Plastic gas venting

EBEBRATT-Ed

MA will allow when replacing a gas fired appliance to reconnect the flue to existing PVC if:

the pipe is not compromised.

It is concealed and cannot be easily replaced without opening a wall.

It's the correct size.

The mfg. of the new appliance allows PVC.

New pipe must be installed where accessible.

There is an approved clamp that is rated 200 deg that made by Ideal. Ma. approval #G1-0122-000 that is approved to transition from PP pipe to PVC

EdTheHeaterMan

Good thing that I don't do work in Ma.

Come to think of it... I don't work anywhere anymore.

Retirement will do that to you.

realliveplumber

Can you please provide information on the approved transition clamp?

EBEBRATT-Ed

@realliveplumber All I know is the clamp is made by "Ideal" and has a yellow ban on it for gas and is rated 200 deg. I will try and look it up and post what I find.

#" is Ideal #6219Y8G Yellow band.

realliveplumber

@EBEBRATT-Ed . Thanks for the reply. Those yellow ideal bands are not listed to connect exhaust piping together. They are only listed for no hub soil pipe. I have a letter from Ideal Stating this.

Recently we installed a power vent water heater in a fairly new condo. The existing 3" exhaust piping in the condo was schedule 80 cpvc. Well one elbow was $100.00, and a 20' stick of pipe was over $300.00.

We piped to the existing pipe with sch 40 pvc, and connected the dissimilar materials together with a pvc male adaptor threaded into a cpvc female adaptor.

The local inspector said that I needed to use an "approved coupling", and that he had never seen it done like I did it before.

I told him baloney. Cite the section, or show me an approved coupling.

So we went round and round for a while, and he finally says i need to use a certain Rheem part number. I looked it up, and here it was the coupling that comes with a rheem power vent water heater, that is used to connect the exhaust pipe to the inducer motor. I laughed at that.

So anyway, I contact Rheem, they sent a letter stating that coupling is only listed for their water heater.

I contact Fernco, Mission Rubber Co., and Ideal, and have letters from all stating that none of their flexible elastomeric couplings are listed and approved to connect piping used for exhaust.

I contacted the State, and my installation was approved. I was told it is an approved way to connect dissimilar piping. The other would be flanges.

EBEBRATT-Ed

@real live plumber.

I can only tell you what I read in "New England Progress" and this is from Wayne Thomas PHCC president who used to be on the gas & plumbing board.

Question:I believe there is a yellow banded coupling made by Ideal accepted for gas venting to join accepted materials MA approval #G1-0122-000 I saw the clamp at a trade show and am looking for confirmation

Answer:In December 2021 the plumbing board approved the use of a clamp that could meet the 200 deg requirement As you can tell by the product acceptance # the coupling is approved for gas venting

Ideal should know this they had to go through the approval process with the board. The number above is the MA approval to use for venting. It's on the board website and you can look it up

Bob Harper

As stated above, this coupling is not tested nor listed for use with combustion venting. Just because someone tells you something is 'ok' to use don't make it right. Whomever approved this needs to be fired. This is designed for a low temperature, low pressure, liquid drain. If it leaks, it is a nuisance- not a life safety hazard.
However, when used for combustion venting, it will routinely see over its service life significantly higher temperatures than tested long term. The repeated heating and cooling cycles combined with the Hoop Stress may have unknown consequences to the fitting. These fittings are tested at 70C/ 158F max for 96 hrs. Not months. Not at repeated heating and cooling cycles. Not in a highly acidic bath. The bands must be torqued to 80 in lb. Who's going to re-torque those clamps over its service life? What is the test or inspection standard to determine if a pipe has been 'compromised'? None. Nobody can agree on one for UL 1738. The cement used on polymeric pipe usually carries a lower service rating than the pipe itself. Also, there was no mention of what types of pvc are allowed or if co-mingling is allowed. Is there any requirement or provision for pipe elongation and expansion? What is the requisite hanger spacing for horizontal and vertical applications? How do you make firestops for it?
So many problems with this venting yet we keep using it as if it has an unlimited service life. Most of the B-vent in the country has outlived its service life and should be replaced or revert to CAT IV appliances.

dko

The Ideal Tridon yellow was made to compete with the Husky White and Mission Blue 5/16 Hex couplings. They did not color the shield yellow for gas, only to differentiate from Husky orange/white/black, and Mission Blue.

Someone in MA just took advantage of the coincidence, read NH couplings use neoprene as the primary elastomer, and read neoprene can withstand high temperatures! That was probably the entire approval process.

realliveplumber

@EBEBRATT-Ed I am not arguing or trying to be disrespectful. I appreciate the discussion.

I had a NJ licensed plumbing inspector tell me I had to use this

https://www.supplyhouse.com/Rheem-SP20252-Rubber-Coupling-Power-Vent-Blower-Exhaust

One side of that Rheem part fit 3" plastic pipe, the other side did not, it was sized for Rheems exhaust blower.

He told me he was told it was approved by another inspector who is a very experienced inspector who "knows". My inspector was green. I told him flat out that he was absolutely wrong, and that he had better not tell anyone to use that coupling.

But, as expected, he wasn't man enough to admit he was wrong.

Anyway, unless something at Ideal changed in the last 6 weeks, they do not offer a listed, labeled flexible elastomeric coupling that has beed tested and approved to connect abs, pvc, or cpvc piping serving as an exhaust pipe for a fuel fired appliance. If the MA board approved it for use, so be it. But they are going down a slippery slope, because no manufacturer has.

I am only stating this so that whoever reads this thread in the future is aware that the safest way to connect dissimilar plastic pipe is with male and female adapters, or flanges.

realliveplumber

Oh and by the way, as of this moment I have a plain old 2" fernco connecting the pvc exhaust pipe for my power vent water heater in my basement. lol.

Been there for 6 years. Its exposed in the basement. No leaks or deterioration visible.

realliveplumber

@EBEBRATT-Ed @Bob Harper

Your statement that the MA board has listed an Ideal yellow no hub being listed on the MA board site for use with "Gas" is correct.

https://ma-dpl.my.salesforce-sites.com/MAPlumbingProducts/ppPlumbManFinal

realliveplumber

I wonder if Ideal is aware of this.

I really, really hope someone does not read that list someday and decide that the yellow no hub is approved to connect 2" gas pipe

EdTheHeaterMan

realliveplumber said:

I wonder if Ideal is aware of this.

I really, really hope someone does not read that list someday and decide that the yellow no hub is approved to connect 2" gas pipe

Maybe we just need to use a potato to cap off an old low pressure gas line.

Have you ever heard that story?

realliveplumber

@EdTheHeaterMan

We jammed a potato into a buddys parked car's exhaust pipe back in the day in Bridesburg.

Absolutely would not start.

Good times.

realliveplumber

Ideal calls them cast iron pipe couplings.

EdTheHeaterMan

realliveplumber said:

@EdTheHeaterMan

We jammed a potato into a buddys parked car's exhaust pipe back in the day in Bridesburg.

Absolutely would not start.

Good times.

That was YOU?

Do you remember Martin Fuel Oil Company, on the 2500 block of Orthodox Street?

EBEBRATT-Ed

@Bob Harper @realliveplumber

I am not here to argue this. I just stated what was in the magazine which is that Wayne Thomas former head of the Plumbing Board in Ma and Now executive of PHCC stated that the coupling is approved, and it is approved according to the MA website.


If anyone thinks that this has been approved without Ideals approval, I find that very difficult if not impossible to believe.

Those that do not work in MA may not know that all pipe, fittings, boilers furnaces etcetc etc MUST be approved by the state to be installed in Ma. This covers all plumbing and gas products.

I was involved (very little) in helping a gas burner MFG getting his equipment approved years ago.


This is not a simple process. You send in an application and fill out reems of paperwork to get product approval and then you go and sit before the Board. This not some white wash job where they just pass everything that comes across their desk.

@realliveplumber It's only approved for gas venting not gas piping


I regret even starting this post.

realliveplumber

EdTheHeaterMan said:

realliveplumber said:

@EdTheHeaterMan

We jammed a potato into a buddys parked car's exhaust pipe back in the day in Bridesburg.

Absolutely would not start.

Good times.

That was YOU?

Do you remember Martin Fuel Oil Company, on the 2500 block of Orthodox Street?

Yes, they serviced my Dads auto shop in Frankford for 20+ years.

realliveplumber

EBEBRATT-Ed said:

@Bob Harper @realliveplumber

I am not here to argue this. I just stated what was in the magazine which is that Wayne Thomas former head of the Plumbing Board in Ma and Now executive of PHCC stated that the coupling is approved, and it is approved according to the MA website.


If anyone thinks that this has been approved without Ideals approval, I find that very difficult if not impossible to believe.

Those that do not work in MA may not know that all pipe, fittings, boilers furnaces etcetc etc MUST be approved by the state to be installed in Ma. This covers all plumbing and gas products.

I was involved (very little) in helping a gas burner MFG getting his equipment approved years ago.


This is not a simple process. You send in an application and fill out reems of paperwork to get product approval and then you go and sit before the Board. This not some white wash job where they just pass everything that comes across their desk.

@realliveplumber It's only approved for gas venting not gas piping


I regret even starting this post.

@EBEBRATT-Ed Why would you regret it? No one is being disrespectful or argumentative.

I applaud you for starting this post. No one is being disrespectful or challenging. We are having an educated discussion and working through a very important topic.

You are absolutely correct in everything you have stated in this thread regarding the approval in MA.

This topic really need's attention, as it is life safety, and there is a lot of incorrect information out there on the interweb.

You should be proud to have brought attention to this. You very well may save a life or 2.

EdTheHeaterMan

realliveplumber said:

EdTheHeaterMan said:

realliveplumber said:

@EdTheHeaterMan

We jammed a potato into a buddys parked car's exhaust pipe back in the day in Bridesburg.

Absolutely would not start.

Good times.

That was YOU?

Do you remember Martin Fuel Oil Company, on the 2500 block of Orthodox Street?

Yes, they serviced my Dads auto shop in Frankford for 20+ years.

Frank Young and John Young were the owners of that fuel oil business. They sold it to Sunoco when they wanted to retire. "Small World this Oil industry"

Bob Harper

I was not busting balls here but on my soapbox about the continued confusion and disagreement in the industry about plastic combustion venting and the lack of viable standards.

ChrisJ

I find it interesting that the connector needs to be rated for 200f to connect to pvc which has a glass transition temperature of approximately 176F.

I'm curious why.

PeteA

since this topic is about the plastic vents, I was wondering if you can reduce the size of the PVC piping using standard PVC fittings, I don't mean just reduce it for no reason at all, I am talking about within the lengths allowed in the install manual because I see that many of the combi units have a range of PVC pipe sizes that they allow based on the length of the runs of pipe from the combi boiler itself and each of those reduced sizes has an adapter of some type at the exhaust or intake point of the boiler unit. but I was wondering since I already have 3" penetrations going out of my brick wall for the exhaust and intake but if I get a combi boiler that allows 2" venting can I use a PVC glued 3" to 2" reducer so I don't have to mess up the brick facade where the pipes come out of the house. I would only be looking to couple up to a short length that goes through the wall. The people that did the initial install did a neat job with the 2 3" pipes and I'm not sure my cement work around the pipes would be as neat if I reduce it to 2 2" PVC pipes. If there's no advantage, I could just rerun the 3" and pick up the pipes that way instead.

mattmia2

You would have to think about what happens to the condensate in the vent, make it so the transition doesn't trap condensate in the pipe.

tim smith

As far as I have been able to find over the years, there is no PP pipe mfrs who approve to go from their product to PVC. Or the other way. I could be wrong now but have gone down this road several times.
Tim

dko

PeteA

@tim smith I am not looking to mix and match different types of piping that itself is clearly spelled out that it should not B done that way I am simply asking if the schedule 40 PVC pipe can be reduced from 3 inch to 2 inch where it goes out the wall so I would have 2 inch going from the boiler to the 3 inch exit out the wall, all PVC and glued 

EBEBRATT-Ed

@PeteA

If the new boiler can use 2" based on the footage and fittings used why not just cut the 3" flush with the wall and slide the 2" through it. Seal it with HT silicone.

EBEBRATT-Ed

BF the high efficiency equipment came out you followed the code in your area and the mfg instructions for the older equipment which was a little more forgiving. That is still the case.

The code in a lot of areas have never caught up with the new equipment. So there is more reliance on the MFG instructions and less on the code where previously the opposite was true. When the first High efficiency boilers came out the inspectors were looking for low water cutoffs for example and Viessmann and Buderus were saying you don't need one we are sensing flow.......and that's just one example.

The Code panels don't seem to know how to handle the newer (now 25-30year) equipment and just rely on the MFG instructions.

Even now some MFGs still allow PVC (and there is at least 1 brand of PVC approved for venting) others want CPVC or PP

And it's an issue especially with the older high efficiency stuff at the end of it's life.

What do you tell a condo owner with a building full of boilers or furnaces where the flue goes up 3 floors and can't (or shouldn't be used) for the new appliances? Rip his walls apart I guess.

It's the MFGs fault for allowing PVC in the first place. Most all of it was never approved for venting and can't take the temp, the code allowed it by saying "follow the mfg instructions" now the owner pays the bill.


Since all this technology came from Europe what do they do?

I remember the first high efficiency equipment they said the condensate was harmless like you could drink it. How did that work out?

dko

Despite Navien's other issues, they are probably the only one who actually has a dip switch to limit exhaust temperature to 149F for when PVC is used. Will limit output though so not sure why you'd still run it PVC unless low temp design.
Burnham Alta has one that is 194F and still approves PVC.
Lochinvar Noble also approves PVC and is set at 215F.

Not allowing PVC will probably hurt sales, but no protection measures built in.

PeteA

@EBEBRATT-Ed Thats a great idea using the 3 inch as a sleeve through the brick wall to pass the 2 inch through, I will go that route when it comes time to run the pipe out.

PeteA

@EBEBRATT-Ed I see the concerns you listed for the sched 40 PVC. Do you personally prefer the PP for the venting? In my case I have a nice clear run for the new pipe since it's a sidewall vent and it passes parallel through the floor joists and only has one 90 in the run of about 15 feet of piping each (exhaust and intake)

dko

PP isn't that much more money than PVC. And you have a locking ring vs primer/cement. You waste any cut pipe as it has a hub. Comes in 1ft, 2ft, 3ft, 6ft, 10ft lengths so measure lengths needed instead of buying all 10ft lengths like you would with PVC.