Stainless steel 316L

S Ebels

Never had the occasion or need to use anything other than Viessmann's concentric venting. Using stainless is generally done if vent lengths exceed what the concentric can handle. You lose the balanced flue feature if you go with a single pipe vent.

Couderay

316L/pvc

Can 316L stainless pipe be used in place of pvc for venting on a condensing boiler.

Ted_5

Better choice

> Can 316L stainless pipe be used in place of pvc

> for venting on a condensing boiler.



Yes, it can. It is an approved boiler venting material.

Ted

Brad White_167

Yes, but

why would you want to? You must have some stock you need to use up! Stuff is not cheap but if you have it or can afford it, heck, why not?

316L has lower carbon than normal 316 and is the choice for many condensing boiler heat exchangers so I cannot see why it would not work for venting.

Viessmann uses a 316T (titanium) alloy which only they have.

Personally I think AL29-4C looks nicer and you can shave looking at it.

EDIT: The other points below are very well taken- my assumption is that of a choice of materials it is sanctioned by the manufacturer and manufactured as a system for the purpose.

Guy_6

can or should

Be careful-even though a material may function well, it will not release you from liability should anything happen. The safe bet is to either use what is specified in the manual or get written consent from the manufacturer.

S Ebels

Back up a step

What prompts your question in the first place?

J.C.A._3

Other than Viessman,

All German manufacturers specify stainless flue piping for their units in Europe.(I believe it's the law)

Viessman uses a similar concentric vent like the ones we get here, but I'm not sure of the material.

Personally, I'd like to have the option of using something other than PVC for vents. I feel it "cheapens" the look of an otherwise fine and beautiful appliance. I'd use it if the customer wouldn't mind paying for it. Nuff said? Chris

JimH

> All German manufacturers specify stainless flue

> piping for their units in Europe.(I believe it's

> the law)

>

> Viessman uses a similar concentric

> vent like the ones we get here, but I'm not sure

> of the material.

>

> Personally, I'd like to have

> the option of using something other than PVC for

> vents. I feel it "cheapens" the look of an

> otherwise fine and beautiful appliance. I'd use

> it if the customer wouldn't mind paying for it.

> Nuff said? Chris



I'm considering a vito install right now, and I'll definitely be asking what
the cost delta is for stainless exhaust. PVC is extremely toxic to manufacture,
not recyclable, and ougasses hydrochloric acid when it burns. I found it note-
worthy that the plastic venting material Viessmann sells in the US is PP.

Has anybody seen a vito install in the US with SS flue?

JimH

JimH

I'm considering a vito install right now, and I'll definitely be asking what
the cost delta is for stainless exhaust. PVC is extremely toxic to manufacture,
not recyclable, and ougasses hydrochloric acid when it burns. I found it note-
worthy that the plastic venting material Viessmann sells in the US is PP.

Has anybody seen a vito install in the US with SS flue?

JimH

JimH

oh....

I thought the euro installs might have concentric stainlesss.

Perry_3

The ballanced flue feature of the concentric vent is..

really not that necessary from an engineering design standpoint.

However, for several reasons the Vitodens concentric vent is the way to go IF you are going to use outdoor air for boiler air supply in a "sealed" combustion unit.

If you are OK with using indoor air for the boiler air supply; Viessmann sells sevearal adapter kits to the common US suppliers of SS exhaust vents. The fact that the inlet air pressure drop and the exhaust vent pressure drops are not matched is not an issue.

Under no condition am I aware where Viessmann approves the use of PVC for exhaust venting for the Vitodens.

I do note that the Vitodens concentric venting is almost certainly cheaper than using a SS exhuast system.

It is also my understanding that we are using the same concentric venting system that is used in Europe. All the parts are in metric lengths (but ft conversions are supplied) - and I did not check the diameters; but I'll bet that they are really metric as well.

By the way, the Vitodens is a great boiler. Enjoy it.

An example of what the Vitodens Concentric venting system looks like is below (this only shows the start of the vent run; about 8 ft horizonatal, 2 ft up in a 1st floor closet, then 2 ft out the house wall well above the snow line).

Note the gallon jug under the sink does not fill up. It is a deflector for the laundry drains. When I insulated the wall and studed it I moved the laundry sink out about 8" from where it used to be and the sink drain no longer lines up with the floor basin. Something to fix in the future.

I also know that I am pumping "to" the LLH and not away from it. A lessor issue than others I had to get right with the installation (I was not going to win them all - so I picked the issues I fought for).


Perry

justme_2

Vitodens venting

Consult Viessmann, they have the Vitodens approved for many venting configurations.

Couderay

Why the question

Yes I do have 316L in 3" and 4" and after reading a thread on PVC from awhile ago, I thought that maybe I would convert my vent to stainless. The stainless I have is schedule 10. Boiler is a 140M munchkin

JimH

Thanks for the photo, Perry! I really enjoyed reading your installation story,
and I was wondering what it looked like! It shows what an involved HO, who's
willing to dig deep into the technical documents can accomplish...

Just curious, when the iron soil pipe is up for replacement, will you insist on
iron with caulked joints, or go with PVC?

;-)

-JIm H

Ted_5

Jim

If you are with in the vent length requirements of the Viessmann venting, then use the pipe in a pipe venting. We have used SS a few times on Vitodens, but that is only because we needed to go thru the roof and had the exceed the maximum length of the concentric pipe. If you use SS, then the boiler is no longer sealed combustion. At that point it is room air dependent. The only way Viessmann allows SS venting is going thru the roof, side wall is not an option.

Ted