Weil Mclain Boiler Problem

adwheat

I had a new Weil Mclain gas boiler Model EG45SPIDN installed recently. The system is one pipe steam. I am observing the following:
When I raise the thermostat 2 degrees the boiler will shut down, add water (low water cut off) then continue the cycle until the temperature rises 2 degrees. However the water level in the sight glass rises from the 50% level to about 85-90% percent. If I raise the house temperature 2 degrees when the water level in the boiler is at the 85-90 % level no additional water is called for.
The installers say that the boiler will operate OK with the water level at this 85-90 percent level.
It seems to me that I should be able to adjust the thermostat by more that 2 degrees. Also it seems that the operating
water level in the sight glass should be about 50% and not 85-90% It seems that the installation should have included a reservoir of some sort?
Please advise

KC_Jones

Post some pictures of the install. It sounds like you are surging for sure. That is either caused by oils in the water or bad piping or a combination of both. Did the installers skim the boiler? That is a must to prevent what you are seeing. The water level should be able to run at the 50% mark without adding water. If your installer doesn't understand that....that is worrying of what else they don't know. Post some pictures of the boiler and all the piping around the boiler so we can determine what is going on. BTW I could easily raise my house 10 degrees and not see what you are seeing so your expectations aren't unreasonable. I doubt very seriously if you need a reservoir for a system that size.

nicholas bonham-carter

Try valving off the water feeder, and observing the waterline as the boiler fires. Does it drop?
If the system adds water at every heating cycle, it will become waterlogged, and noisy.
Was the boiler ever skimmed? Oils left over from the installation will float on the top of the water, and cause an unstable waterline, as the steam is interrupted, throwing lots of water up into the pipes, (think of "oil on troubled waters")--NBC

Jamie Hall

Two different things here, at least. First, the boiler will operate quite happily at 80 to 90% on the sight gauge. Not a problem. You don't want it over that, but that's OK. You may well find that if you try to operate it at a lower level the autofeeder will kick in. Skimming may help -- less bounce -- but the lower level may be marginal. That depends on the setting of the autofeeder -- if you want to operate lower, and you want the autofeeder, you are going to have to fix that. That's your choice. Note that the autofeeder level and the low water cut off level are not necessarily the same!

The cycling on a two degree rise strikes me as a pressure cycling. Can you check that? If it is, it is much more likely that your boiler is oversized for your system or that you have inadequate main venting -- more likely the former, unless the cycling starts very early. If you try a greater rise, what happens? I would imagine that all that would happen is that the boiler would continue to cycle on and off until the thermostat was satisfied. Try it and report back, if you would.

Paul48

Any one taking wagers there is no equalizer? We need pictures

ChrisJ

Pictures please.

adwheat

Hi,
Thanks to all for your comments. Attached are a few photos that may be helpful. I am going to try a 4 degree increase to see how
the water level behaves.

ChrisJ

Can you give us a picture further away showing the piping above the boiler that we can't see?

So far I don't see anything horrible and the first one to insult the copper equalizer get's a dirty look.

SteamedInWharton

ChrisJ said:

So far I don't see anything horrible and the first one to insult the copper equalizer get's a dirty look.

I was expecting to see much worse. On the plus side, he has a skim port, it's not a colliding header, the mains are in the correct order, and it looks like a 24" vertical rise to the header. Obviously we can't see under the insulation to see if there's any more copper, but this installation doesn't scare me like many others I've seen including my own.

Is that boiler model OK with a single riser? Never mind I went and read the manual.

KC_Jones

I agree with Chris. I am going to suggest it needs more skimming, looks like they actually installed the skim port so shouldn't be a big deal. To the OP do you know how much skimming they did already? Skimming take a lot of time.

Paul48

Looks like a full sight glass, and the top inch is brown.

wcs5050

Oh the allure of doing copper on the return.
Nice insulation job!