Webster sylphon traps 02h

kevsul1

I’m working at a 3story school that has an old steam system my problem is on the first floor there are 5 radiator on one side of the building in a row that aren’t heating the main supply line is hot but I don’t have heat going up the supply to the radiator each radiator has a Webster trap on the condensate line when I take them apart they aren’t clogged with debris I can blow though them I blew nitrogen through on thinking it might be clogged I get free flow from one side to the other I bumped the pressure on the boiler to 3-5 and the two closest to the boiler starting getting hot but not as hot as the others I’m a little I’m a little at a loss it seems it has to be a restriction somewhere suggestions would be much obliged

kevsul1

Also there is no thermostatic valve on the supply that would be stuck closed

Grallert

contact Tunstall they should have replacement elements for those traps. It's very unlikely that increasing the pressure will be any benefit. In fact the opposite is true. Pictures?

kevsul1

Why would it have an opposite effect? I took a few of these traps apart there isn’t anything blocking them (sediment or dirt) I can blow through them makes me think it’s not the trap??

Grallert

https://heatinghelp.com/systems-help-center/steam-velocity/
The traps are failed open most likely so yes blowing through them you'll find no blockage. That also means that there is no pressure difference across the trap so the steam can't move through them. Traps will more often fail open in my experience causing hammer and unbalanced heating, often in what would seem like unrelated radiators.

JUGHNE

I would guess you are not passing air thru the rads and then thru the traps. Raising the pressure will move the steam a little by compressing the air more.
It is unlikely that 5 traps on one main would fail shut.

Follow the condensate line, there may be a F&T at the end that has failed or is plugged with sludge or both.

As an air test you could just leave a trap cap loose and turn the steam on for that rad. Be ready to tighten it when the steam comes to the trap.

As old schools go the F&T may be hiding some where and has not been touched for years.
I did a school from 1932 and some trap elements had the 1931 date code on them. For that case all the trap elements were removed and orifices installed in the supply valves.
Main air vents were added ahead of the F&T's to speed up steam delivery.

Let us know what you find.

kevsul1

It’s weird there are some rads on that condensate line that are getting hot and working fine but some aren’t I’m going back Friday with some new traps hopefully the new traps will resolve the issue

JUGHNE

On the 5 that do not work is the trap itself getting hot?

It is possible that one or more of the hot rads has a bad trap that allows steam into the return and closed the 5 traps of the cold rads.

Perhaps it is possible to fix the wrong traps.

kevsul1

Yes they are I get steam out of the condensate return line when I take the trap off the line

JUGHNE

If all traps work correctly, they should "trap" the steam from getting into the return line. That steam could be coming from any failed rad trap(s) connected on that line.
That failed trap somewhere else can pass enough steam to close other good traps and often wreck them.
Have you simply taken the tops off to see the element inside?

JUGHNE

If you change the entire trap assembly you will most likely have to change the spud going into the radiator. This can lead to a fair more amount of work and grief. IIWM I would just open the cap and replace the elements.
For those traps I used a socket of the exact size with an impact wrench. Works like a champ and worth any investment you make for tools.
Then a socket to remove the trap element.....check the date code.
It may be worthwhile to change all the elements on that line if the date code shows 10 years or so old. Or you can guess which ones are bad and just change those but that would be rather time consuming and you risk wrecking any new ones you just installed. IMO
I got my replacement elements thru Barnes & Jones because that was the connection my supplier had. The replacement was such that the original trap cap could be reused.....not always the case.
Tunstall would also have something I'm sure.

kevsul1

Turns out there is an actuating valve on the steam line for that side of the building just happened to look up in the chase and saw it 🤦🏻‍♂️🤦🏻‍♂️ Opened valve good to go thank you guys for your help I appreciate it

EricBaisch

I have the same system. It sounds like you figured it out, but for future reference the crossover trap to the dry return at the end of the steam main and the main vent at the end of the dry return near the boiler need to be working as well. Also, too many failed traps will cause issues at the end of a long cycle if the boiler is oversized for the radiation being used.