Water glass puzzle

[Fred_V]

Here is a good one for playing "20 questions". This happened on the Romulus I just got running on steam Sat. The water glass acted up all day and was very frustrating. i couldn't trust the readings I was getting.

Her is a photo of the water glass AFTER I blew down the boiler at the end of the day!!! I had dropped the fire twice trying to get the glass to work. I could blow through it, no problem.

I got it fixed so send in your ideas and lets see who gets it right.

[Soot n' Cinders]

In that picture it looks like the lower valve isn't open all the way

[John_S]

Bit of trash inside the glass that would rest on the lower orifice preventing the little bit of water to drain out, but otherwise float around during operation?

[Jtrain]

Appears to to be water in the glass and the drain cock is open on the bottom.

[little giant]

Looks like the tube from the shut off valve to the top of the water glass goes up and down. Line should travel downwards from the valve to the top of the glass. I did the same thing and in matter of one second had a full glass of water and then no water. Did I win the chicken dinner?

[Trainman4602]

That doesnt matter is just equlizing the pressure. If you dont open the valves fully would then give a flase reading

[Bill Shields]

Dave is correct....lines can be convoluted...makes no difference.

I am guessing that there is something amiss with the valve (probably lower) where it goes into the boiler...blocked by something

or one of the gaskets got squeezed and closed up the hole in the center....or some sort of crap in the line...

either way, it is a line blockage.

this is one reason why I always put a valve on the TOP and the BOTTOM of the glass, so that you can check the flow from both ends to ensure that it is clear to the boiler...that and MAYBE shut it off if it gets broken

[Fred_V]

Remember I said I could blow air through all parts in the system.
Good guesses by all. And, yes it is a blockage duh.

What happened is that the bottom valve stem didn't back out far enough to get past the hole up to the glass. There was clearance around the stem so air would pass but water surface tension and close clearance would hold the water in the glass!!!

The photo shows my test of it in the shop. I injected water into the top plug and then opened the bottom valve and the water just sat there. I machined a couple of threads off the stem so it backs out farther and it's fixed. The drawing shows what it was doing.