Exhausted...

[mgbinspect]

Here' one for the brain trust:

A 44,000 btu furnace with a draft inducing blower (right flue)

A 88,000 btu furnace with a draft inducing blower (center flue)

And a 75,000 btu gas water heater - gravity (left flue)

ALL share this flue. It seems to me that it should have stepped up another size after the third flue joined in. Undersized? Any thought?

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And, all three units are crammed into a 6 x 9 unvented room in the finished basement ... hmm....

[hausdok]

OK,

You know that with my second grade math skills I can't do the math for you but the flue must equal the largest connector plus 50% of all others. Get out a pencil.

ONE TEAM - ONE FIGHT!!!

Mike

[mgbinspect]

OK,

You know that with my second grade math skills I can't do the math for you but the flue must equal the largest connector plus 50% of all others. Get out a pencil.

ONE TEAM - ONE FIGHT!!!

Mike

That'll work.

Thanks.

[Marc]

OK,

You know that with my second grade math skills I can't do the math for you but the flue must equal the largest connector plus 50% of all others. Get out a pencil.

ONE TEAM - ONE FIGHT!!!

Mike

Do you mean that the cross sectional area of the main flue must equal the area of the largest flue plus 50% of the combined areas of the remaining flues? Where does this rule come from?

Marc

[mgbinspect]

I believe we're talking volume - a little geometry ala pi. Richtig?

If memory serves, it's V = 2 pi R

Nah. That can't be right. That's got to be circumfrence.

V = piR squared. I think that's it, but I'll look it up.

Yes pi R squared is correct.

[Marc]

Area of a circle = (Pi) times (Radius squared).

Pi = approximately 3.14

Sorry Mike O. I couldn't help it. []

Marc

[mgbinspect]

No prob. I haven't used any of those formulas since I left the drawing board. Many moons ago. I was reaching.

[David Meiland]

It would be worth finding out if there's spillage at the water heater draft diverter when the furnaces fire up.