Megapress in steam near boiler piping

Paul_87

I am starting to see some steam boilers piped with black pipe and stainless megapress fittings with the green dot on them which I’m told are for steam. Just wondering what people’s opinions are on this. We thread all steam piping but if it’s ok to megapress maybe I need to think about using it.

Danny Scully

3 words @Paul, BE A MAN. Just kidding, but in all honestly I’ll never do it. I slap the dead men in the face too much with pvc, pex and press. I have to keep them smiling down upon me when I’m working on steam

nicholas bonham-carter

I’m sure it saves time, but at what cost?
What would the maximum diameter of piping be, when used with those fittings? Some jobs will need 3 inch pipe.
A drop header can be built with stock sized nipples, with only a few custom lengths needed for the connection to the existing piping. Those lengths could be cut and threaded back at the shop, if you want to avoid lugging a large threader down to the job.—NBC

Snowmelt

I only done smaller boiler with 2 inch nothing 3 inch as of yet I am able to do the near boiler piping with all nipples and not one cut. I am going to say for me its kinda easy to pipe with black pipe. if I had a 3 inch where I couldn't thread it together I would use 1 maybe 2 coupling or elbows or combination but it has to be 3 inch 2 I would thread. ( the viega guy became my friend and I have him over to me home a few times to chat)

Paul_87

I don’t plan to do it. I’m just more curious if it is acceptable or not. I guess according to Viega it is.

EBEBRATT-Ed

Time will tell how it holds up. I won't use it on steam yet. Have used it on condensate.

Mega Press 2 1/2"--4" is supposed to be on the way... don't know if it's out yet

GroundUp

I saw a Victaulic Roust-A-Bout (for hot water) on a 3" LP steam line yesterday holding 12 PSI, so there's that.... My bid was "too high" to make the necessary weld, so they called in a local pro with a Channel Lock (judging by the scarred up nuts) to fix it. MegaPress has got to be better than that, not?

RayWohlfarth

Hate to be the guy who brings this up. I was doing research for an article and found that the Copper Development Association says that copper can be used for steam heat. See the link:
https://www.copper.org/applications/plumbing/techcorner/cu_tube_steam_systems.html
Propress also states this fittings are approved for low pressure steam. See below
https://www.viega.us/content/dam/viega/aem_online_assets/download_assets/us/service_chart_english_wpex_0418.pdf

EBEBRATT-Ed

Propress & megapress are both approved for low pressure steam so obviously copper is as propress is.

Victaulic also has grooved steam fittings now but the ROUST a Bout that @groundup saw will probably not make a year.

And so CSST, Gastite etc is approved for gas and it's made out of tinfoil.

You get what you pay for

The Steam Whisperer

Soldered copper has been used for steam at least since WW II on the Mini tube systems ( Turbonics), However, the branches were all soft copper which allows for a lot of movement without damage to the piping or stress on the fittings. However, IMO, using any gasketed fitting on pressurized plumbing or heating lines, especially high temperature ones, is going to be bad in the long term. We see gaskets fail at hot water pump flanges due to age. The plastic gaskets in Weil steam boilers only last about 25 years before failing. What to you think the life will be when the gasket is not only subject to heat but also twisting from pipe expansion? Yes faster to put together, but I bet ,also faster to come apart. I suspect these fittings will ultimately will be another Kitec or Heatway/ Goodyear catastrophe.

ChrisJ

Well, I'll add this.

Every steam valve has a packing which is essentially a gasket. Yeah, they often need adjustment after a long time, but they are also set up to allow movement. For some reason everyone accepts them because "they've always been there". Apparently if "the deadmen" did it, it's always ok. The deadmen would've used press fittings if it existed, I promise.

The rubber O rings should allow for some movement, which could be a good thing.

I don't know what press fittings use, but I've seen some types of rubber turn to crap in a few years while other types seem to last virtually forever. Silicone for example seems to be pretty durable.


Honestly, if the boiler is piped properly and a guy wants to use steam rated megapress, I say by all means go for it. The important part is that it's piped properly. I'd take that over an improper headerless mess even if it's done in all threaded black iron.

Tinman

The future is now. I think MegaPress would be ok if the installer followed the same detail that Weil requires on their 88s using welded piped, the use of threaded joints at specific spots on the near boiler piping that allows movement.

ChrisJ

Stephen Minnich said:

The future is now. I think MegaPress would be ok if the installer followed the same detail that Weil requires on their 88s using welded piped, the use of threaded joints at specific spots on the near boiler piping that allows movement.

I still want to see actual proof that 20+ year old threaded joints allow any movement at all after being steam cleaned for all of those years. I certainly couldn't get them to move.

I would also expect an NPT joint to slowly loosen up and start leaking.

Tinman

I think the proof is already there. Ever see one crack or a pipe crack early because it didn’t have threaded joints?

Tinman

And steam is much stronger than you or I.

ChrisJ

Stephen Minnich said:

I think the proof is already there. Ever see one crack or a pipe crack early because it didn’t have threaded joints?

I haven't, no.

Paul_87

How would you know the reason it cracked was because it has or does not have threaded pipe?

EBEBRATT-Ed

I generally see propress, megapress and vic. as a way to get from point A to point B with hot or chilled water. For steam it's too early to tell how these systems hold up but a boiler header with propress, copper is subjected to a lot of stress because the copper expands a lot more than steel weather it's soldered or pressed. Victaulic new steam fittings ..time will tell.

Plus the cost of some of these systems is outrageous. I know you have to look at the installed cost (labor and material).

Vctaulic is a good system for water. The only failures I have seen are on systems allowed to run at 200 deg or higher. Not cheap but has many benefits, easy to take apart, make changes or additions.

Tinman

@Paul -There is a reason why manufacturer’s require and/or suggest specific piping methods; and they always do on steam and mod cons. If someone decides to pipe a steam boiler with all welded pipe or copper, that’s on them.

I don’t use the tools anymore but when I did, my M.O. was to follow best practices and manufacturer’s installation manuals.

GroundUp

@EBEBRATT-Ed I agree with the Vic. While some may disprove, I really like the stuff. Miles and miles of pipe and tens of thousands of fittings and couplings later, I have yet to see a failure unrelated to high temps or improper installation. On the other hand, I have personally replaced thousands of failed Gruvlok couplings. Just finished up a hospital a few weeks ago where we replaced every single coupling in the entire building following a boiler room remodel where we swapped to mod/cons and lowered operating temp from 170 to 135. It was done in steps so as to not kill the whole system and once the operating temp got down to about 150 some fittings started dripping. At 140 a lot were dripping. At 135 many were pouring. I just did the final tally for billing yesterday actually- 4,263 Gruvlok couplings were replaced with Victaulic, and this hospital was built in 2006. That 8 days with no heating system was a real kick in the nuts for someone above my pay grade. But they're fixed up now!

Dave0176

I’ll stick with my Ridgid 141 and 300 and keep making pipe threads. With me it’s not about production it’s about pride and the actual enjoyment of doing this job. To me there is something beautiful about threaded fittings and pipe.

Propress, megapress, and vic, to me are just speedy, generic looking jobs. Just shows the plumber couldn’t wait to get out of there. That’s my opinion anyway.

GroundUp

Dave0176 said:

I’ll stick with my Ridgid 141 and 300 and keep making pipe threads. With me it’s not about production it’s about pride and the actual enjoyment of doing this job. To me there is something beautiful about threaded fittings and pipe.

Propress, megapress, and vic, to me are just speedy, generic looking jobs. Just shows the plumber couldn’t wait to get out of there. That’s my opinion anyway.

Will you be threading those mile long 6" hot water mains too?

I'm with ya, I'll thread and sweat anything I can before I'll touch press stuff but there is no substitute for grooved anymore. Threading or welding 6" low pressure hot or chilled water isn't even an option anymore if you want to get the job.

Gordy

All I have to say about press fittings in general is this.

There is a lot of liability out there for what the manufacturers say they can be used for. With testing methods today I would think all the cycling of expansion, contraction, torque, fluid makeup etc. has been covered. You would hope.

If not someone is going to be in huge financial trouble in the upcoming years. who will the owners of the final product drag into law suits if frequent failures rear their ugly head?

EBEBRATT-Ed

@dave0176, agree with the threading. Threaded, sweat and welded are time proven. Welding gets knocked for the labor involved but in most cases it's will last a lifetime.

@GroundUp

Never used groovelock. The only time I have had vic problems was on overheated systems. Had a couple of jobs that heated with steam to water heat exchangers. When the Spence valves crapped out they overheated the water side up over 200deg.

The older Vic 107 couplings were rated 235 deg . The newer 107s are rated 250 deg. I do not believe their ratings I tthink anything over 200 is ng with them. We had the same issue with vic on overheated systems. The building became a shower stall when the water cooled down. Heat it back up the dripping stopped. I have also had vic job with the wrong gaskets (nitrile used on compressed air systems) was installed on the water system.

When the gaskets get overheated they loose their stretch. Had the Vic rep in on this. Other than that they are a great system but fittings are not cheap$$$$$ and it take a lot of couplings.

JohnNY

RayWohlfarth said:

Hate to be the guy who brings this up. I was doing research for an article and found that the Copper Development Association says that copper can be used for steam heat.

I'll bet the Copper Development Association says copper can be eaten for breakfast.

The Steam Whisperer

Interesting discussion. Most of what you guys have said seems to support my initial concerns. HIgher temps mean decreased life of the plastic or rubber o rings. Some materials hold up much better over time, I agree, however, I would suspect Weil is using the best material they can and I still see a max life of about 25 years for the gaskets. The failures related to welded headers on CI boiler are not in the piping, but in the boiler. The expansion and contraction leverages the sections and opens and closes the tolerances of the seals between the sections repeatedly with ever heat up and cool down cycle of the header. I understand the leaks can't be noticed initially, but overtime they get worse and worse. The pattern we see is on welded headers with boilers have 2 or more risers is where the problems develop. The typical life we see on the Weil LGB steamers is 14 years when set up this way. In fact we have been told by clients of one of the biggest LGB installers here in Chicago that the installer tells them that 14 years is the normal life for a steam boiler. On LGB's with only a single riser, we see about 25 year life. It's interesting how the single riser LGB's fail, one year no detectible leaks and the next every gasket is leaking.

IMO, if you are installing a 25 year plastic gasketed steam boiler use the press fittings for the near boiler piping.. They will probably all fail about the same time. If you are installing a 40 to 50 year heavy duty cast iron boiler and especially a steel boiler ( 100 years life?), don't use the press fittings. As for our installs, we have the piping all laid out before hand and precut so it just needs to be spun together and some adjustments made in nipple length to make up any differences. On a big job the final connections are welded.

PMJ

The thing is that there just is no substitute for actual field testing over actually all the years. Until those years actually go by how long new methods will last in any application is just speculation. That there never will be a better way is obviously not a reasonable position to take...of course there will. But it won't/can't actually replace the already proven methods and satisfy everyone until it is actually tested over enough years. In the mean time the speculation and the testing continues! That is a good thing.

I must admit I agree with those who find beauty in the clearly proven method of threaded pipe with steam. To me it is quite possible that the beauty I see is an image very much enhanced by the fact that I am looking at something I know for absolute certain will last a very long time. Old fashioned I suppose, but I still find such things immensely satisfying.

ChrisJ

PMJ said:

The thing is that there just is no substitute for actual field testing over actually all the years. Until those years actually go by how long new methods will last in any application is just speculation. That there never will be a better way is obviously not a reasonable position to take...of course there will. But it won't/can't actually replace the already proven methods and satisfy everyone until it is actually tested over enough years. In the mean time the speculation and the testing continues! That is a good thing.

I must admit I agree with those who find beauty in the clearly proven method of threaded pipe with steam. To me it is quite possible that the beauty I see is an image very much enhanced by the fact that I am looking at something I know for absolute certain will last a very long time. Old fashioned I suppose, but I still find such things immensely satisfying.

I can understand this, however I don't see anyone doing threaded galvanized in plumbing systems. Conduit looks far nicer for electrical work yet we rarely see it in residential.

I did threaded for my own installation, and probably would again.

I guess my point is, we don't know the new methods are bad yet. They very well might not be.

PMJ

I guess my point is, we don't know the new methods are bad yet. They very well might not be.

Right. We just don't know and have no way to know now. Only time will tell.

PMJ

@The Steam Whisperer , what would have been the materials in the assembly of my 1956 Bryant boiler that have lasted so well?

R Mannino

Anybody here driving a car with a carburetor on it?

The Steam Whisperer

I believe all the old cast iron boiler were assembled with steel or cast iron machined push nipples, just like the old radiators. They were a metal to metal seal. That's one of the reasons I like the Peerless 63/64 series plus they are really heavy.

Gordy

The carburetor wasn’t exactly the best means of combining fuel, and air for combustion. Diesel engines on the he other hand always had a form of fuel injection. It took a while for gas engines to catch up.

R Mannino

A lot of people didn't embrace fuel injected gasoline engines at first.

ericm1966

Had to do it- i have piped in 150,000 btu steam boiler in all megapress fittings 2 inch on the header and 1 1/4 on the return and hartford loop. Skimmed the boiler well. Note i do have all black iron back up fittings as should any of it fail. Iam running about 1psi maybe a little less which is heating the house up just fine - very curious to see how long the o rings last and its one of my owm properties. Time will tell. will post pictures at a later date.

Dave0176

It’ll probably be fine. However a 2” header on a 150,000 BTU input is small.

Tinman

If it were me, I'd be more than willing to try it but I would have checked with the boiler manufacturer first. I would think most would require a few critical swing joints to protect the sections from cracking if something wants to move. CYA.

coelcanth

Dave0176 said:

It’ll probably be fine. However a 2” header on a 150,000 BTU input is small.

i have a 175,000 BTU boiler and the manual specifies two 2" risers into a minimum 2" header... the takeoffs for mains are 2" as well..

would there be any advantage to going with a 3" header using 3x3x2" tees instead ??

Gsmith

Absolutely, anytime you can slow the steam velocity down, which will happen in the larger header, more water can drop out, hence drier steam goes to the risers to the mains. All good.

EBEBRATT-Ed

As long as it's piped to the boiler mfg minimum requirements you should be ok.

some prefer to over size headers and risers it cost more $$. but can give you drier steam.

Problem is I don't think megapress larger that 2" is available yet.............supposed to be on it's way.


Since megapress is approved for steam you would think?? (hope) the manufacturer has checked expansion and contraction issues....not holding my breath

Ironman

Mega Press XL is now available in 2 1/2" - 4".