Boiler Install Critique - Undersized Piping and Bad Planning

VeritechVF1S

First, let me say that having read through countless posts on these forums, that this resource, including all of you who take the time to troubleshoot issues, are phenomenal. Alrighty, on to my problems:

I recently moved into a 1903 home in Western New York that had an incredibly old Pennco boiler serving a one-pipe system. I shopped around and settled on one of the largest local companies to do the install. I will not mention the specific price, but it was also the lowest of the quotes I received.

The new boiler gets installed, a Dunkirk PSB-4D (I grew up in Utica where the parent company is, so I thought that was kinda cool). To my, at the time, untrained eye, the install looked great! That is until noisy radiators and pipes plagued my daily life. I went through all of the usual troubleshooting: proper radiator and pipe pitch, functioning valves, proper radiator venting (there are no vents on the mains). Nothing worked, so I ended up just studying the manual from Dunkirk and it appears just about every single aspect of the install was done incorrectly. Feast your eyes on the following pictures, of which I am happy to provide more of:

- Right off the bat, I am aware that copper is a no-no. They at least used pressure fittings that are rated for steam. That they used copper may be the least of my worries.

- Next, they used a reducer coming out of the boiler, so instead of the recommended 2.5" size pipe, they reduced it to 2". I can't imagine why else this would be done, other than to save cost. Effectively, this is just increasing the velocity of steam in the system as it leaves the boiler, correct?

- Moving on, the height from the two risers to the bottom of the header is only about 22.5", rather than 24". So not only is the steam coming out faster than it should, the steam is also likely to be wet.

- The 15" requirement from the header to the takeoffs may have been met, but I'm measuring around a 90 degree bend. The takeoff's themselves seem unusual, but I'm not sure if they are actually problematic or not.

- The returns seem very oddly connected, and I would expect them to be piped in a way as to drop straight down. I'm realizing now I didn't take too great of a picture to illustrate what's going on there. I'm writing this from memory at the moment, and I can't be sure if all of the return piping is 1.5" as it is supposed to be.

- The Hartford loop has no drain? Or is the drain nearby sufficient? I wouldn't think so. I have used that drain to empty the boiler a couple times as the water quality has become bad. I'm not sure whether or not it was skimmed after the installation.

Any other thoughts? While I get that if it is possible to use two steam risers then that is the better choice, I can't help but feel this would have been a much easier install if they just had one riser coming from the rear with the header coming towards the front of the boiler and then 90 degrees left to the mains. Really, I'm just doing some fact finding so that I can start the process of having the install completely redone. Thanks!

ethicalpaul

This actually isn't so bad. There is so much more wrong they could have done, but the layout itself is pretty good.

Probably they didn't skim the boiler and it has a bunch of oil in it which is causing it to carry over water into your mains. Do some searching for "skimming" in the forum and see if it seems like they did that. If not, it's rather straightforward. They did leave you a Tee at one of the steam outlets from the boiler, so it should be easy.

The Dunkirk design is my least favorite, but they did pipe both steam outlets and that's the most important thing that is specific to your boiler.

VeritechVF1S

Thanks for the comment! Am I overthinking the 2.5" versus 2" piping? Does having two outlets reduce the velocity of the steam overall? By that I mean, say they piped it with one 2" riser instead of two. Would the steam velocity be higher in the one riser system versus the two riser system?

ethicalpaul

What model boiler is this?

Yes if they piped it with only 1 riser, the velocity would be up to twice as high at that point...of course they have a 2" header so the velocity will increase there, but hopefully having a slow velocity at the outlets will keep water from flying up as much (or at all)

VeritechVF1S

This is a Dunkirk PSB-4D. 112.5K BTU four section boiler. The manual says it can be piped with one riser, but it seems like if it can be done with two then that is preferred?

mattmia2

In some instructions for side outlet boilers I think there is a footnote for some of the smaller sizes that says it may be piped in one larger riser or 2 smaller risers.

The lack of swing joints on the risers is an issue but not your immediate problem.

AdmiralYoda

@VeritechVF1S It looks like that is a PSB-4D. According to the install manual you need ONE riser, not two. So the fact that you have two is already a bonus. Two 2" pipes have a cross sectional area of 6.28" where a single 2.5" has an area of 4.91". So I think two 2" pipes are an upgrade from the design minimum.

Two 2.5" pipes aren't required until you go to the five section boiler.

And I now wonder about copper with pressed fittings. Would that be a viable option since the solder joint is normally what fails?

VeritechVF1S

Here are the two diagrams from the manual for the sizing:

Here are the pertinent instructions from the manual regarding the pipe size. These are universal instructions as the manual is for every model in this line:

VeritechVF1S

These are the copper press fittings if anyone is curious: https://www.viega.us/en/products/ProPress.html

They are rated for low pressure steam applications and it would seem like they do offer some room for expansion. Time will tell, I suppose.

mattmia2

Copper isn't recommended because its coefficient of expansion is significantly greater than steel and it is a much better thermal conductor than steel so it condenses more steam than steel. Steel tends to get heated by the steam and retain some of that heat.

The lack of swing joints means that the expansion and contraction of the copper is going to try to pull the sections of the boiler apart(swing joints are requires with steel for the same reason)

ethicalpaul

I had that size boiler with a single 2" riser and header and the header was horrifically incorrect and I got it running with completely dry steam with just a little attention (clean water, some treatment added to get the ph to 10-11, main venting).

I am confident that you will be fine with this boiler. If it is actually throwing water into the mains, I'm quite certain it is due to water quality, not the piping quality.

Like yoda said, that boiler requires a single riser at 2" so you are twice as good there. Yes your header is slightly undersized but it's fine. And they even piped the drips on what appears to be a counterflow design. There are people in this forum WAY worse off.

VeritechVF1S

@ethicalpaul I'm glad to hear that it isn't as bad as I first thought! I did just speak with the rep in charge of my install and they told me they'd come back in and do a drop header to increase that height I mentioned from roughly 22.5" to probably something closer to 26" if I had to guess. I'm just glad to know that the 2" piping is good in this case. Sadly, I wasn't there when it was first installed, but judging by the amount of time it seems that skimming would take, I can't imagine it was skimmed. I'll address that with them as there's no use guessing.

I'm still a bit unsure of exactly what a swing joint is and how it would be added to a system like this if anyone could help out with that! I understand it allows for expansion and contraction, but I'm unsure exactly where they should be.

jhewings

Since they are going to do a drop header you get swing joints so you are good. Swing joints are an extra elbow so the pipes can move a little.

EBEBRATT-Ed

I agree the layout is ok but the header is supposed to be the size of the boiler tapping which is 2 1/2 and they only use 2" so the fact that they used 2 risers doesn't help much

pedmec

Sorry, I have a different opinion of the copper. You need to ditch the copper. It's working against the steam. you have a counterflow system, as evident by the drip tee's at the beginning of your main. Those are there to allow the condensate to drain back into the return of the boiler so it doesn't drain into the header and kill the steam. You need dry steam leaving the boiler but the copper is increasing the condensating rate, causing wet steam to leave the boiler. this is causing the water hammer in the mains as the there is too much condensate forming in the main and in the trying to flow back against the incoming steam creating the water hammer.
:

VeritechVF1S

@pedmec thanks for your assessment! One of the issues I have with how the takeoffs are laid out, is that one is so close to the flue, I can't properly insulate it. I might be able to wrap some loose fiberglass wrap in that tight spot, but it may not help much. I do have 1" fiberglass on most of the mains and have been waiting to insulate the near boiler piping. I wonder if with a drop header and insulation if I will still see problems. Though, as @EBEBRATT-Ed mentioned, the header being undersized probably isn't helping.

pecmsg

When was Pro Press approved for Steam?

Long Beach Ed

Assuming those are Viega fittings and not some Chinese garbage knock-off, that installer spent some real money on them. While they are approved by Viega for steam up to five pounds pressure, your boiler is rated to operate to fifteen pounds and I don't believe many boiler manufacturers want them on a header. I certainly would never specify them or approve them for this service.

If the couplings to the steel are copper instead of brass there will be electrolysis problems.

VeritechVF1S

@pecmsg This is taken from the Viega website regarding approved applications:

pecmsg

@VeritechVF1S
Hot and Cold potable water not steam!

Pro press does make fittings rated for steam, those are not the ones!

PC7060

@pecmsg - the last line in the chart lists as approved for low pressure steam. 

pecmsg

Copper is bad enough. How are the pro press fitting going to hold up to the expansion and contraction?

dabrakeman

Seems insulating all the copper near boiler piping could help mitigate the increased condensation rate a bit. Do the steel mains as well.

VeritechVF1S

Thanks again for the comments everyone. The original installer is coming out tomorrow to tell me their plan for fixing the issues I have.