Vapor/vacuum system?

conpro

I need some help.

In my area of the country, there are very few steam systems and almost all of them are one-pipe basic steam systems.  However, I was asked to replace a customer's steam boiler today and when I went to assess the job, I found a strange box near the boiler.  It is a Hoffman boiler return trap.  Along with this I also found a float vent/air eliminator.  The rads are two pipe with the Hoffman #17a trap. 

Am I looking at a vapor/vacuum system, and if so, should I not attempt to replace the boiler as I may be 'married' to a lot of problems in the future?

Let me know what your opinions are.  Thanks                  Curt

Pumpguy

What...

is your area of the country?  Just curious.  Someone close to you may be a good source of help.

Jamie Hall

Probably is

or was a Hoffmann Equipped vapour system.  It may not even have been too badly knuckleheaded, if the boiler return trap and the corresponding float vent air eliminator are still there and hooked up.



Hoffmann -- and most vapour systems -- are darn near bullet proof, provided only that they are not mangled.  There is some very good information on them in both the systems and resources areas of this site.  Worth looking at.



They are certainly not problems.  There are, however, a few pretty basic things to keep in mind. 



First off, when you replace the boiler, make sure that the water level in the new boiler is the same as that in the old one, within an inch or two.  Too high may give you wet steam problems.  Too low is very likely to give you a whole host of problems which may be very hard to track down, never mind solve.  It's easy to avoid them, but you do need to think about it.



Also remember that the boiler manufacturer's piping recommendations are an absolute minimum.  Don't cheat.



Second, vapour systems -- like this one -- work on very low pressures.  Half a pound (8 ounces) per square inch or less.  Anything over that and they won't work well, if they work at all.  Again, the soloution is simple: put a vapoustat on the boiler in addition to the safety pressuretrol (I would suggest starting with the vapourstat cutout at 8 ounces with a 6 ounce differential, and the safety pressuretrol at, say 3 psi cutout).



Third, you may find that some of the radiator traps need to be replaced, particularly if the system pressure has been too high.  This is usually not a difficult job; there are drop in replacements available for the innards.



Fourth, you may find that the venting has been messed with.  These systems vented at the boiler, and used crossover traps from the steam mains to the dry returns.  Those crossover traps (which are the same as radiator traps) need to be checked and functional.  If it should turn out that the original venting doesn't work -- it could happen -- you can use conventional main vents at the boiler instead, or in addition.



So, bottom line is you shouldn't find yourself "married to a lot of problems" in the future, provided you install the boiler right in the first place and take the time to make sure everything else is right, too.

Charlie from wmass

If you are In CT or MA

Give them my name and number. I would be happy to enter wedded bliss with another Hoffman.

Noel

Jamie nailed it.

But he has one, too. He still has the coal fired gravity warm air furnace (unconverted octopus) right beside it, that it replaced, and a bin with coal in it, still.



Yankees. Gotta love us.



Noel

steamychick

picture?

Jamie, any chance on getting a pic of that old coal fired furnace? My house originally probably had something similar, but alas, it's long gone. :-(

pipeking

THREADJACKING....

 STEAMYCHICK has only been on here for a few day and already has a steam heated chair!!! u don't beleive me? look at her avatar!

steamychick

Sorry!

didn't mean to thread jack! (BTW, a friend sent the avatar pic to me as a joke about my rads, thought it was neat. sorry.)

Jamie Hall

Don't worry...

about hijacking threads.  Everybody does it all the time...



I suppose I should take a picture of that octopus of a warm air funace and post it.  I don't think I have one!

pipeking

NO,NO,NO, NOT U

 I am threadjacking! i seen your avi and had to bring it up. your avi can't threadjack, it's a chair, chairs don't talk!!

steamychick

oops...

my mistake. I took it wrong,sorry about that. thought you were busting on my avatar. but since you're not, being the pipeking, i expect you to start on a matching sofa a.s.a.p.! :-)

(now we probably are threadjacking...) lol

Noel

pictures

Here's the octupus...

Jamie Hall

Good heavens, Noel!

Where did you find those?

Noel

In your basement...

There is also a funny looking header from an old boiler down there on a #2 Hoffman system, if I recall correctly.

Jamie Hall

There is

It's still there -- now hooked up with a rather fancy piping arrangement to a nice big drop header which Charles Garrity welded up for me.  Works splendidly.  You should come by again some day and see!



For that matter -- that pretty much applies to any Wally...