McDonnell & Miller (MM) PSE 802-U-24 LWCO ?

Corktown

Tonight I was visiting at a buddy's very nice home in Detroit's Boston-Edison (yes, that Edison) District and I took a minute to visit his boiler room. There were a number of potential issues to my untrained eye, but what jumped out most was the site glass on his W-M LGB boiler (the exact size was not marked on the sticker, but the house is 8000 sq. ft.). There was no visible water in it, just some crud in the last 1/2 in. or so.

My friend is not maintenance-minded and told me that all he ever did was drain water out of the M&M No. 61 LWCO one the side of the boiler when the mood struck him (!), and almost certainly not while the boiler was steaming, as he didn't understand the whole blow-down concept at all.

So now, of course, I'm even more concerned about low water in the boiler, but I was a bit wary of adding water with the manual button of the M&M auto-feed, keeping in mind the possibility of the water passage to the bottom of the sight glass being clogged and not wanting to overfill the boiler. I then noticed a M&M PSE 802-U-24 LWCO on the other side of the boiler. The boiler was off, the green light on, and when I briefly (likely less than the two seconds the online manual references that I looked at when I got home), only the red light flashed for some time, perhaps the 15 seconds mentioned in the manual. The red light then turns off, and the green light is on at this point.

So, is this what is supposed to happen in the scenario I've described? I realize from my later reading that formally the test should take place with the boiler running. I don't know if this cut-off has the same two-level light indicator that the one on my boiler has, but the green light was fairly bright.

Is the boiler o.k. for the night, or should it be shut off until the water level can properly ascertained? Or should he have the boiler fire and run through the test procedure that I found online, which has one depressing the test button for more than two seconds, followed by a series of flashing green and red lights, and auto-feed and boiler off and on sequences.

P.S. What do 'DOB' and 'DOM' stand for in the instructions?

Thanks in advance,

Corktown

Corktown

Here's the boiler. There are other issues that I will ask about in a separate post ....

EBEBRATT-Ed

I would shut it off and get it serviced. The general rule is "if you can't see the water level in the gauge glass the boiler is not safe to run"

In spite of some inconvience you may have saved your friends boiler. Maybe @offdutytech will respond he may be in that area or can recommend a contractor if your friend needs one

Corktown

Thanks, @ EBEBRATT-Ed. I’m going to contact my friend and relay your advice.

offdutytech

Corktown just shoot me a text if you need a service call to check the boiler out. Sounds like a little TLC is needed for the system

Corktown

@EBEBRATT-Ed and @offdutytech, I took out the lower sight glass valve and it wasn't clogged, but there was no sign of water. My friend had to hold down the manual refill button on the water feeder for at least four minutes before water came out of the opening. Of, course, I then added water to the proper level.

It's a big boiler that holds a lot of water, and obviously the water level was too low, but it seems to me that the level was more than a little bit below the bottom of the sight glass.

What do you think?

P.S. @offdutytech I'll give you a call and we'll talk about getting you over there when you're in the area. There's still some issues to be addressed. Also, there's some cool things in both the basement and the carriage house! ....

offdutytech

At this point I would say you will have to pull the probe out. M M recommends to remove and inspect the probe every five years. Replace the probe every ten years. Replace the control box every 15 years.  Page 14 of the manual. 

Steamhead

@Corktown and @offdutytech , that looks like a Weil-McLain LGB series boiler. The probe-type LWCO looks like it might be mounted in a drain tapping- if so, it's too low. It needs to be mounted on a manifold at the lower reaches of the glass.

Hydrolevel makes suitable manifolds for this purpose.