some help/advice, pressure shut off, pigtail

eegad

20 years ago I moved into a small house built in 1950. One pipe steam heat. Ancient yellow Burnham heating chamber, Beckett model AFG burner, Honeywell R7284 primary control (which was replaced ~15 years ago). Once a year I have someone come and do the "annual startup/cleaning service" as part of my oil contract. I check the water level once a week when I do laundry, fill as needed, and drain out and replace some dirty water every few weeks. Other than failure to ignite now and then, requiring me to go down and hold the reset switch a few seconds, it just plain works and keeps me warm through the winter.

Got me through last winter fine and I shut the main switch off in late April. But then we had a very rare chilly memorial day weekend here in NJ, so I turned it back on one morning for a quick dose of heat. Normally when the system is completely cold like that, I know it takes maybe 45 minutes or so to run through the first cycle and for all radiators to get warm, at which point it shuts down for 5-10 minutes before coming back on until the thermostat temp is reached. But this time I was sitting in the room above it and after an hour I started to think "it's been running a long time". Then the radiator started hissing, which it normally never does. So I went downstairs and saw the 0-30psi gauge on top was around 12lbs. Now, I never really paid attention to it before, but I kinda think it only ever got around to a few lbs before shutting off. So I flipped the main switch and forced it to shut off. By then the house had warmed up anyway.

If it was mid winter I would just call for service, but since i won't need it again for another 4 months, I decided to maybe see if I could diagnose and fix it myself. I'm no great handyman, but I can replace a faucet or the innards of a toilet, or take apart the dryer and replace the belt. Basic stuff. So I googled a little bit about how the system works.

The pressure shut off is an oil-o-matic 'type 400', I assume the same thing as a basic honeywell "pressuretrol". I tried doing the following today :

Completely drained the tank. Removed the panels from the pressuretrol, and the low water cutoff, loosened and retightened the wires. Same with wires from thermostat. Put water back in tank. Turned up thermostat and flipped main power switch on. It fired up. With panels still off, I then used a wooden popsicle stick to carefully press up on the metal plate at the bottom of the pressuretrol. The system shut down. When I let go, it restarted after a few seconds. Same with lifting the little mercury filled bulb in the low water cutoff. So I seems as if all wiring/switches work fine. Shut main switch off.

I read about the pigtails getting plugged up which seems to me the most likely thing, so I figured I'd next clean that out. I disconnected the wires and removed the pressuretrol. I then tried to snake through the pigtail with both a small pipe cleaner and a long heavy ziptie. Neither would get further than the bottom of the pigtail ring.

Tried (with hands) to unscrew the pigtail, but it's not budging. Is there a trick to it? Should I try soaking it with liquid wrench or something? Thoughts/suggestions? Or should I stop messing with it before I make it worse and just call someone to deal with towards the end of the summer?

mattmia2

You can use something like a screwdriver or small pry bar or piece of pipe as a lever through the curl of the pigtail to turn it, try the lever with one hand and support the back of the pigtail with the other so it turns at the base instead of trying to bend it at the base or there is some possibility you could break it off of the lwco housing.

The blowdown you should be doing should be at the valve at the bottom of the lwco with the boiler firing. It should stop after you let a little water out. That lwco probably should be rebuilt or replaced to make sure it is clean and free to move.

EBEBRATT-Ed

Scrape the pigtail outside with a file or a knife to see if it is brass or steel. Steel will be shiny brite and brass will be yellowish.

If steel it should be replaced with brass.

If it is steel it could be rusted in place and may be difficult to remove and it could break.

Best bet is a small pipe wrench grip it as close to the boiler as possible. If it feels like it will break you may be better off calling for service.

Pigtails plugging up can be a common issue.

Also you should not have to reset your burner that is not normal operation and an indication something is wrong.

mattmia2

If you use a pipe wrench, make sure it is seated so the back of it is against the tube when the jaws grip so it doesn't collapse it. If that lwco hasn't been opened and cleaned in a decade or 4 it should be.

EdTheHeaterMan

Oil Burner service contracts rarely include ALL the necessary maintenance needed for a steam boiler. I used to do those "clean-outs" when I worked on oil burners in the 1970s and 80s. The important thing about the steam boiler is to make sure you have good water quality, the LWCO works and the pressure switch works. Part of that is to be sure the pigtail is not blocked.

Next, every few years, (every year is better but that never seems to happen) you want to flush out the wet returns and the bottom of the boiler. There is a lot of mud that forms at the lower sections of the system that can block the condensate from returning to the boiler. Now testing the limit operation (pressure and low water) and the safety control (with the reset button) are part of the oil burner clean-out… the cleaning of the mud from the bottom of the boiler and the pigtail are not included. The oil company would call that part of the maintenance "a plumbers job", since that kind of work can get involved. It is not included with oil burner that is covered by the service agreement.

That said, Our oil company could do the work if you wanted it done, but there was an extra charge. So that is why it was not recommended every year. Maybe every 3 to 5 years, unless something was discovered that caused a concern, like the LWCO was getting stuck…

When you said "…and drain out and replace some dirty water every few weeks." I hope you mean that you were letting the dirty water out of the LWCO using the valve at the bottom of the triangle. That valve should be open when the burner is operating and there is some small amount of steam pressure. When you open the valve, the burner should stop, the water should flow until clear water is visible, and steam exits the valve. This does 2 things: 1. ensures the LWCO float is not blocked and will turn off the burner if the water gets too low, and 2. prooves the electrical switch works when the burner stops 

I hope this info helps a little

 

EdTheHeaterMan

To get that old pigtail out, you need leverage. Use a piece of 3/4" steel pipe or a large screwdriver

as @mattmia2 mentioned above. If you have a steel pigtail, you may need to heat the base near the LWCO cherry red with a torch. that will break the rusted seal from years of corrosion and rust that has bonded them together.

EBEBRATT-Ed

The farther you grab it from where it screws into the LWCO the more chance it will break off.

retiredguy

I would spray the threads with "Kroil" or any penetrating oil numerous times over a few days before you try to remove that pigtail. Let the penetrating oil sit for hours to allow it to do it's magic. Then use a 6" or 8" Ridgid pipe wrench, putting it as close to the low water control as possible to reduce the chance of breaking the pigtail. Try turning the pigtail just slightly CW as if you are trying to tighten it before you try to remove it. The last torque that pigtail saw was when it was installed so the resistance to turn will be the least when turning it CW as if still tightening it. When you get it out, replace it with a brass pigtail and use Permatex anti seize lubricant.

eegad

Thanks for the replies. Will try soaking it with penetrating oil for a few days and using a pipe as leverage and see what happens. Couple of things...

If that lwco hasn't been opened and cleaned in a decade or 4 it should be.

When you said "…and drain out and replace some dirty water every few weeks." I hope you mean that you were letting the dirty water out of the LWCO using the valve at the bottom of the triangle. That valve should be open when the burner is operating and there is some small amount of steam pressure.

Yes, I drain some water out of the valve at bottom of the lwco, but I don't think I've ever done it while the burner is running. I always wait til an hour or two after it stops. Figured it was better to wait til things cooled off just a bit before adding water in after draining some out.

But now you've got me curious about lwco. If you open the drain, why would lwco shut burner off right away? Wouldnt the float or whatever is inside it not fall until the water level falls quite a bit? Also how would one open and clean out the lwco? Wouldnt any accumulated gunk collect at the bottom by that valve and flush out on its own when draining some water? I assume the only way to get in that chamber to clean is that you remove the lwco device and there is a plate&gasket behind it? I don't want to mess around with that...sounds like asking for trouble.

Also you should not have to reset your burner that is not normal operation and an indication something is wrong.

Yeah, so I figure. When a guy comes in the fall for annual service, I usually mention it to them. They either end up telling me that they adjusted or cleaned the electrodes and everything is good now. Or they say they tested it and everything is up to spec. Thing is though, it never fails to ignite when the weather is warmer... It happens in dead of winter when temps outside are below freezing and the basement gets colder.

Finally if anyone has a recommendation they'd like to share via private message for a really good service company in central NJ, I'd appreciate it.

mattmia2

The water doesn't flow from the boiler in to the lwco chamber as fast as it flows out of the blowdown valve so the level in the chamber falls and the float drops if it isn't stuck.

Rebuilding or replacing the lwco is somewhat involved. It is bolted together with a gasket and can be disassembled for cleaning. The manufacturer requires it be replaced or rebuilt every x number of years. There are also electronic versions that use a probe.

The lwco is a critical safety device. It prevents the boiler from dry firing if the water is lost in the boiler for some reason, a leak, a runaway control, a few other things. Dry firing not only is likely to destroy the boiler but it could easily start a fire.

Are the people adjusting the burner giving you a combustion report?

Not sure if @JohnNY , @EzzyT , @clammy or several others in nyc service your area. I know John does at least some of NJ. Look in the "find a contractor" link at the top.

Jamie Hall

They all three do. But @EzzyT and @clammy are right in that area and are among the best of the best we've got here…

Long Beach Ed

Follow retiredguy's advice.

That pigtail's older than I am.

Forcing this pigtail off without soaking it with oil can easily break it off at the base. Soak with Kroil, tap on it with a hammer, soak some more — every day for a week or as long as it takes to loosen it up. Otherwise you'll be trying to extract a 1/4" steel stump from an ancient boiler.

Better yet, forget about removing it and work on unclogging it… Use a piece of stiff stuff wire, oil, a tie-wrap, anything you can poke and work at clearing the crud out. When you make progress try blowing it clear.

Larry Weingarten

Hi, I like using things wrong. Following on the suggestion of cleaning it out, I'm wondering if a short piece of 1/4" drain cleaning spring, just cut with no bit on the end, chucked into a drill might make quick work of any clog? 🤔

Yours, Larry

mattmia2

Heat could loosen it, Another method would be to cut it after the curl and stick a rod almost the same size as the id in it so it doesn't collapse and use a small pipe wrench. Someone with some experience would be able to feel where they should try force and where they should try something else.

The elephant in the room here is that that lwco should be disassembled and cleaned anyhow.

ethicalpaul

The bigger elephant is the lwco is supposed to be replaced after 10 years

EBEBRATT-Ed

There both safety controls and they need to be maintained or replaced. I am sure the LWCO could be taken apart and cleaned. Is it worth it?

With today's price for a replacement maybe.

But look at it this way. Those controls protect the boiler and your house. If they haven't been maintained you could end up in a lot more trouble

I would replace them they owe you nothing.

109A_5

A short piece of the coiled outer sheath from a bicycle or lawnmower cable bent out at the working end to have a slight auger hook may act as a small custom snake. You could use a drill motor to turn it.

If the old pigtail is too much problem a new one with a few new pipe fittings could probably be added here (Red arrow in picture) assuming that tapping goes into the boiler, looks like that plug may come out easier.

If you choose to service the LWCO float assembly, Gasket paper can be found at most auto parts stores. On my McDonnell & Miller #67 LWCO I made the gasket from Red silicone sheet material so it is reusable and no more scraping old paper gaskets. Once set up to do so maintenance / inspection is easy.

dabrakeman

https://forum.heatinghelp.com/discussion/comment/1856985#Comment_1856985

Agree that if the pigtail doesn't come off easily after soaking with the anti-seize then this may be advisable to try vs risking breaking off the pigtail. For only $10 this tool might also be worth a try if you can't find any pure 1/4" steel spring cable that you can sacrifice. https://www.lowes.com/pd/RotoPlumber-Cleaning-Kit-Attachment/5005510875

I most certainly would run a cycle and do a blowdown to verify whether your lwco is actually functioning to turn off the boiler.

JohnNY

https://forum.heatinghelp.com/discussion/comment/1856980#Comment_1856980

I’m not sure why you would say that, @Jamie Hall

I’m fully licensed and insured and operate out of a 6000 sq ft plumbing and mechanical shop located at 591 Valley St in Orange, NJ 07050 and I’m fairly certain that I’m no less capable than Clammy or Ezzy.

Jamie Hall

Sorry, @JohnNY — somehow I associate you more with Manhattan.