Fixing a boiler Install...some questions

Knave72

For a residential installation of a PVSB-7D Dunkirk boiler which should have 2 risers but only has 1.

Here are the installation instructions...




Here is what my install looks like:




It would be great if the fix could simply be this:



But I'm guessing life can't be that easy...


Note the elbows shaded red in the installation instructions... how literal should this be followed - do I need to bend horizontal first before tee-ing the pipes together?

After the two risers are joined, is it okay to have that additional vertical riser before we tee off the mains or should the mains tee off at the same level as the risers come together?

Thanks for your thoughts and input.

KC_Jones

Nope that isn’t correct.

The header needs to be riser, riser, system takeoff(s), then equalizer.  You have combined a system riser and the equalizer.  Also, should have some 15” from the last riser to the first system takeoff as shown in the layout.

pedmec

the instructions are minimum standards for installations. if you have a problem with your system after installation and it you didn't follow the manufacturers installations where would you start to correct the system. Incorrect near boiler piping almost always causes problems in the system, not at the boiler.

mattmia2

bring both risers up to a 90, bring the 90's in to a 90 on the right, tee on the left, 90 out of the tee to a 90 in to the piece of the header with the 2 risers to the steam mains at the back and pitch it all toward the equalizer. Make a clockwise u that starts at the right front corner of the boiler and ends at the equalizer at the right rear. Make all the pieces at least the min in the manual.

109A_5

Hello @Knave72,
It probably should look more like this, except both risers out of the boiler are the same basic height so where the Right riser Tees into the header it is a horizontal Tee rather than vertical one as it appears in your picture that I edited. Probably the right riser will be a little bit longer than the left to get the pitch correct. It needs to be pitched correctly so all horizontal pipes drain into the equalizer pipe. Often the header is one pipe size greater than the risers.

A drop header may be better for even drier steam. Although more materials cost and maybe more assembly time.

EBEBRATT-Ed

@109A_5

That's not right either. The risers from the boiler need to enter the header from the side or the top not from the bottom. Any water coming up your left hand riser will go down the right riser and kill the steam coming up that riser

Knave72

Thanks for all the comments - such a great an helpful community...

And just for the record, when I said "my install" what I really meant is the install I inherited when I bought the house... this is my first experience with steam and its been interesting and frustrating and occasionally rewarding.

@mattmia2 - your description makes me a little dizzy. I'll try and draw up my interpretation and see if I'm reading it right! Thanks for the post.

Knave72

The risers and takeoffs are all "in plane" which makes things like a drop riser or even horizontal tee's more difficult.

The question then is, where should I start changing directions? Ideally I would leave the header, takeoffs and equalizer where they are (although I could adjust the height as needed).

As the risers come out of the boiler can I elbow them 90 degrees at some point towards the front...like this:

ratio

What software are you using to draw those diagrams?

KC_Jones

I'll give you an opinion you might not like. I'd be relocating the boiler to get thing out of plane. You have what appears to be some issues with the return piping too, and if you are going to break into everything, it starts making less sense to do all those extra fittings, and more sense to move the boiler.

The original installer placed it base on laziness and doing the piping wrong, the location is causing issues to do it right.

I'm curious about the software as well. I'm a designer by trade and did a layout on mine when I did the install.

Knave72

I'm using Blender for my diagrams... its a tool I'm using for work for 3D visualizations of drones, satellites and rockets and I'm also starting to use it more on home projects. Here is a bath remodel that is in progress:

Knave72

@KC_Jones - see, I love thinking like that. It occurred to me that the installer probably did do that to be lazy, exactly as you said but it didn't occur to me to move it...

Knave72

I think I can probably move the boiler forward about 10" on the current slab thats poured for it and avoid the extra fittings without too much trouble at all.

Also - speaking of lazy, I guess I should go ahead and add in the return lines and get feedback on those too... If I'm going to do it I guess I should do it all right.

109A_5

Hello @Knave72,

This is more like what I was trying to convey in my last post but at least one did not read and / or understand my text.

Probably the right riser will be a little bit longer than the left to get the pitch correct. It needs to be pitched correctly so all horizontal pipes drain into the header and then the equalizer pipe.

Moving the boiler is a better overall idea.

mattmia2

EBEBRATT-Ed said:

@109A_5

That's not right either. The risers from the boiler need to enter the header from the side or the top not from the bottom. Any water coming up your left hand riser will go down the right riser and kill the steam coming up that riser

Also no swing joint across the sections of the boiler.

mattmia2

Knave72 said:

The risers and takeoffs are all "in plane" which makes things like a drop riser or even horizontal tee's more difficult.

The question then is, where should I start changing directions? Ideally I would leave the header, takeoffs and equalizer where they are (although I could adjust the height as needed).

As the risers come out of the boiler can I elbow them 90 degrees at some point towards the front...like this:

Close but make the risers go straight up. Turn the 90's at the top of the risers 180 degrees and connect them together in front if you don't have the clearance to do it behind.

mattmia2

Knave72 said:

I think I can probably move the boiler forward about 10" on the current slab thats poured for it and avoid the extra fittings without too much trouble at all.

Also - speaking of lazy, I guess I should go ahead and add in the return lines and get feedback on those too... If I'm going to do it I guess I should do it all right.

The header must be in this order so the water works its way to the equalizer:
Supply riser
Supply riser
main connection 1
main connection 2
equalizer

The main connections must be individual. IF there are any pieces of piping from old boilers up there get rid of it and connect directly straight up or at an angle in to the mains. If it is counterflow, the condensate flows back toward the supply at the boiler instead of to returns at the far end, make sure there are drips off of the mains before they drop down in to the header.

Knave72

@mattmia2 The reason I can't take the risers straight up it that they would run into the header and mains...


But moving the boiler seems like the best way to solve that particular problem.

Knave72

@mattmia2 - can you elaborate on this?

"make sure there are drips off of the mains before they drop down in to the header"

Not sure what a drip is... other than what I keep cleaning up.

mattmia2

Knave72 said:

@mattmia2 - can you elaborate on this?

"make sure there are drips off of the mains before they drop down in to the header"

Not sure what a drip is... other than what I keep cleaning up.

The condensate from the system has to get back to the boiler somehow. The mains need to be pitched to allow that to happen. If they pitch to the far end then the condensate needs to go to a return there. If they pitch toward the boiler(or some portion thereof does) then there needs to be a tee pointing down out of the bottom of the main that connects to a smaller pipe that connects to the returns below the water line. That pipe is called a drip.


If the boiler supply is directly under the mains you either need to move the boiler or bring the risers up on a bit of an angle and then still either connect in to the side of the top of the header. Or use a drop header.

The risers could come up on an angle and loop up and drop down in to a tee on the header which i guess is technically a small drop header.

The 90's in the riser the way you have drawn it will trap water in the horizontal sections and interfere with steam and water separating as it rises out of the boiler.

However you pipe it you need a swing joint, at least one of the risers connecting in to a 90 perpendicular to the width of the boiler sections so as the boiler expands and contracts that 90 can turn ever so slightly.

mattmia2

Looking at your other post, what is that device in your return with the 6 bolts holding it together?

This is 2 pipe, right?

Knave72

@mattmia2 - great ideas... I feel I'm at a huge disadvantage with only one poorly installed system to learn from so far. Angling up and slightly forward along with shifting the boiler forward a few inches will give me plenty of room to create that drop header.

That device is a Hoffman F&T trap. I replaced every other trap at the radiators and I'm sure they all stopped working before I was born. They were so incredibly corroded on the inside and something (a date stamp maybe) led me to believe they may have been original to the system.

It is a two pipe system and all the radiators had air valves installed (which I removed).

And message received on making sure there is sufficient pitch to move any water forward wherever it is in the system. Given how many of you have made that comment I'm guessing its a common problem.

mattmia2

Knave72 said:

And message received on making sure there is sufficient pitch to move any water forward wherever it is in the system. Given how many of you have made that comment I'm guessing its a common problem.

Not only pitch, but if the condensate heads toward the header in the mains, you need a drip to remove it before it gets to the header.

I think that Hoffman trap can be rebuilt but others know more than I do.

Knave72

@mattmia2 - drip...got it. How do I diagnose the need for a drip or do I just add them as a safety measure?

Current thinking...

mattmia2

I think that will work, i'll let the steam experts weigh in on if there is some problem with that or if you need a specific fitting somewhere. you also need tees at one or both of the boiler ports so you can put a skim port there.

The pitch of the mains will tell you where the condensate is going. I would not add a drip just in case, that is a lot of extra piping.

TonKa

Post pictures of your actual piping as it is now up to and including the connections to the mains.

There are people on this forum who have a lot of experience plumbing steam boilers in all sorts of spaces. Maybe one of them can suggest a layout which will simplify the piping without needing to move the boiler.

Knave72

Honestly I think I can angle the pipe without moving the boiler... but my first post has quite a few pictures of my setup:

https://forum.heatinghelp.com/discussion/186966/new-to-steam-major-leak-in-air-vent

bburd

One comment I have not seen addressed above is that the header must usually be at least one size larger than the risers from the boiler, if there are two risers. This is to control the velocity of the steam.

dabrakeman

Look at both of your mains as is. Do they currently pitch away from the boiler or toward the boiler?

Knave72

bburd said:

One comment I have not seen addressed above is that the header must usually be at least one size larger than the risers from the boiler, if there are two risers. This is to control the velocity of the steam.

The instructions at the top don’t indicate that but honestly I think the existing header is larger… it’s wrapped in the insulation and white tape but it looks like it must be larger than all the other pipes. 

I am mildly worried that the insulation could be asbestos. 

TonKa

Knave72 said:

Honestly I think I can angle the pipe without moving the boiler... but my first post has quite a few pictures of my setup: https://forum.heatinghelp.com/discussion/186966/new-to-steam-major-leak-in-air-vent

Wow, I now understand the urge to move the boiler.

What I don't understand is, if the previous installer was going to half-**** it, why didn't they use the other tapping instead? They could have been even lazier and gone straight up. 

Your mild concern about asbestos should be pursued. If it is asbestos (I suspect it isn't; just duct tape over fiberglass), wrapping it in that sticky tape like they did is a rather amateurish remediation and I wouldn't trust it.

FWIW, your other thread says addressing the other problems has quieted things down greatly. You may want to consider not redoing the near boiler piping if it's quiet because any functional gains will probably be insignificant.