott Patterson]

The instructor was citing all the associations, organizations, stds, etc that BPI had listed in the back of the book. I then noticed one that was missing. So I HAD to asked.... "How come the IRC isn't listed?"

Instructors response: "What is the IRC?"

Take a gun and shoot me now...

Rob

That should give you and everyone else a clue as to the quality of this type of energy audit program.

I must admit I have never heard of BPI, so I had to Google them. I have heard of a couple of their BOD members, but that it about it.

[Ted Menelly]

I just inspected home that had an audit.

I bet you can guess most of the concerns I found at this new home...... Yep....Almost all energy concern items. for gosh sakes, missing insulation everywhere. Air blowing from every part of the units in the attic. Leaking duct connections and plenum connections. Attic stairs not insulated in the slightest. caulking needed everywhere. etc etc etc etc

The bbuilder sent the auditer, HVAC and insulation guys back and I bet you know what they said about my inspection...Yep...you got it...I did not know what I was talking about.

I sent the pictures and thermometer readings about everything I wrote up . Yes, they wound up fixing it all.

The rest was grading and drainage which of course the grounds folks said I did not know what I was talking about. The builder did not need me there. He just looked at what was on my report and had alal the inground drains reworked and sprinklers blowing know where repositioned.

I do believe I just made an inspection deal with the buider. Yes, plumbing, electric and all the rest as well as granite counter and cabinet installation concerns etc.