Repiping a Columbia

Steamhead

This Columbia was recently installed on a Hoffman Vapor system with a Return Trap and Air Trap. The owner complained of constant banging, which in one case apparently damaged a runout to a radiator. The installers repiped it twice, and replaced all the steam traps they could find, with no improvement.

Here's what we found when we got there- a 4-inch header fed from two 2-inch steam outlets merging into a single 2-inch pipe. Can you say "Wet Steam"?

Steamhead

We built a new drop header with a rather unusual configuration, due to the existing header configuration. The existing header was off-pitch, so we added some more straps and used the left-hand riser from the boiler as a locator. The right-hand riser has a scissors-type expansion joint which will allow the header to move with expansion. Two 2-inch risers drop into a new 3-inch header which elbows into the existing 4-inch header.

The new 4x3 reducing elbow locked up in the wrong place, so we had to heat it to bring it into position.









Guess what? No more banging!

Steamhead

This Hoffman installation has an end-of-main trap setup that we don't usually see. The mains are dripped and vented through 1" thermostatic traps. The original end-of-main traps were Hoffman #10A, which appear to have roughly the same throughput as a Big Mouth crossover trap.

The installers had replaced the one end-of-main trap they could see, with a Hoffman #9C. But there was another one hiding behind a paneled enclosure. The owner removed the paneling and we found a 10A. We replaced both of these traps with MEPCO 3C traps, which have the same throughput as the Big Mouth Crossover Traps.

Steamhead

We also installed a Gorton #2 on the air trap, replacing a Hoffman #76, replaced the failed Vaporstat (apparently Vaporstats don't like water hammer) and added a low-pressure gauge.





The system now heats much more quickly, and we don't hear the anvil chorus. Enjoy!

Jamie Hall

Nice! Very nice!

SeanBeans

Hey @Steamhead what book is that next to the trap?

Gordo

@SeanBeans : That is the 1934 edition of The Hoffman Data Book.

Paul48

I see Waterbury CT on that Hoffman trap. It's amazing how much manufacturing was done in Connecticut. You can still drive through most cities and towns here, and see the remains of the facilities that occupy whole neighborhoods. Sorry for wandering off topic.

SteamCoffee

Wow, nice way of solving what your handed! About when do you think it was originally installed? Great craftsmanship.....

Steamhead

Last year, I believe.

Gordo

@Paul48 : You may find this of interest:

According to the 1934 Databook, page 252,

"The approximate date of manufacture of Hoffman Valves can be determined by the following marking:

Valves marked "Boston"...............1913-1915
Valves marked "Chicago".............1915-1918
Valves marked "New York"..........1919-1920
Valves marked "Waterbury"........1920-1934"

Steamhead

Part 2 is here:

https://forum.heatinghelp.com/discussion/162197/hidden-restriction-in-two-pipe-vapor-steam-radiator

gerry gill

nice troubleshooting guys!

Tim McElwain

It never ceases to amaze me as too hidden controls on all kinds of systems that no one knows about. You sure have to be a detective in this business.

I once had a job with a gas pressure problem eventually found someone had built an addition around part of the gas line which was for the old boiler. New boiler was having a problem with getting enough gas pressure. I found two old regulators in series buried in the wall that had been added during the remodel..

ChrisJ

Tim McElwain said:

It never ceases to amaze me as too hidden controls on all kinds of systems that no one knows about. You sure have to be a detective in this business.

I once had a job with a gas pressure problem eventually found someone had built an addition around part of the gas line which was for the old boiler. New boiler was having a problem with getting enough gas pressure. I found two old regulators in series buried in the wall that had been added during the remodel..

Oh come on, admit it, you were amazed this time. ADMIT IT!

Tim McElwain

I am always amazed at the crazy things we run into in this business. Then of course there are the people we meet, they always amaze me.