LWCO Busted - Options???

AdmiralYoda

Its that time of year and I drained and flushed my steam boiler before turning the heat on. I tested the LWCO and guess what....it doesn't CO.

I admit, although I'm slightly more educated about steam now than I was when I bought the home...I never maintained it properly. The McDonnel Miller No 67 is apparently supposed to be taken apart yearly and replaced every 10 years. All I've done is flushed it regularly-ish..... and probably not correctly.

I've been here for 10 years and the boiler is 37 years old. I'm guessing that its the original and that its never been taken apart and cleaned.

I properly tested it for the first time ever last night. It doesn't cut off. Great. It may have been this way for 3 months or 30 years, who knows.....but I need to do something now.

I did a blow off under pressure and got a little gunk out but it still doesn't cut out. I will try this every day for a week so see if it helps but is there any other tricks? Can I open up that little port near the sight glass and stick something up there?

This is a very important safety device and I intend to do the right thing...I'm just hoping to try the cheapest first before I call in a pro. Any last ditch efforts before I call in the cavalry?

I have a family and will make it right...just trying to see if there is an easy way out. I was planning on calling Charles Garrity (charlie from wmass) this spring to have the boiler replaced. So I'd prefer not to spend more than I have to.

Thanks!

Fred

Your best bet is to order a set of gaskets, take the MM67 apart and scrape it out. In all probablility, the float is hung up on the gunk on the sidewalls or the gunk in the bottom of the unit won't let the float drop enough to shut the boiler down. After that long, you'll be surprised how much gunk has built up on the side walls and floor of that unit. That will cost you maybe ten bucks. The next best thing is to replace the entire unit but that gets a little pricey, between $250.00 and $400.00 bucks, depending where you buy it. You need to fix it. Clearly you already understand that. If you really intend to have Charles Garrity replace that boiler, spend that money on the new boiler. It will come with an electronic LWCO and probe. Garrity is a great choice, BTW. If you intend to continue to use this boiler until it fails, rebuild the LWCO. I know the manufacturer says to replace it every 10 years but once you get it apart you'll see there isn't to much that can fail, except the copper float and maybe the switch, on the end of the unit. If either of those are bad, just buy a whole new unit. Those parts cost almost as much as a new unit.I put a new unit on my 34 year old boiler a couple years ago and cleaned up the old one to use as a spare, if ever needed.

ch4man

you say you've never maintained it, you know it needs to be pulled apart and cleaned.
now it doesn't work and you know it is a very important safety device.

not sure why your asking when you know the answer.
you need either...
one gasket and some U tuber videos
or just make the call.

right now your boiler should be shut off until repaired. sorry for the tough love....

AdmiralYoda

Thank you. I'm too tired too look but I assume this stuff is available on MM's website?

My worst fear is breaking something while taking the LWCO off and it costing tons of $$$. Especially since it will be headed for the junkyard in 6 or so months.

Thats why I was hoping there was a tried and true'd...."oh yeah unscrew this bolt and jam a screwdriver up there" approach.

newagedawn

the only tried and true is to rebuild it

ch4man

actually we are all correct. its about a half dozen screws to remove the donger (float) and clean the mud out. this usually destroys the gasket i spoke of. yet sometimes the float is beyond cleaning.
look for the part called the #67 head assembly and be sure to match the voltage and whether its a manual reset or not.

AdmiralYoda

The boiler was purchased 37 years ago and I bought the home 10 years ago. I was a wee lad then and didn't know a thing about steam except that a plumber friend said to flush the lwco every now and then.

Now that its time to replace this beast I came here and learned a few things.....and learned proper maintenance and that I have

AdmiralYoda

Thanks guys. So it sounds like I don't have to physically take the lwco off of the boiler to clean the bits. This is good news.

I intend to get the gaskets and try and clean it up. Worst case is I break it or am unsuccessfully and I'll have a pro install a new one.

I burn 50/50 with a wood stove so I'm not in crisis mode.....yet.

Can anyone point me to a good writeup or video of what exactly to take apart and proper cleaning tecniques?

Alan Welch

just removed and cleaned one last week, I think it was 15 screws in total,the final 8 that hold the float can be almost impossible after that many years .Another way is to shut off the power, drain the unit until no more water comes from the blowdown valve. then remove the 4 screws that hold it on to the low water cutoff, and scrape out the crud thru the bottom opening. They make replacement kits ( think its number 14 blowdown kit) with new threaded plate, ball valve, gasket , nipple and bolts. before you put it back together you should make sure the float actually drops and shuts off power, you can add a little water to boiler and flush out bigger chunks if needed.

EBEBRATT-Ed

Too much risk and no reward. It's a 37 yes, thirty seven year old SAFETY CONTROL.

It's outlived it's useful life. replace it.........or run the risk of replacing the boiler before your ready to.

And make sure the connecting pipe and boiler tappings are clear

JUGHNE

You might make it another season, I see you plan to get a new boiler next spring. IIWM I would keep flushing this until it ran clear.

Remember when you blow down it MUST shut off the burner and activate the water fill. They are only truly tested when the boiler is firing and you kill the fire. Not just running water out.

I would flush/test it weekly with a good long flush. This is adding more fresh water than recommended but you are getting a new boiler....right.

If no new boiler coming I would put a new one on........if your car tires were 37 years old but still held air would you continue driving it?
BTW, I will say that I drive a 1932 firetruck with what might be the original tires, it gets about 10 miles added each year at 5 to 15 MPH. Tires see the sun twice a year. But this is not a steam boiler.

AdmiralYoda

I've always flushed it weekly or so during heating season. I always did it cold and not when its producing steam.....which I do now.

It has always flushed with plenty of volume and never a trickle. Generally, after a quick shot of rusty water it always runs clean.

I bought the gaskets and plan to it apart this weekend. I'm going to try and do it while its still on the boiler to not disturb and of the old piping. If I'm unsuccessful I'm getting a new LWCO, period. I'm on the fence about doing that myself. I am plenty capable...I'm just hesitant to start messing with 37 year old fittings and getting myself in a tight spot.

Oh....and I don't have an automatic water filler. I am the water filler when I check on it a couple times per week. So even more reason to get this working NOW.

And no mater what happens.....the boiler is getting replaced at the end of the season.

Fred

That old boiler may have more life left in it than anything new you might buy. They don't make'em like they use to.

AdmiralYoda

You may be right.....but I've got a suspicion that there is a crack above the water line. It goes through water faster than it should. In the heart of winter I'm adding a fair amount of water once per week.

Plus the piping coming out of the boiler is all wrong.....and I have no main vents. It's time to invest I'm thinking.

Fred

Yep, Sounds like it is time.

AdmiralYoda

UPDATE!!!! So I ordered the replacement gaskets and attempted to clean the lwco out this weekend. SUCCESS!

I was able to do it while it was still attached to the boiler. It wasn't quite as gunked as I was expecting but was still plenty dirty. $12 and it's back up and running.

So lesson learned...flushing it weekly just isn't enough....you have to do it while the boiler is running to make sure the lwco cuts out. Seems obvious now but oh well.

$$$$ saved

Fred

Great! You do need to blow it down while the boiler is running to make sure it shuts the burner down. You really need to clean it out once every year or two. The blow downs help but the LWCO walls and floor will still accumulate a build up.