Can I Convert a Slant Fin GXH-190 DPZ Boiler to a Hot Water Producing Boiler?

TheRyanKing

Currently, I have a one-pipe steam system with a Slant Fin GXH-190 DPZ boiler. The way the piping was installed there is water hammer and banging constantly and I would like to convert over to hot water hydronic system. I currently have cast iron radiators that I believe will be compatible with hot water. I would like to run pex on the long runs and copper wherever needed on shorter runs. Please let me know, I'm really looking for help, I have my basement completely unfinished right now and I want to get all of the piping done before going ahead and putting in the studs, sheetrock, etc.

SeanBeans

I think many people here would rather try to convince you to stay with steam.. and i dont blame them!

Jamie Hall

as @SeanBeans says... and I'm one of them. The first thing to do, since you have a one pipe steam system, is to look around and find out why there is water hammer and banging. A steam system in good shape simply won't do that -- it's almost completely silent.

To help you get started:

cutout pressure on the boiler. Should not be over 1.5 psi. Cost to adjust, zero. Time, two minutes.

All piping. Check to be sure that it has adequate and continuous slope in the right direction. Use a level for this -- don't depend on your eye. It's not just end to end; you need to check for sags on longer runs. And make sure to check all near level sections. Rehang what needs to be rehung. Cost to fix, minimal (usually). Time -- an afternoon in your unfinished basement with the level, some pipe hanging material, a screwdriver or hammer and a good level.

Evenness of heat. If some rooms are warmer than they need to be, or colder, you may need to adjust or change some of the radiator vents. You also need to install main vents on the steam mains, if you don't have them. This isn't hard -- do it yourself -- but there is the cost of good vents.

Now. That should get your steam system running quietly and evenly.

However, if you really do want to change to hot water heat, you will need all new piping. You also must change all the valves on the radiators and get rid of the vents and add return lines. You must pressure test the radiators; odds are pretty good that some of them will leak and need to be replaced (30 psi for hot water heat puts a lot more stress on them than 1.5 psi for steam!). Your Slant/Fin can be reconfigured for hot water, with all new piping and controls. However, it is a relatively low efficiency boiler, and I would recommend going to a new, higher efficiency unit.

You will gain nothing in terms of fuel use from the change, unless you go to a new high efficiency boiler -- and even then the change will be relatively small, and the return on your investment will be negative.

Steamhead

Agreed. It doesn't need an exorcism, it just needs the right people to fix it. Keep the steam.

KC_Jones

TheRyanKing said:

Currently, I have a one-pipe steam system with a Slant Fin GXH-190 DPZ boiler. The way the piping was installed there is water hammer and banging constantly and I would like to convert over to hot water hydronic system. I currently have cast iron radiators that I believe will be compatible with hot water. I would like to run pex on the long runs and copper wherever needed on shorter runs. Please let me know, I'm really looking for help, I have my basement completely unfinished right now and I want to get all of the piping done before going ahead and putting in the studs, sheetrock, etc.

It would have never been installed like that originally. Either the house has settled and things have moved or someone that doesn't know what they are doing moved pipes around.

As has been said steam is silent when operating correctly. It's very likely to be much cheaper to fix what you have than to rip it out and start over which is what you are proposing.

Sometimes banging or water hammer can be fixed almost for free by adding pipe support and correcting pitch or just fixing the pitch on the rads.

TheRyanKing

The piping was never pitched correctly and the way that the pipe was put in, it is above the window and below the floor joists, so it is sandwiched in between, thus i can not move the pipe up or down to adjust the pitch unless i cut the pipes and redo them

Steamhead

How about posting some pictures?

Also, where are you located? We may know someone near you who can help.

JUGHNE

There are piping systems know as counterflow that slope in what seems to be the "wrong" direction. That reverse flow is compensated for at the boiler originally. It is possible that there was a boiler changeout that ignored the main drips and things got cobbled at that time.
Pictures of boiler, piping near boiler, system pipes and a couple rads. Completely free advice available if we can just look!

TheRyanKing

TheRyanKing

Image 1: Beginning of Return After Last Radiator (It should not be straight down and I believe that was done in order to not cross in front of the door)

Image 2: Main Line Feeding Radiator with 1-1/4'' pipe

Image 3: Boiler Name Plate

Image 4: Radiator 1

Image 5: Main Steam Line Directly Out of Boiler, Branched out Left and Right which I believe is wrong, shouldn't it be going in one direction? Also, notice how the pipe is pointed down immediately forcing steam down straight out of the boiler, don't think that is a good idea.

Image 6: Main Line going above a beam, there is no way water is making it over that beam.

Image 7: Radiator 2

Image 8: Side of Boiler & Hartford Loop

Image 9: Return (since the steam line is branched out both left and right, the return come together and meet before going back into the boiler, i dont know if that is correct either.

TheRyanKing

Also, I live in Queens New York @Steamhead

Steamhead

Doesn't look too bad from here- at least they used the full size of the boiler steam outlet. But the vents are in the wrong place on those two radiators. And the pipe going over the beam should have a smaller pipe going under the beam to deal with the water. I'll bet that's what is causing the banging. If I find a diagram of this I'll post it.

And to find a Steam Man in the NYC area, go here:

https://heatinghelp.com/find-a-contractor/SearchForm?Zip=10019&Radius=30&SecurityID=9868408bc8591d955dfcdb1aed6291d8d9934355&action_doSearch=Search

ChrisJ

@Paul S Is near you.

TheRyanKing

Is it still less work to fix this as opposed to converting to hot water?

SeanBeans

@TheRyanKing definately.

TheRyanKing

How much would something like this cost me to be fixed? I could do it myself but I don't have the time honestly

Jamie Hall

I'm sorry, @TheRyanKing ; we don't talk pricing because it varies so much depending on exactly where you are. None of the fixes are likely to be that difficult, though.

Robert O'Brien

The horizontal nipple on Hartford loop is too long, should be a close nipple. Is the header 2.5"?

Danny Scully

Picture is worth a thousand works right @Steamhead? @EzzyT and I did this. I would send him a private message @TheRyanKing, he services your area.

Steamhead

Bingo!

@Erin Holohan Haskell , that needs to go in the Steam Piping section of the main site.

DanHolohan

Nice job, Danny. Looks just like the pic on page 95 of "Lost Art." Old-school stuff!

STEVEusaPA

I would love to be a fly on the wall when an uniformed person sees that in the basement and declares "...A-Ha! There's your problem..."

DanHolohan

Me, too, Steve. ;-)

Canucker

STEVEusaPA said:

I would love to be a fly on the wall when an uniformed person sees that in the basement and declares "...A-Ha! There's your problem..."

Maybe a copy of pg. 95 should be attached to it?

DanHolohan

Erin's on it.

ChrisJ

A laminated sign that says "If you don't know what this is you have no business working on a steam heat system"

Erin Holohan Haskell

Steamhead said:

Bingo!

@Erin Holohan Haskell , that needs to go in the Steam Piping section of the main site.

Here you go: https://heatinghelp.com/systems-help-center/piping-past-obstructions-in-one-pipe-steam-heating-systems/ Nice work, @Danny Scully and @EzzyT

DanHolohan

And nice work Erin!

JUGHNE

Looking at the beam jump picture.....are we certain the steam is coming from the left?? Just a dumb question probably with a "Duh" answer.

DanHolohan

Yes, from the left.

JUGHNE

This is another take for over and under. It is a dry return from the F&T of a hanging unit. The air venting would have been done in the basement thru the cond pump. I don't know why it wasn't just all run over the door as the heater was much higher. This area has been demoed. No pictures. From a print of a 1955 school house..the original Kewanee is still firing. Shows that ME's put these details on a print. FWIW

Note: feel free to use the example.....it was drawn and installed by Dead Men....though they might have put CO on the lower wet return tees?

jumper

ChrisJ said:

A laminated sign that says "If you don't know what this is you have no business working on a steam heat system"

I've tried that. Put sign on stuff stating not to modify without calling me. I've also added notes to plans stating that the detail supersedes code. That can get one into trouble. Even if a code is written years after the project a proscription is meat for lawyers.

Paul S_3

This is a over under piping I recently did....i repiped a steam main and had to go around a window.... thanks @ChrisJ ..... @TheRyanKing you can private message me, I service the 5 boroughs of Nyc....