Weil McLain Gas Steam Boiler

Pics?

Another common leak is the wet returns. Especially if they are under ground. Wet returns are any return pipe that happens to be below the boiler water line. Old iron pipes are noted for rotting away. And if they are underground, you will never see that leak.

" I have a brand new Weil McLain gas boiler with a Steam heating system. "

New Boiler !!! Was it ever Skimmed ?

Has this been going on since the the install ?

I'd say the boiler needs Skimming to get the manufacturing oil out of the system.

The oil coating the top of the boiler's water causes eruptions sending the water out of the boiler tripping the LWCO, possibly eventually flooding the boiler due to water being added when the system as a whole (behaving normally) really does not need more water.

20 gallons removed Vs. 4 recorded makes no sense. Maybe you have multiple issues.

If it was never skimmed it probably needs it. And it may need multiple attempts since the oil was possibly blasted into the system by the eruptions and returns slowly.

it’s carrying over and needs skimming as @109A_5 said

Weil McLain but what model and size? Does Weil McLain have a different policy on which side a single takeoff can be? AFAIK all the others say it must be on the side with the controls so that you don't get nuisance triggers of the LWCO due to the probe seeing a false low waterline due to waterline tilt.

That second pressuretrol on the right is probably a manual reset high level cutout in the event that the primary pressuretrol set lower (1.5 to 2 psi) fails. I wouldn't set it at 15 psi though because that is where the 3rd backup which is the pressure relief valve is supposed to trip, making a mess possibly. Better to set it at maybe 5 to 10 psi.

Are there 2 LWCOs on this system? which one operates the water feed? Why is the one on the right located on a pipe outside the boiler? I can see all kinds of problems that can happen with this setup

Does the LWCO just below the draft hood ever cause the burner to shut down due to a low water condition in that pipe?

Flushing means opening a valve or plug at the bottom of the boiler to force out any sediment that has built up on the bottom. A standard boiler drain valve cannot truly flush a boiler. It only allows water to dribble out through a small 3/8" opening inside the valve. To properly flush a boiler, you need a full-port 1-1/4" valve or larger so debris can be carried out effectively.

Skimming is done at the top of the boiler after it has been operated for several hours. You open a 1-1/4" (or larger) skim tapping and install a short nipple or pipe, typically 6 to 12 inches long. The purpose is to remove oils introduced during installation from cutting and threading pipe nipples and fittings.

When the boiler heats up, those oils end up on the surface because oil floats on water. This creates a thin film on top of the boiler water. That film interferes with proper boiling because oil has a higher boiling temperature than water. As steam bubbles form, they must push through the oil layer, which causes the surging you observe in the sight glass.

To remove that oil film, you need to create a gentle “waterfall” effect so that surface water flows slowly out through the wide opening of the 1-1/4" (or larger) skim port. The key is slow flow — just enough for the surface water to spill over and carry the oil with it. This process can take several hours the first time and may need to be repeated.

You cannot properly skim a boiler from a bottom drain. If you drain from the bottom, the oil on the surface will cling to the internal cast iron sections, similar to a bathtub ring. The goal of skimming is to prevent that residue from coating the inside of the boiler by allowing only the surface water to flow out gently through the skim port.

I hope this explanation helps.

you can see the skim hole in the boiler jacket to the right of the upper site glass valve, it still has jacket insulation there, which strongly suggests the nipple(valve) and cap were never installed, and no skim has occurred, your installer owes you,

or if you're handy, and with proper tools, , , , you'll need to skim more than once, do you have your manual?

there's a book sold on here, 'We've got Steam Heat", it's an easy read, and worth every dime,

https://www.heatinghelp.com/store/detail/we-got-steam-heat-a-homeowners-guide-to-peaceful-coexistence

MB23…shoot me a PM. I have helpful information for you. Mad Dog

When this picture was taken the VXT was being commanded to feed water, was this expected at this time ?

So the LWCO on the pipe outside the boiler is a secondary Safety while the one actually in the boiler LWCO Tapping on the other side is the “operating” control. That makes sense.

So your boiler's burner goes off as a result of low water then the burner comes back on before the feeder adds water, and you want to know if this is normal. That depends on how your system is piped and operating. It appears that the LWCO is working. It appears that the delay on the water feed is set properly so your boiler does not get flooded. The only other question is, does the heat work? If the rooms are at or close to the thermostat set point, and you don't have banging, and/or you don't have hot and cold unbalanced room temperatures, then I might be inclined to say that for your system that is normal.   

Is there any other problem that you want to share?  

I might try to add some more water to the system.  About 2 more inches up in the sight glass.  The idea is that the burner should operate for two more minutes before the water level goes down below the LWCO and shut off the burner. Hopefully the returning condensate will start to return before the water level gets low enough to trigger the burner to shut off.  If that stills cycles by the LWCO then you are stuck with a short cycling system.

If your boiler's burn period is being interrupted by the water quickly and significantly leaving the boiler and tripping the LWCO, I'd say it needs skimming, especially since it appears the pipe typically installed to do the skimming was never installed.

The installer should have done the initial skimming, so I would think they owe you that. The change to the return may have added additional oil to the system (depending on the pipe type used) so skimming may have needed to be done after that also.

Since your boiler has probably been puking oil up into the rest of the system for some time now it would not surprise me if your boiler will need skimming multiple times as the oil slowly returns to the boiler over time.

I'd get the skim pipe installed, a full port ball valve would be nice too. And learn how to do the skimming so you are not paying for return trips of a contractor.