I'm convinced that my pressure gauge and pressuretrol aren't getting a proper reading.

Jay__Low

Moved into a century-old home with a boiler and steam radiators a few weeks ago and knew the radiators had some minor issues. Some of the vents just didn't work, and some of the valves had been painted over. I replaced what I needed replaced, got to know the system inside and out, but one thing still bothered me... the pressure gauge and pressuretrol. They're connected to the same pigtail coming out of the steam side of the boiler (pictures attached).

The pressure gauge always reads somewhere between about 3.5 and 4 psi, never outside of this range. Even when I bring the system down to a total cool, or when I know the pressure is getting maxed out.

The pressuretrol also seems to be receiving this same (assumedly) incorrect pressure reading, because I can set the cut-in pressure to 0.5 or 1 or 1.5 and the system will never kick in, again even when it's allowed to come to a complete cool. It only operates at a minimum cut-in temperature of around 2 or a bit higher. The differential (additive) is set to just higher than 1.

So, I'm kind of at a loss. When the heat runs for more than 15-20 minutes or so, some valves start sputtering once all the vents close off. I assume this is telling me that the pressure is starting to build out of control even though my pressure gauge still reads 4.

I want [need] to get the pressure down to 0.5-1.5 -- this is a small house and there's absolutely no way that what's happening is normal.

So I guess the problem is in the pigtail. What are the chances there's a blockage in there? Or could it be some other issue that I'm not thinking of? I know it's not *just* the pressure gauge, because the pressuretrol seems to be operating relatively consistently with it. Let me know what you think.

Jamie Hall

If that iron pigtail isn't blocked, it would be amazing. On the other hand, that 0 to 30 psi gauge is there to keep the insurance and building inspector people happy. They are rarely reliable.

So... Step one is to remove the pigtail and make sure it, and the opening into the boiler-- is clear. This may be harder than it sounds, as I see that there isn't enough clearance to take the pressuretrol and pressure gauges off easily -- and I'm not convinced from the picture to spin the whole assembly. Once you get it all apart, as I say make sure it's clear. Better yet, replace the pigtail with a new brass one. When you put it all back together, add some unions and another T and a couple of elbows and nipples and rebuild the thing adding a 0 to 3 psi gauge to the assembly.

Jay__Low

There's a little more clearance than it appears in the first couple photos (overhead shown below). I think the first thing I'll do is just take off the pressure gauge, hopefully discover and unblock the blockage, and replace it with a gauge with a more reasonable range. If the blockage seems awful then I'll work on taking the whole thing apart and replacing with copper.

JUGHNE

IIWM, I would power the boiler down and then would unhook the wires from the control.
Using a hammer handle or such, stick your lever thru the pigtail loop from the right.
Loosen, unscrew the pigtail enough so as to break the threaded bond.
Then saw the iron pigtail off somewhere that you can then rotate the remains of the pigtail out of the boiler.

It would be best to get a 2-3" nipple--tee--clean out plug--4-6" riser pipe and then coupling to a brass/copper stand up straight pigtail...then a tee and fittings to assemble every above the top of the boiler where everything can be rotated for assembly.
Use 1/4" brass or SS for everything.
Add another tee/port for a 1-5 PSI gauge.
Check the bottom of the control and gauge for sludge.

Jamie Hall

I think I'd go the way @JUGHNE suggests -- but I'd make sure I didn't need heat for a few days! Although if things go well the whole job needn't take more than a couple of hours, if you have the bits and pieces on hand when you start. As he implies, you need to keep the 0 to 30 gauge, and add the 0 to 5 gauge -- not replace.

Jay__Low

Well, when we tried to unscrew the pigtail from the tank, it started spinning, and then this happened. There was indeed a rock-like blockage of the entire passage, and it broke off right at the tank. 

We just bought a hammer-in pipe extractor kit and are ready to try and extract it, but I'm here to ask if this is a good idea or if we should call a professional at this point. I don't want to damage the tank.

JUGHNE

Curses! and other words.

That does not look like it is screwed into a larger bushing as most of them are.

I would get a 1/4" pipe thread tap and some form of Tee handle, often a socket and ratchet will work.

I would then try the extractor.

If that fails then mini-hack saw blades to cut 2 or 3 times across the broken threads.
Avoid cutting the boiler female threads...slow and tedious...black tape around the blade for handle.
Then small chisel or pick may cave in the sections of your 3 slice pie for removal.

Then run your tap thru to clean up the threads.
Tape and pipe dope both recommended on new part going into the boiler.

Good Luck.

(But now you know the P-tail was plugged and the problem)

Jay__Low

Thank you. At this point it's above my pay grade so I'm calling a plumber -- he scared me a bit when he said this might require a new boiler after I described the problem to him. Personally I don't think it's that awful? I don't know why this would necessitate an entirely new boiler. Worst comes to worst, we plug up that hole and install the pressure gauge elsewhere on the steam side.

JUGHNE

Assuming that is not screwed into a bushing which could be removed, then the existing opening could be drilled larger and a 3/8" pipe tap used to thread to the next size.

New boiler would be like buying a new car if one bolt stripped off of the engine. IMO

Jay__Low

That's what I figured. There are solutions that are above my pay grade but at the end of the day, this is just connected to the control portion and will be operating at a very low pressure. It can handle a little finagling.

EBEBRATT-Ed

@Jay_Low

Don't let the plumber or anyone else talk you into a new boiler.

Check"find a contractor " on this site and post your location. Someone may know someone in your area

Jay__Low

Thank you for all the reassurance, guys. It seriously means the world right now. I am located in North Jersey (Morris County area). 

LS123

use a contractor from heatinghelp.com that work with steam. Below is the link to contractors.

https://heatinghelp.com/find-a-contractor/

Jamie Hall

Or if you're feeling lazy -- PM @EzzyT or @clammy

EzzyT

@Jay_Low you can reach me at 2018878856
That Utica boiler has a 1/4” tapping for the pressure gauge and pressuretrol.
Based on the picture you posted it looks like the broken piece of the pigtail just needs to be removed a tap ran through it and a new pigtail installed.

mikeg2015

EzzyT said:

@Jay_Low you can reach me at 2018878856
That Utica boiler has a 1/4” tapping for the pressure gauge and pressuretrol.
Based on the picture you posted it looks like the broken piece of the pigtail just needs to be removed a tap ran through it and a new pigtail installed.

Exactly. New boiler…pffft. Whatever. Worst case drill it out to 1/2” NPT and retap. If you work on steam you should have a 1/8, 1/4, 1/2 and 3/4” tap on hand.

Hell, in a pinch I’ve added aux main vents to elbows and gotten long laterals to work adding a varivent to a fitting near the end of the run. Just drill and tap. Lots of tape if its a little thin.