Pressuretrol won't shut off

JeremyN

We recently moved into a new house with steam heat.  I'm really new at all this but have been reading this site for the past few days and am getting to know some of the basics. 



As heating season has just started, we recently fired everything up for its first extended run.  As I went downstairs into the boiler room, I noticed that there was quite a bit of steam leaking from the #77 ventrite valve on the wet return line.  I shut down the boiler, but before doing so noticed that the pressure gauge was reading between 4-5 PSI.  I looked at the Pressuretrol and it was at its lowest setting.  I opened it up, and the differential was set to 2.  I backed this off to 1 and restarted things.  Even with the new setting, the system still reached over 4 PSI.  From the settings I would have expected it to cut out at 1.5.  I am able to manually trigger the cutout so it's at least working, but I'm wondering why it might not be responding correctly to the pressure rise.  It is mounted on a T off the same pigtail as the pressure gauge. 



Any thoughts on what might be the problem?  I actually went a step further tonight and completely disconnected the spring from the pressuretrol to make the cut in as low as possible.  Still hits 4+PSI without shutting off.  Could something be clogged or dirty?  Does the pressuretrol just need replacement?  If so, is it worth just going to a Vaporstat instead? 



Also, is it normal for the main vent to blow off steam at higher pressures?  I took it apart and cleaned it but it still seems to do it.  The mechanism seems dead simple, so I don't really know how anything could be wrong.  One thing I noticed is that the gasket is pretty shredded.  Steam seems to be leaking around the collar in addition to the top.  Perhaps a gasket replacement would help.  I'm not sure where to get just the gasket though and the seemingly simple part seems to cost around $100!  I'm hoping to avoid a new one if possible. 



Thanks for reading and any insight you guys may be able to provide.  This site has been super helpful so far.



Jeremy

JStar

RE

The pigtail needs to be cleaned. It's probably blocked up, preventing the pressuretrol from working properly.



The main vents will start to leak at higher pressures. Sometimes they hiss steam, other times they shoot water. Now would be a good time to replace them. You can go to a local supply house and ask for Gorton main vents. They should be a little easier on the wallet, and work very well.

JeremyN

Thanks JStar

I did try briefly to remove the pigtail last night, but I stopped when I felt like I was applying to much torque.  I didn't want to end up breaking anything.  I tried the same with the pressuretrol with similar results.  Any tips on getting these off in a safe way? 



Also I've noticed that the water in my site glass is a very dirty brown color.  This seems to have happened after my annual maintenance - I hadn't noticed it before.  Could this be part of the problem I'm observing with the pressuretrol?



Jeremy

04090

help

I recently had the same probem with a pressuretrol.  Cleaning out the pigtail and flushing it with lots of water made a world of difference.  Instead of sounding like a supercharged V12, the boiler merrily idles along under the control of the pressuretrol like a VW engine.



Mine was stuck and I applied as much pressure as comfortable with at the base of the thread with a pipe wrench.  The tail loosened immediatly when I used a 3' pipe wedged between the loop.  Took very little pressure; not that I would have used much more than that.



Posting this just in case it helps you. 



(My wife was furious that the ink like muck in the pigtail stained her shiny porcelin sink, but she's a happy camper now.  Just a warning, it might be full of potent stuff.)

JeremyN

Got it!

I managed to get the pigtail off last night.  Turns out I was trying to turn the nut the pigtail was screwed into rather than the pigtail itself... once I figured out I was being an idiot, it came off remarkably easily.



After taking off the pressuretrol it turns out that the port leading into it was completely scaled over.  I had to second guess myself before breaking it as it was so complete that it almost looked like it belonged there! 



After giving everything a thorough cleaning and reassembling, I 'm happy to say that everything is working fine.  The pressuretrol cuts out at about 2 or so PSI.  It's a bit higher than I'd like, but I guess to get finer control, I'd have to go to a vaporstat.



Thanks for the advice!

Rod

Main Vents

Hi - Glad to hear you got your problem fixed. The high pressure has probably destroyed your main vents and besides, replacing them with Gortons which have a greater venting capacity should make your system operate better. For more on venting you might want to visit Gerry Gill's website.Gerry's a Cleveland steam pro who wrote of book on venting. http://www.gwgillplumbingandheating.com/webapp/GetPage?pid=415

You might also want to take a look at the steam books in the Shop section of this website. A very good one to start out on is "We Got Steam Heat!"

http://www.heatinghelp.com/products/Steam-Heating-Books/25/61/We-Got-Steam-Heat-A-Homeowners-Guide-to-Peaceful-Coexistence

- Rod