New steam heat owner -- question about LWCO maint

SteamRoller

Hello all!  This site is astoundingly useful, in both articles and page after page of threads that I'm reading.



My wife and I moved into a house (our first) outside of Boston on Dec. 30.  We have gas-fired one-pipe steam, and the system is in pretty good condition.  Nothing egregious to report, and I'm looking at fine-tuning rather than fixing disasters.



I'm not awful with the DIY; my late grandfather was a lumberman and a welder, and knew his way around iron forging, carpentry and cabinetry, and taught me how to use all kinds of tools in his basement shop.



The house had been empty since March, but minimally heated to keep the pipes from freezing when we moved in.  I didn't know until I found this site and started reading that I needed to flush out the float-type LWCO.  I did so, and flushed out a little over a  gallon of water that was thick black grotty nasty evilness at the start, and mostly clear at the end.  The automatic water filler then did its thing and made up the water that I removed.



Now that I've started what will be a weekly ritual for the rest of heating season, I'm wondering if I should be testing the LWCO for its safety function after all the black goop I got out of it.  If I have it right, I believe I would turn off the auto-filler, and drain water out until the LWCO until it turns off the flame.



Now, being new to this, I'm a bit afraid of what happens if I drain down until the LWCO should cut in but doesn't... would I reach dry firing quickly?  Would a few seconds of dry-firing cause damage?  How does one know how low to go with draining before there's no water left?  The boiler is a Utica PEG-187 installed in 1983, so I'm approaching it with a bit of trepidation.



And yes, I'm ordering the Steamy Deal of books... and can't wait to read them!  :-)

Steamhead

The LWCO

should stop the burner before the water in the sight glass gets down to about 1/4" above the lower sight glass nut. If it doesn't, call for service immediately! Use the Find a Contractor page of this site to locate someone near you.

Jamie Hall

To add to Steamhead's comment...

chances are that if the auto feeder kicks in, the float is free (thanks to your flushing!).  Checking is easy: turn off the water supply, open the LWCO blow down with the boiler running, and when the water level drops to near the bottom of the sight glass the burner should stop.  If it does, wonderful; check is complete.  Close the blowdown, open the auto feeder water supply, check that it fills properly, and go have a cup of coffee.  If it doesn't stop, and the water level in the glass is at the bottom of the glass -- just about to disappear -- close the blowdown, turn the boiler off by hand (I assume there is a switch handy?) and the check is complete -- only it failed.  Turn the automatic feeder supply back on, check that it fills properly, and go call a pro. to have him or her come to find out why the LWCO didn't work.  Then have your cup of coffee.



If you haven't let the water level get below the bottom of the sight glass, you won't have hurt the boiler at all.  It won't dry fire in the length of time it takes you to close that blowdown valve and turn off the switch by hand, if need be, no fear.  DON'T keep the valve open after the water drops below the sight glass, though!!! That could cause damage.



Myself, if I had a boiler where I knew the LWCO didn't cut off the burner on low water, I would only run it if I absolutely had to AND if I were standing there watching the water level while it was running, prepared to shut it off if the water level got too low.  Others would go farther and say not to run the boiler at all.

SteamRoller

A few more LWCO questions..

Thanks for the replies!   I need to clean the inside of the sight glass first, as it's crudded up enough to make seeing the water level difficult, and almost impossible in the bottom inch, but I'll test the cutoff function when that's done.



Just to see if I would get any more black goop, I flushed out a little more last night.  It looks like I'm getting somewhat clear water at the tap, and rust-colored in the bottom of the bucket.  Is this about right, or should the water be even more clear?



Not that I'm really tempted to fiddle with it, but is the float-governed auto fill set "by eye" or is there a measurement to set fill start/stop?

Jamie Hall

Gloop

sounds like your getting about what I would expect to get when you blowdown the LWCO.  I'd not do it, once you get everything straightened out, more than once a week.  You'll never get really clear water out of it...



The setting of the LWCO and auto fill is governed by how it is mounted on the boiler; so far as I know, there is no adjustment.  I could be wrong...

SteamRoller

Thanks!

Thank you! 



(I've got float valves on the brain, now... returning my 28 year old motorcycle to service after a few years' rest will involve disassembling the four carburetors, cleaning gunk out of all parts including  float valves, and adjusting the floats so they feed fuel at the right time...)

BobC

Clean / replace gauge glass

Here are some notes from earlier posts on how to get the gauge glass out - hopefully without breaking it.



Bob





clean / replace gauge glass

@ December 28, 2010 12:35 PM in How to Clean Out Glass Gauge

To clean out the gauge glass you have to remove it and before doing that you want to have a pair of Gauge Glass Washers on hand and probably a new Gauge glass as well. the process of removing the glass will destroy the gauge glass washers and you may damage the glass while taking it out.



Once you have the washers and a spare gauge glass you can take the old one out but first shut the boiler down and let it cool a bit..



First close the valve above and below the glass to isolate it. Next loosen the hex bonnet nuts that hold the glass in place and slide them towards the middle of the glass. Now you should be able to lift the glass out, it is longer than the open space you have so you have to slide it down into the lower valve so you can tilt the top clear of the top valve. You will see remnants of the old washers on the glass and stuck inside the bonnet nuts. It usually takes a knife or screwdriver to scare the residue out of the bonnet nuts. Clean the glass with some soap and a bottle brush, or just use a new one and clean up the old one as a spare.



To put things back you have to slide a washer onto one end of the glass and then slide both bonnet nuts on; the slide the washer onto the other end of the glass. now you have to put the bottom of this assembly into the lower valve and then tilt the top of the glass to get it into the top valve. Now hold the glass so it is centered in between the two valves and tighten one of the nuts so it engages a couple of valve threads. then tighten the other nut to engage the other valve. Tighten both nuts hand tight and then use a wrench to tighten them another turn or so.



Now open the valves above and below the glass and fire up the boiler. As it comes up to steam you may see some weeping from one of the valve/glass ends, just tighten up that nut enough to shop the weeping. Over the next few days you may have to tighten the bonnet nuts a bit more.



*********************



Where to buy

@ December 28, 2010 3:34 PM in How to Clean Out Glass Gauge

You can get both at a local supply house, in the old days the local hardware store carried them but those days are gone. You have to know the diameter and the length you need.



Because the glass fits into both valves the measured length between the nuts is not right, you have to round it up; the measured distance between my tightened bonnet nuts is just under 5" so I needed a 6" gauge glass.



The rubber washers are about 5/16" high, as you tighten the bonnet nuts they compress and seal against the glass.



The gauge glass washers can be had at McMaster Carr - http://www.mcmaster.com/#gauge-glass-washers/=acibyj  They sell gauge glass as well - http://www.mcmaster.com/#gauge-glass/=acicxg from 8" long on up. If you need a 6" length you have to buy a longer length and then cut it to size.



8" and 12" seem to be common lengths, my Burnham boiler uses a 6" X 5/8" gauge glass and i bought a cut piece from a guy on Ebay (because i didn't want to buy a gauge glass cutter that I would use every 5-10 years).