Old steam system - no water in glass sight?

Lee28

Sorry for the long post - I like to be thorough.



We bought this house fairly recently with an old steam system. No problems with it last year and never any indication that anything is wrong with it. We've got a pellet stove too so we try to run the boiler as minimally as possible to save on costs. Anyway, we went to start it up this year after cleaning out the boiler and noticed that there was no water in the glass sight. The water level has generally been consistently at half full up to this point.



Here's the thing: we didn't notice the water level at first and ran the boiler for a couple of hours before getting the feeling to go check on it. It heated the house fine, radiators warmed up nicely with the usual hissing sounds of steam, etc. There was no indication that anything was wrong and the low water cut off unit didn't cut off - it was just one of those feelings to go check since it was the first run of the season.



So, when we saw this, we traced the line back and found the water-in pipe (forgive my lack of technical knowledge of terms. I don't know much about these systems and the proper terminology.) We opened the valve and could hear the water running into the system but still nothing registered in the sight glass. We only let it run for 60-90 seconds because of fear of overfilling. Opened the valve on the big black metal thing (is that the blowdown? - again, no idea what this stuff is called) and some mucky water came out but not much. Opened the drain on the back and a fair amount of water came out with some decent pressure - so I know that there's water in the system - but turned it back off without draining the whole thing.



We've also checked inside and out for leaks and can't see any indication that there are any. With the amount of water we added without anything registering, we'd expect there to be some significant wetness, right?



So, from the novel that I've written above, here's what I get from it (and as you can tell, I'm no heating expert, so please correct me if I'm wrong):



1. The lack of water in the sight does not appear to be from a massive leak in the system or we'd see water everywhere (either inside or out) after running it for as long as we did. Also the fact that it came out with a decent flow when we opened the drain in the back supports this, right?

2. The fact that the system ran and there was steam running through the pipes (we heard it and nothing sounded off) means that there is water in the system.

3. Number 2 above seems to indicate that the problem is not with the LWCO since there is indeed water in the system so there would be no reason for it to cut off to begin with.

4. This leads me to believe that the problem is with the sight glass itself and that it may be too clogged up or full of gunk to register the water level properly.



I'd love to have some professionals weigh in on this since I'm just a homeowner who likes to fix things but knows very little about steam heating. We haven't run the system since and are obviously concerned about blowing the house up or something like that.



Is my logic sound and, if so, what is the next course of action to rectify the problem? Or, if my logic is just plain wrong and not as logical as I think, please correct me.



I really want to understand how this thing works and not be out a fortune a week before Christmas! Thanks!



(Oh, and I can add photos shortly. Just wanted to get the process started. Thanks again!)

Jamie Hall

First off

I am not a professional -- just a building super.  That said, it sounds as though the lines leading to the sight glass (and, not incidentally, the low water cut out) are gunked up.  It happens.  This really isn't a homeowner type thing to play with, unless you are reasonably handy with tools.  For one thing, it is all too easy to break the sight glass!



Probably the best thing to do is to find someone in your area who is reasonably familiar with steam -- you might try the "find a contractor" tab, searching by state, no zip code.  Not all plumbers are familiar with steam systems.  He should clean all the ports -- those for the sight glass and the low water cutout, but also the ones for the pressure gauge(s) and the pressuretrol -- and make sure they are free.



In the future, the low water cut out drain should be operated at least a couple of times per month, until the water isn't gunky (it can still be coloured), to keep things a little cleaner.

conversiontime

fill a bit more

A clog in the site glass sound like a possibility, but you said last season it actually was half full, correct? If so that means the water went somewhere vs being clogged. The low water line in the boiler is often below the bottom of the sight glass, but not by much--so you could feasibly have steam but still be low on water. (normally LWCO prevents this but could be faulty)--that is what you first purged



So first try to fill a bit more. If there is a skim port, you could open that up and see if the fill reaches that to figure if the site glass is the problem.

Lee28

Pics attached - what's the skim port?

Thanks for the replies. Can you tell me what the skim port is please?



Also, I've attached some pics. Sorry, the lighting is terrible in the basement.

bustoff315

LWCO

That big black thing is your low water cut off switch and is VERY important that is working correctly. After months of neglect they tend to plug up very easily. Make sure that both valves on the top and bottom of the glass gauge are open.

Lee28

Gotcha

We opened the low water cut off valve and drained out the crud a couple of times. There's not a lot coming out of it by any means, more like a trickle of gunk each time. Is this what it should be like? I always had electric baseboard heating so this a totally new. We also made sure the valves to the glass are open and they are.

mcsteamy

LWCO

If the boiler is running and you pop open the low water cutoff drain valve, does the boiler shut down?    If not, you've got a problem. 



Like others said, it seems unlikely that the water isn't getting into the sight glass.  Put quite a few gallons into that boiler and see if it shows up.  The best way is to find a way to manually fill so you can track how much you put in.  If water shows up, fire the boiler and check closely for leaks, and also check for white "smoke" coming out of the chimney.  If the boiler is cracked, you could be blowing steam right up the chimney and never know it.

nicholas bonham-carter

Water or not?

If the water is very clean, and the boiler is over-full, it can look as if the sight-glass is empty.

When you find a local steam pro, ask him to show you the procedure for routine maintenance.--NBC

Lee28

How long should it take to fill?

Looking at the pictures and assuming that the water is low, roughly how long should it take to fill the sight glass to a level where the water can be seen?

conversiontime

water feeder vs lwco

Just want to make sure you are using water feeder-- should be inline with water line to boiler. Most  have manual button on the top you push down to feed in water manually. If LWCO is not functioning, and yours sounds like it is not, then you need to add via water feeder itself.



Avoid thermal shock if adding lots of water by turning boiler off for 2 hours +-.  Fill for 30-60 seconds using manual feeder and the site glass should start to fill. If it goes past a minute without even filling then stop as leaks should then be looked for in the boiler itself.

Lee28

Water feeder

Yes, we're using the water feeder which is an in-line valve from water to boiler. As far as I can tell, there's no other way to add water to the boiler - I don't see any buttons to do anything automatically. It's a pretty basic looking system from what I can tell. If I'm missing something, please let me know what I should be looking for in the photos. Thank you!

Hap_Hazzard

What do the try-cocks tell you?

On old boilers like this they often have try cocks in addition to the new-fangled glass gauge. These are two funny-looking faucets mounted at roughly the same height as the upper and lower gaugecocks. Yours are visible in that picture showing your pressuretrol in the middle of the top row of photos.



Their operation is quite simple: if you open the lower one, water should come out. If it doesn't, you need to add water. If it does, try the upper one. Water should not come out of that one. If it does, the boiler's too full; you need to let some water out. They may well be plugged too, but it's worth a try. After all, that's what they're for.

Lee28

Suckers just sheared right off

I am hating this old system right about now. I tried to open the try-cocks and the handles just sheared right off. Hope they're not essential to the operation because we can't afford a new system. It may be a cold winter...

Lee28

How long does it take to fill?

I asked this above but the post is now sandwiched between others so maybe that's why I'm not getting an answer, but how long does it take to fill a boiler like this generally? Let's assume it's empty - how long should I open the water feed valve for before expecting that it's full enough to register halfway on the glass sight?

Hap_Hazzard

Well, at least you tried--no pun intended.

As long as they aren't leaking they're not a problem. Most boilers don't have them. I think they only kept them on those old boilers because some of the old-old-timers didn't trust them new-fangled glass gauges. Over the summer you can think about removing them and plugging the holes.

Lee28

Haha yep!

Yeah, the pun came to my mind too! They don't leak - they're jammed in the closed position pretty firmly and probably have been that way for 50 years. Good to know that we can just leave them or remove and plug without too much of an issue. Thanks for the suggestion. It was definitely worth a try.

neilc

site glass fill time

so many variables to how long a fill time,

feed pressure,

how much is, or isn't, already in the boiler,

you really need to have someone reestablish the site glass level,

whether it's clogged, or the water level too high or low,

you'll never know until the site glass is working again,

this, and that low water cutoff, they're both safety safety safety related,

and purchase Dan's book, "we got steam", great homeowner / steam owner read.

Lee28

Update 1/3/13

So we're making slow progress at this but have now cleaned and de-gunked the lines coming in to the glass gauge and the LWCO. Put it back together, turned on the water and we now have water in the glass sight! Hooray! We'd fire up the steam boiler and test the operation of the LWCO blow down assembly while running, except for now we have a pretty steady drip coming from where the float assembly meets the large black part of the LWCO. Is there a trick to bolting this thing back on or is there a gasket that would rectify the issue? It was pretty cruddy and my guess is that it's just not sitting tight now because of this. It's a McDonnell 67. Any tips?

Pipedope_2

LWCO

When you say leaking from the float assembly, I'm guessing you mean from the 4 screw plate above the blow down valve? If so, you can disassemble it and cut a new gasket if you have the material. they also sell a kit with the gasket and a new valve for the LWCO. Might just be easier.

Lee28

LWCO

Exactly. I actually just disassembled the thing again and noticed a subtle notch on one side. Flipped it over and screwed it back on and that seems to have taken care of the majority of the dripping. Will look into a gasket to seal it up nice and tight. Thanks!

Lee28

Conclusion

Just wanted to post the conclusion of this ongoing saga, if for nobody's sake but my own. I reassembled the LWCO, fired up the boiler, and tested the blow down assembly and everything worked like it should. We are back in business!



Thanks everyone for the helpful suggestions and tips!