Weil McLain Boiler - Recommendations for Tune Up & Steam Release

I have an old WM Boiler that I inherited when I bought my house 10 years ago. No problems until yesterday. The steam release valve that sits on top of it was spewing hot water. I used the water discharge valve to empty a couple of buckets of water. Turned it off and started it today. Removed a few more buckets and now the water seems stable at the right level (eyeballing the glass tube water level). But there is still excessive stem coming out of the release valve. It would seem that a check-up is in order, maybe some replacement parts. Weil-McLain’s website has a search engine for local WM contractors. I’m in Greenpoint, and I got a lot of hits: Billharz; Gateway; E. Mule; All Systems Mechanical; John Sideris; Vigilante; Aladdin. Happy to hear any thoughts in general as well as recommendations.

eagleman22

in Plumbing 8 years and 5 months ago

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Master Plvmber | 8 years and 4 months ago

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By repositioning the relief valve, your plumber created a code violation. The new relief valve is piped on its side without a “blowdown” pipe. He used too many fittings. By Code, the valve has to be positioned straight up and have a pipe connecting to it and then terminating safely within 12″ of the floor. That pipe is there to protect you in the event the valve activates so you don’t get scalded. A plumber licensed in NYC should know better.

eagleman22 | 8 years and 4 months ago

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Hi – so, here’s the story. I contacted Billharz Plumbing (after finding them via the WMcL website) and they came to install new brass pigtails, a new pressure relief valve, re-positioned to face out and down) and they also put in an internal cleaner powder, with the instructions of not to empty out any hot water until 3 weeks time. The boiler is running extremely quietly and much faster to get to heat. No issues at all. I will have BP back to do a full cleaning of the flue, boiler heating elements, etc. The man who installed all the new parts also commented on the age of the boiler (older than him – 50+ yrs old), but said that he’s seen WMcL boilers that last a long time. Thanks everyone for all your helpful comments – one of the reasons I love Brownstoner.com! [BoilerNewParts022017](//muut.com/u/brownstoner/s3/:brownstoner:j9hN:boilernewparts022017.jpg.jpg)

vtyromjknnshzly | 8 years and 4 months ago

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no-permitz your comments have been removed because they violate our commenting policy. Personal attacks are not allowed. If you continue, you will be banned again.

BobMarvin | 8 years and 4 months ago

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Actually, that was me. I’ve mainly removed obvious spam, such as links to service “providers” in California, or Canada, or the UAE, but personal attacks are even more inappropriate.

Master Plvmber | 8 years and 4 months ago

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Everything in that picture: the boiler, the pigtail, the relief valve, the pressuretrol, the aquast, is the oldest thing on earth.
Please don’t put any real money into that boiler. Be safe and buy new stuff.

steam_man | 8 years and 4 months ago

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Well? What happened?

steam_man | 8 years and 5 months ago

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If the pigtails are clogged then the pressuretrol wont operate as I described. The boiler will keep making steam till the relief blows. Scary. Make sure they put in brass pigtails.

eagleman22 | 8 years and 5 months ago

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eman134; steam_man: Plumbers coming tomorrow to fix. They mentioned replacing the pressure relief valve and also mentioned the curled pipe item to the right of it (see pic). Looks like a ‘pigtail’, but there’s another to lower left too. The water level has stabilized to the marked line on the glass tube. When the heat is on, only steam is coming out of the pressure relief valve – which you can see with the orange rust color on the top of the boiler. [20170212 Boiler](//muut.com/u/brownstoner/s3/:brownstoner:BVTV:20170212boiler.jpg.jpg)

steam_man | 8 years and 5 months ago

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My thoughts exactly.

eman134 | 8 years and 5 months ago

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clogged pigtail or tee going to the pressuretrol. You might as well replace them all , including the pressure relief valve, and if you can , replace the pressuretrol with a vapostat which a much more exacting control

steam_man | 8 years and 5 months ago

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I’m interested to know what they find.

eagleman22 | 8 years and 5 months ago

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Thanks Steam_Man. I’m awaiting a licensed plumber with WMCC creds to come today to diagnose. Hopefully its some replacement parts.

steam_man | 8 years and 5 months ago

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Could be a couple of different causes for this. I guess you figured out that when the last resort safety item is activating then this is NOT a good situation. I’d say more than likely you have a bad relief valve. See there are a few things to think about. Your boiler should have 2 small boxes. One is the operating pressuretrol and the other is the high limit pressuretrol. If the operating limit goes bad and the burner is allowed to fire to the limit set at the high limit pressuretrol then the high limit is supposed to trip the burner off. The burner won’t fire again until the pressuretrol is manually reset. If this process isn’t occurring then I’m worried. Those pressuretrols should prevent the relief valve from ever blowing off. When the relief valve blows we usually get a little worried. Looking at the boiler and ensuring it is cycling on pressure will verify the pressuretrols. Also checking continuity across the pressuretrol during operation will verify if the pressuretrol is good. Water level during operation is also an indicator of what’s going on. Bottom line is th ose pressuretrols should be cutting off the boiler before relief blows if they are in good working order and set properly. Have a reputable heating specialist check it out.