Condensing furnace flue install

[Ponyboy]

Well I just shut down a furnace today when I found the flue disconnected from the furnace. A single mom and two kids live in the house. The rust around the flue connection indicates it has been disconnected for some time.

As I followed the plastic flue to the foundation it connects into a flex metal gas flue and disappears into the old oil furnace chimney liner. Note the connector is a plumbing drain connector between the plastic and metal. This is a remodeled house (2005 second story addition) where the brick chimney has been extended and enclosed in wood framing. No gas vents outside, just one for the fireplace.

Of course the home owner flipped out called the contractor who had some choice words for me!

Looking for some gas flue installation language so I can have a very accurate report.

I was just informed the seller will have a furnace contractor at the house 8:30 AM tomorrow and they want copy of my findings about the flue. What would you say?

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[StevenT]

Heating System;

Flu pipe is disconnected at the heating unit.

Questionable installation materials.

Have a qualified heating technician make necessary repairs.

Note: Since this is a serious health/safety issue, I notified the homeowner, and shut down the system.

[hausdok]

Okay,

It looks to me like they've fully-lined that masonry flue with that flex. Did they cap it as well and seal it so that it's essentially now a double-walled flue? If so, and the transition coupling isn't leaking, and the condensate line is clear and draining, and the condensate pump is functioning correctly, and the the flue gases are being conveyed all the way to the outside, what's the issue?

It looks like a BDP (Bryant, Daylight, Payne) Plus 90 non-direct vent application. Did you look at the install instructions. I seem to recall reading something in a BDP install manual once that said, "All models chimney-friendly when an accessory vent kit is used." The question is, is that the accessory vent kit they're talking about?

ONE TEAM - ONE FIGHT!!!

Mike

[Jim Katen]

Originally posted by Ponyboy

Well I just shut down a furnace today when I found the flue disconnected from the furnace. A single mom and two kids live in the house. The rust around the flue connection indicates it has been disconnected for some time.

I don't see the disconnection in your picture. If you're trying to build a case for dangerous condition, take a picture that show that condition clearly.

As I followed the plastic flue to the foundation it connects into a flex metal gas flue and disappears into the old oil furnace chimney liner. Note the connector is a plumbing drain connector between the plastic and metal. This is a remodeled house (2005 second story addition) where the brick chimney has been extended and enclosed in wood framing. No gas vents outside, just one for the fireplace.

Of course the home owner flipped out called the contractor who had some choice words for me!

Looking for some gas flue installation language so I can have a very accurate report.

I was just informed the seller will have a furnace contractor at the house 8:30 AM tomorrow and they want copy of my findings about the flue. What would you say?

This flue installation is dangerous. It can leak large amounts of carbon monoxide into the house and it might sicken or kill people.

- Jim Katen, Oregon

[Ponyboy]

Originally posted by hausdok

Okay,

It looks to me like they've fully-lined that masonry flue with that flex. Did they cap it as well and seal it so that it's essentially now a double-walled flue? If so, and the transition coupling isn't leaking, and the condensate line is clear and draining, and the condensate pump is functioning correctly, and the the flue gases are being conveyed all the way to the outside, what's the issue?

It looks like a BDP (Bryant, Daylight, Payne) Plus 90 non-direct vent application. Did you look at the install instructions. I seem to recall reading something in a BDP install manual once that said, "All models chimney-friendly when an accessory vent kit is used." The question is, is that the accessory vent kit they're talking about?

ONE TEAM - ONE FIGHT!!!

Mike

I have never seen a 90 plus venting up a chimney, ever. The vent would have to go up three stories. I have also been told you can not mix different exhaust systems together which is what has occured. Also I could not find an exterior vent location for the furnace.

[hausdok]

Hi,

Be that as it may, I 'm certain that I read something in a BDP install manual that said, "All models chimney-friendly when an accessory vent kit is used."

I don't make this stuff up. It was definitely in a BDP 90+ manual. If it were me (it's not), I'd get a look at the manual for that furnace and find out if that setup meets their definition of an "accessory vent kit." Personally, I don't think it does, but you won't know unless you check it out; will you?

OT - OF!!!

M.

[Jim Katen]

Originally posted by hausdok

Okay,

It looks to me like they've fully-lined that masonry flue with that flex. Did they cap it as well and seal it so that it's essentially now a double-walled flue? If so, and the transition coupling isn't leaking, and the condensate line is clear and draining, and the condensate pump is functioning correctly, and the the flue gases are being conveyed all the way to the outside, what's the issue?

The Cat IV exhaust gases are so cool and so moisture laden that they'll eat up that metal liner.

- Jim Katen, Oregon

[hausdok]

Hi Jim,

Isn't that stuff stainless steel? What effect will they have on SS?

OT - OF!!!

M.

[Jim Katen]

Originally posted by hausdok

Hi Jim,

Isn't that stuff stainless steel? What effect will they have on SS?

OT - OF!!!

M.

I don't know. I've never seen a cat IV furnace vent through anything other than plastic.

- Jim Katen, Oregon

[hausdok]

Hi All,

Well, I've got an answer from the horse's mouth, so to speak. I contacted Bryant and they referred me to their local distributor, Airefco (888-247-3326), who referred me to their on-call field representative out of Spokane.

He says there's no way that this installation would be factory approved. He says there's no problem venting it up through a chimney, but that the flue has to be an "approved material," that the approved materials are listed in the installation manual, and that there isn't any metal - aluminum or stainless steel - approved as a vent material for any of their 90+ units. He doesn't recall the 'chimney friendly' sentence, so he doesn't know what they were referring to. I suppose I could dig that back out again, but why bother? Brad has the answer he needs.

That should settle it for you, Brad.

I asked the gentleman to stop by TIJ once in a while and set us straight about anything in the HVAC forum that we're getting wrong. Hope to see him stop in sometime.

ONE TEAM - ONE FIGHT!!!

Mike

[sheetmetal80]

Find this guy and take the wheels off his truck. You can use chimmney just run pvc all the way up. should have ran comustion air or did he need beer money?

[hausdok]

Yes, PVC is an approved venting material. He didn't say they couldn't use PVC in a chimney; only metal flue materials.

OT - OF!!!

M.

[mthomas1]

Coming a bit late to this discussion, but it's the 80% AFUE furnaces that are "chimney friendly", not the Cat IV models.

[msteger]

I have also been told you can not mix different exhaust systems together which is what has occurred.

I also recall being told that you can't mix gas and oil appliances into the same flue (on the same level), but after calling it out many times in the past many years, I wanted to find out exactly where this 'rule' is documented and I could not find it anywhere. On page 138 of the Code Check Complete book it does say "OK to vent gas and oil to same chimney". So I stopped calling it out.

Any other opinions or documentation to prove otherwise?

[MechAcc]

Originally posted by hausdok

Hi,

Be that as it may, I 'm certain that I read something in a BDP install manual that said, "All models chimney-friendly when an accessory vent kit is used."

I don't make this stuff up. It was definitely in a BDP 90+ manual. If it were me (it's not), I'd get a look at the manual for that furnace and find out if that setup meets their definition of an "accessory vent kit." Personally, I don't think it does, but you won't know unless you check it out; will you?

OT - OF!!!

M.

90 percent efficiency furnaces are not accessory vent kit applicable.

Get a copy of the furnace installation manual.

They have increased from a 2 inch to a 3 inch on the horizontal. Nice water trap for a condensing furnace.

And I bet American Standard/ Trane wonders why this company has high warranty claims. Looks a silicone nitride igniter has already been replaced. Have only seen two of this style igniter bad, loads of the silicone carbide.

[MechAcc]

Originally posted by hausdok

Hi All,

Well, I've got an answer from the horse's mouth, so to speak. I contacted Bryant and they referred me to their local distributor, Airefco (888-247-3326), who referred me to their on-call field representative out of Spokane.

He says there's no way that this installation would be factory approved. He says there's no problem venting it up through a chimney, but that the flue has to be an "approved material," that the approved materials are listed in the installation manual, and that there isn't any metal - aluminum or stainless steel - approved as a vent material for any of their 90+ units. He doesn't recall the 'chimney friendly' sentence, so he doesn't know what they were referring to. I suppose I could dig that back out again, but why bother? Brad has the answer he needs.

That should settle it for you, Brad.

I asked the gentleman to stop by TIJ once in a while and set us straight about anything in the HVAC forum that we're getting wrong. Hope to see him stop in sometime.

ONE TEAM - ONE FIGHT!!!

Mike

That's good but that's not a Bryant 90 percenter. They all vent out the left or the right side of the cabinet. I stand with my observation that it's an American Standard/Trane furnace.