Sticking pressuretrol?

Jeffrs

Hello, I appreciate all the help from everyone since I've posted a few times recently. I'm trying to put everything together with my system to be certain everything's running the way it should.

So when I moved in this past October, the boiler wouldn't even light. I spent time studying the wiring diagram and confirming that the pressuretrol wasn't closing the circuit to allow for ignition. Anyhow when I was troubleshooting back then, when I removed the cover to the pressuretrol to check for 24VDC to and thru the pressuretrol, it unstuck and lit. Now aside from high fuel bills the system does heat and seems to work relatively smoothly. Cut-in is set to .5 and its differential is at the lowest setting of 1. So that means my cutout should be at 1 psi correct?

Reading some articles online, it appears that the boiler should run up to pressure and shutdown at cutout and refire at cut in if the thermostat is still calling for heat. Well mine never shuts down. It runs the whole time until the thermostat is satisfied. The gauge never budges off the stop either. Does this sound like a pressuretrol that is stuck closing the circuit? Or a clogged pig tail?

Thank you guys tons

BobC

it depends

If the boiler and the system are well matched you might never see appreciable pressure unless you are coming off a deep setback or it's really cold out. Your chance of seeing pressure on a 0-30 gauge is not good, think about adding a 0-3 PSI auxiliary gauge so you can see what's going on. make sure the pigtail is between the gauge and the boiler.



If I remember right you checked the pigtail this fall so the pigtail and the pressuretrol might be ok. If you add the 0-3 you can check the pigtail when you pipe it in.



Bob

Hap_Hazzard

Pressuretrol

The cut-out pressure is the sum of the cut-in and the differential, so yours is 1.5 psi, right where it should be.



If the pressuretrol isn't working, a plugged pigtail is the most likely cause. If your pigtail is steel (if you can't tell from the rust, test it with a magnet) it's a good bet that it is plugged. Don't even try un-plugging it; just get yourself a new one made of brass. If you can't find one locally, there are lots of online sources. You just need to get the same type, i.e. straight (360°) or right angle (270°). Use ptfe tape on the threads and remember to put water in it.

Jeffrs

Yep it's brass

It's brass. I took the pressuretrol and gauge off. Tons of black crud in the the tee that I pulled out. I blew into the pigtail while its still installed in the boiler. Kinda tough but does allow air thru, however it did seem possibly clogged. I should probably remove it and check for clear passage but being 10pm and if I bust it off ill be without heat for the night and a wife ready burst. In any case just for now, does it make sense for it to be tough to blow into while still attached to the boiler? I have no main vents, yet ( my next project ) so I'm sure the pressure I'm blowing in has to go somewhere.

Thanks again all

Hap_Hazzard

Blowing in the pigtail.

Unless the system is heating, all your vents should be open, so there should be no resistance to blowing through the pigtail, and I think you'd know if the system was on. ;-)



Tomorrow you can take that pigtail off and rap it on a hard, flat surface. I use the top of my head, but you might prefer your basement floor. If you have any of those wire tube brushes, they can help, but I have yet to see one that will go all the way through. Knock out as much as you can but try not to put any dents in it, then blow it out with a blow-gun, if you have a compressor, or use a shop-vac to suck the loose stuff out, then soak it in some washing soda or white vinegar for an hour or two and rinse it out.

Jeffrs

Nope not on

Heh nope heat wasn't running. But again I have no main vents at all so when I blow into it I have to blow thru all the plumbing up till the closest radiator vent. In any case, how do I remove? I see a hex nipple recessed into the boiler outter housing which I would not be able to get a wrench on without removing part of the outter panel, which would require the removal of other components such as sight glass, Low water cutoff. I know it's brass but I see that it's threaded on the end. Should I be able to pipe wrench it gently off the nipple?

Also, dumb question but can I Teflon tape all these fittings when going back together? Everything's pipe doped and I'd prefer not to use it if possible so I don't get boiler water contamination later on.

Thanks again. Much appreciate the help and the kind responses.

Oh and earlier you said if I were to put a pigtail on to use ptfe tape and then put water in it. What did you mean put water in it? Sorry probably a dumb question.

nicholas bonham-carter

No dumb questions here

The only way to learn is to ask, and no one here will ever complain about a dumb question. We were all without steam knowledge before we came here, except for the real pros who have got the ball rolling in the beginning.

A good low pressure gauge would be essential for diagnostics, (gauge store.com--0-3 psi, graduated in ounces). Then you will know what your pressuretrol is doing. In addition, you will see if your main venting is doing the job, or if the fuel company is charging extra to remove the air from your system.--NBC

Hap_Hazzard

Pigtail R&R

Usually the loop of the pigtail will give you enough leverage to turn it by hand, but if the pipe joint compound has hardened, you might be in for a tough time.



The trouble with using a pipe wrench on a brass pigtail is that brass is soft and pigtails are thin-walled, so the wrench is apt to crush it. If that happens you'll have a hard time getting it out because the crushed tubing will just twist right off.



You might be able to get more leverage by sticking something through the loop, like a large pipe or a baseball bat. The bigger it is the better. You want to apply the pressure to the largest possible area. If it doesn't seem to want to come out without a fight, stop and wait to see if any of the pros have any tricks you can use. Don't do anything drastic unless you have a new pigtail and a 1/4" tap on hand.



And yes, you can use ptfe tape on these. If the last guy had done so, you'd be having a much easier time right now.

will smith_4

Pigtails and pressuretrols

You don't need a pigtail for p-trols/gages if you do a little manifold that drops down a bit to provide a water seal. If your ptrol is a mercury switch, you have to make sure it is oriented properly in relation to the pigtail, and you also have to make sure it's level. That doesn't matter if it's the newer honeywell mechanical switch-but I'd rather have the old mercury switch anyday-I've seen plenty of problems with the new switches not working properly.

BobC

Pigtail removal

I've used Jorgenson clamps to remove pigtails that seemed impossible to budge, the large contact area offers a good chance of success. The only problem is you need room to work with them.



Bob

Hap_Hazzard

I assume you mean the wood clamps.

Jorgensen makes all kinds of clamps. Nice vises too.



You could probably also use a big adjustable wrench on it with a couple of shims to protect the tubing.

Jeffrs

Thanks everyone

I haven't removed the pig tail yet but I will. I appreciate all the suggestions. I know the pigtail isn't completely clogged. Whether there's an obstruction still existing in the pigtail I'm not sure yet, but I will be soon. As for the gauge suggestion, where can find a 0-3 or 0-5 psi gauge, and how much can I expect to lay for a gauge?

Thank you again

Hap_Hazzard

Gauge sources

http://www.valworx.com/category/gaugestore

http://www.coleparmer.com/Search/low%20pressure%20gauge