Cause of overheating of rear sections on WM 680 steamer?

The Steam Whisperer

We are working on a 2 year old steamer that we installed. Carlin gas burner and dual Hydrolevel low water cutoffs. I want to see if you have any ideas on this or if you have had any problems. This is the typical set up I've seen most of you other steam specialists use and we have had great luck with the 10 or so we have in place. Nearly all 10 use this same set up with the Carlin 201 or 301 Gas burner specifically for these boiler models. IIRC, the 680 is the largest model we have installed.

Steamhead

Looks like either the waterline tilted, or there was an undue concentration of heat back there. The near-boiler piping is NOT the issue. And I see the refractory target wall on the rear section, as it should be.

Check the burner and make sure the right diffuser plate was installed in the air tube, and that the orifice was drilled out properly and the gas pressure was right- yes, I know you did when you installed it, but it can't hurt to check again. Something might have changed.

The other possibility is that there was some sort of blockage in the section that kept the water from circulating through it.

You need to get the W-M and Carlin reps involved. Not sure who does Carlin out your way but I can find out.

EBEBRATT-Ed

If the boiler MFGs tested these properly their probably wouldn't be these issues but they don't so there will always be issues.

On residential boiler and furnaces they sell them like washing machines where 1000s of them go into the field and if there is a problem it will show up.

This comes from pushing the ratings too high.

Also as I have said in the past.

They come out with a boiler lets say it's 6-10 sections

Do you thing they test a 6 section with a Carlin, with a Beckett, with a Riello, with a Power Flame?
and then do they do a 7, 8,9 and 10 section

And then do the same thing for oil? How many combinations do you think they test?

They don't , they guess

I have been through this years ago.

On Commercial stuff they cheat, they don't put the hours in needed to test every combination.

They lie and let the guy in the field figure it out. been their, done that

The Steam Whisperer

Do you guys know where I can get 2 intermediates and one back section. So far nothing in Chicago except 1 intermediate. I may have to put in a temporary boiler ( one of the two Peerless SC that were overheating burner heads).

Steamhead

Ferguson is our go-to for these- do you have one near you?

The Steam Whisperer

Ferguson has nothing. I've almost never done any business with them because they pricing they give me is about 50% above what I can pay retail for an item elsewhere. Lots of others have had that experience with them in Chicago. I don't really know how they stay in business as they seem mainly focused on retail sales, not contractors.

Do you set up your 80 series boilers with full pressure firing or negative draft in the chamber? The guys usually set them up close to zero in the chamber. I'm just wondering if the vent connection at the rear could have been pulling the flame towards the rear sections.

EBEBRATT-Ed

I would try and get through to Weil Mclain or the local Weil mcLain rep

Steamhead

We do ours with a slight positive at the breech, as specified. But I doubt that was your problem.

Is this the only one you have that cracked?

The Steam Whisperer

Yes, I think we only have one more 680 and that has a Powerflame burner and a float Primary LWCO and its a year older.