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Chuck Kaatz
11-25-2011, 09:45 AM
What is the need for a conduit or pipe entering a masonry chimney.
I have seen this before with a ridged pipe.

Raymond Wand
11-25-2011, 11:59 AM
There should be no conduit. However three things come to mind.

1. A drainage tube for condensate or rain that may get into the chimney via the top. But having said that I have never seen a conduit for drainage?

2. Past electrical installation going to outside?

3. Conduit for protection for former copper gas line to bar-b-que?

Bob Harper
11-25-2011, 04:15 PM
Is that a combustible board mortared into the breaching just above the connector? If so, its gotta go.

John Kogel
11-26-2011, 05:13 PM
It could be worse. You could have a flower pot hanging out of your chimney. :D

Rich Goeken
11-28-2011, 06:06 AM
It could be worse. You could have a flower pot hanging out of your chimney. :D

Future Hothouse? :D

Tom Kio
11-30-2011, 12:18 PM
May be it is a combustible board mortared into the breaching just above the connector.

Raymond Wand
11-30-2011, 12:30 PM
It doesn't appear to be wood it looks like a beige brick.

Bart Ogden
12-05-2011, 08:30 AM
Chuck,

We've seen those installed many times as condensation drain tubes.

Our recommendation is to do a Level 2 Inspection, which "usually" leads to a finding that the existing flue is over sized for the appliance venting load - the cause of the condensation.

Bart Ogden
Wichita, KS
NCSGTAC



What is the need for a conduit or pipe entering a masonry chimney.
I have seen this before with a ridged pipe.

Chuck Kaatz
01-24-2013, 09:28 AM
Chuck,

We've seen those installed many times as condensation drain tubes.

Our recommendation is to do a Level 2 Inspection, which "usually" leads to a finding that the existing flue is over sized for the appliance venting load - the cause of the condensation.

Bart Ogden
Wichita, KS
NCSGTAC

How is the condensation collected

Lou Curley
01-24-2013, 06:27 PM
How is the condensation collected

Call for the level 2 inspection. There shouldn't be a conduit into the chimney to begin with. If there's so much condensation in the flue that somebody had to install a drain, there's something seriously wrong with the system. Where they would collect the condensation is irrelevant.

Markus Keller
01-24-2013, 07:50 PM
The overall opening looks like it was much larger. My guess is the opening may have had one of those old metal cleanouts with the drain port. Can't remember what they were called. Bob? Seen so many of them over the years. Looks like they may have removed it, closed up the larger hole and installed the emt as a drain.
Regardless it should go; especially since there is a lower clean out opening. You wouldn't want to leave it and have someone later on think its a good way to get electric upstairs.

Bob Harper
01-25-2013, 09:20 AM
If this conduit is not directly attached to the base of a listed chimney liner and does not have a trap then it must go. Cannot go putting holes in chimneys willy nilly.

If that connector is galvanized steel mortared into the wall, it must be changed to stainless steel or encased in a clay thimble. Regardless, the discharge end of the connector must be flush with the face of the flue wall and sealed with furnace cement.

The cleanout is too low--should be 12" below the breaching.

If you are getting condensation of flue gases, you must look at the root causes:
-cold flue
-low stack temps
-high RH in the CAZ
-lack of post purge

A cold exterior chimney should be relined-period
A heater should get combustion analysis by a certified pro and tweaked as needed-period
The Rh% in the CAZ should be kept reasonably low because that humidity adds to the flue gas moisture from the oxidation of the fuel-period
Post purge clears any unburned gases but it also tends to dry the last moisture off the flue walls as they cool down. As the stack temps drop below dewpoint, it doesn't matter if there is no humidity in the stack air to cool and condense. This can easily be added to most appliances by a pro trained and certified in combustion analysis.

I've been getting calls from all over the country this week about condensation issues.

HTH