Every heating season I see at least one boiler cracked because the LWCO was sticking and keeping the switch closed when the water went low. If the LWCO doesn't shut the burner off when I open the blow down valve ; I always run a stick of tubing up through the blow off valve and work that float up and down until the switch is responding immediately. I always show the home owner how it works and why it is so important to flush and check it. If the #67 is real crusty, I sell them a new one. I tell them it's about $1000 for a new LWCO or $10,000 for a new boiler. The electronic feeders fail as well. I'm a firm believer in two LWCO's on a steamer, since I've seen so many of them fail. This is a good video to show to a customer when I come across a flakey #67. Thanks for the videos you make, Gordon.
Between your videos and My heating help website I’m learning a lot , when I start in this trade i was blind but now I’m understanding more and more every day, I’m a hvac tech/ installer but in the winter we do a lot steam and hydronic boilers also we do high efficiency boilers, thanks for your videos sir
You are most welcome, Sir. I appreciate your words and more importantly, your desire to learn! The day you have stopped learning is the day you have died. These videos are my way of paying back to those who helped me and to those who are still helping me.
Hello and good morning, I just happened to find your show after another HVAC show. Your show is very informative and informational on steam components.
great video, I have one of those on my boiler presently and it is working fine. now I know how it works. thank you. The float switch on mine is square/cube.
Hello Gordon, Wow....thank you for all the points mentioned above!! I will have to find a good technician in our area and have him look into this. I have a feeling that it might be the delayed ignition, but again I will have that looked at as well. I'm thinking it may be the ignition because the smell of gas seems to be present only when the boiler starts up. Thank you again.....Ornelio from Stoney Creek, On.
Very good video. My water has plenty of deposits. Always attacking my low water cut off. This year I didn't clean off my float & check the switch. So my aquastat paid the price for the high temperature. I'm lucky it could have been worse. I drain it very often. It just needs to be cleaned every year. Tiny dozen screws are tedious
Thanks,did not know there was a better replacement and the name of the better replacements,have struggled trying to take two and make one and then could not remember which way to place the top unit towards the flow..But your video showed me which way to place the top part back on,thank you so much??
Great education you've given us. THANK YOU We have this unit and when I blow it out (weekly) it triggers the refill but last two weeks it doesn't stop filling until much higher in the sight glass than previously. A gentle tap and the fill stops. I figure the float is getting stuck. Is opening the little bolt (where you mentioned the little piece of cardboard) and digging around with a pipe cleaner a good first step?
I would open up the 1/4" hole at the top of the unit (you may have a pigtail & pressuretrol threaded in there). Don't forget to drop the water level first to just below the hole! Next, I'd poke the float with the sight glass protecting rod - push and release several times. You should hear the clickity-click of the switch. That should free up the float. At least for awhile. Others have suggested on this thread that you should take apart the unit by removing all those screws and pulling the float. Then, you can thoroughly clean the inside of the #67 of all of the rusticals. You will need to completely remove the old gasket & install a new one. I would consider replacing the #67 with an electronic probe-type LWCO if you can. What type of feeder do you have? I would replace it with a VXT instead.
The problem I'm having is the part that's rusted is leaking. Some how my radiators over flowed and we shut system down. Do I need a new boiler or just clean inside to release float ?
Awesome video. I was wondering if you could go more into detail about the wiring of that device you show at 5:20. I need to know more about the electrical connections.
Thank you! That switch is shown sideways at first (sorry!) To your left, you should see the word "top" and the numbers "1" & "2". Those are where you wire the burner circuit to. The bottom two terminals are where you wire in the water feed circuit. When the float is up, the top terminals are "closed", that is they can conduct electricity, and the burner is allowed to fire when the t-stat calls for heat and the other limits are "closed".
@gordonschweizer5154 Is there a way to trigger a call to water feeder to test if the bulb is stuck or not. If I jump the two terminals on the bottom will that work?
great video very informative. if the boiler wont turn on unless I touch 2 wires from the switch together does that mean i need to change the switch or the float area needs to be cleaned out? or is it best to change the whole thing?
When you operate the flush, can you hear the "click" of the switch operating? If not, the float might be stuck in the down position? If the "click" is heard that might mean the float is operating but the switch is bad. The instructions say if over 10 years old, to change the whole thing. Your call. If you go that route, I'd look into switching to a probe type LWCO
Hi Gordon my name is Steve I have watched many of your videos and thank you for making them. You are very knowledgeable about steam and I am not but we are learning. What I'm in desperate need of is my boiler has a McDonnell & Miller mechanical water feeder on it. On top of the manual water feeder is a McDonnell switch. It is a TYPE 2 switch looks like many years ago someone had made a plastic cam to control the switch? Well over many years that plastic has failed now. I'm sure there is a replaceable part for it but I cannot find it. My steam boiler is over 75 years old and still works good as long as we keep water in it. I am trying very hard to get the automatic water to work right, and most of all the low water switch to work again. Hope you can help me out thank you keep up the good videos. Steve in Wyoming
Thank you for your kind words! I could well be wrong, but it sounds like you may have a McDonnell & Miller #47-2 low water cut off and feeder (the 2 in 47-2 stands for...wait for it, yes, your #2 switch lol) I have a few videos on this contraption. To say it is not my favorite control is an understatement. Look up the #47-2 and look at pictures and parts break-downs online. That should get you started on getting it fixed. Definitely concentrate on the low water cut-off part of the show! I would consider by-passing the mechanical water feeder part and going to just manual feed to add water. If that is an issue, then I would beg you to consider to have installed a modern water feeder such as the VXT by Hydrolevel.
@@gordonschweizer5154 Thank you for steering me in the right direction. I found the part that I needed on eBay and it is on its way thank you again and keep up the good videos they do help a lot.
Great job explaining how the #67 LWCO works. I believe my float is stuck on my LWCO. The entire unit was replaced 3 years ago. Is there a gasket or something I need to worry about if I remove the float for cleaning? Also, while the float is out, should I try to insert a brush to remove some of the buildup of rust...or just leave well enough alone and don't go poking around in there. Thanks for your advice.
Sorry to hear that your three year old #67 is acting up. Yes, if you pull the float, there is a gasket that might need to be replaced. Any plumbing supply house should be able to get it for you. Please note that there are also about a dozen screws of various lengths and types that will need to be kept track of if you remove that float assembly. Truly a masterpiece of design (sarcasm). Once the float assembly is removed, you can chip away at any rust. Its basically a hollow shell at that point. If your #67 is rusting up that badly after only three years, you might be taking on too much fresh water due to leaks or your water is very acidic. Before you go through all that, make sure its not the switch that is acting up. An ohm meter will help with determining that. The switch is much easier to replace if needed (but they are not cheap). If you can, I'd see if you can replace your #67 with a probe-type LWCO. Fewer maintenance issues, no weekly blowdowns, and and a more reliable safety control.
Great video. I put in a new McDonald Miller switch (#11). The auto feed stops when the float is parallel to the floor - the water level in the glass tube is about an inch. The glass tube is about 4 inches. I would have thought that maybe more water will fill from the auto feed, but stopping when the float is parallel seems right. is it? Jeff
If they filled when the water line dropped only a couple of inches, the boiler would be overfilled when the condensate returned after steaming. Some systems return condensate slowly.
is there a gasket set available for this unit ? I would very much like to open it up and descale it so that I can continue to use it. iT HAS BEEN VERY DURABLE
Hello Gordon, I want to thank you for all your help in the past. Very much appreciated! I have another question. Why would you smell gas when the boiler starts up. Is this normal or? My furnace installer said that it is a normal occurance. I would appreciate your input. Thanking you in advance. Ornelio from Ontario
You are most welcome. As to your concerns, it is difficult to give much useful advice as I cannot be present to observe your system. But did the tech to a combustion efficiency analysis on your system, checking especially for CO? Did they "clock the meter" to see if your unit is overfired? Check draft/chimney? Observed delayed ignition? Leak on pilot tube? If not, I'd find another tech who will do these proceedures. If they did these things, and there is still a gas smell, is the boiler sooting up? Is make-up air to the boiler ok? are questions that might be addressed.
Both the #67 and any probe-type LWCOs have provisions for sending a feed signal to an automatic water feeder when the water level gets low. The water feed request is a convenience only and not a safety device. The only true safety purpose of ALL types LWCOs is to shut the boiler's burner off when the water level in the boiler gets too low. The probe types work pretty well with reasonable maintenance. The float types require lots more maintenance and have a much higher rate of lost boilers due to burn-outs.
@@gordonschweizer5154 good to know. My boiler has both #67 and probe type LWCO and my automatic water feeder started working again. I wonder if it was because the float was stuck. In another thread, I was asking if there is a way to trigger a call for water by jumping the terminal? This way I can test that water feeder is still working but the float is stuck.
Possibly. It depends on being able to remove several small screws that are prone to breakage. Then, you'll need the proper gasket and float/bellows part. And maybe a new switch, too. Or, Chuck the whole #67 debacle and install, or have installed for you, an electronic probe type low water cut off. Its possibly more trouble and costly, but much much more reliable.
Gordon, I recently had an issue whereby the float was stuck. I opened the valve and drained the system and the boiler kept running. I drain it weekly in the winter months. What is the best way to clean that chamber? Is pushed a brush up there with the ball valve ope and it worked but not sure I cleaned well enough.
I am so glad you discovered the infamous #67 stuck-float-burner keeps-firing *before* disaster struck. Seems like you cleared the fault. Keep an eye on that water level & keep flushing & testing it weekly. If your boiler is not that old, consider having a probe-type lwco installed.
Thank you for this info. Could you comment please on this question of mine? I have the PROBE type Low water cut off, currently on my new steam boiler. This PROBE type LWCO, does not have any way of "blowing down" this boiler, like the old #67 did. Should I have a #67 LWCO installed, on my new boiler? I am worried, that because; there is no "blow down" feature available on the PROBE TYPE LWCO, that I now, will NOT be able to rid sediment and dirt from my new boiler. YOUR input on my concern will be appreciated greatly.
You should not need a #67. No one needs a #67 anymore. The probe type LWCO is superior, but only provided the installer of your new boiler read, understood and followed the instructions that come with your boiler for cleaning your boiler properly, forever eliminating the need for weekly blow-downs. Cleaning the boiler properly within the first weeks of operation is the important thing.
Hi Gordon, your videos are very useful for the handyman landlord. I'm thinking about changing the float in my 67. Should I use a sealant with the gasket?
Short answer - less than a gallon per each opening of the drain valve. If you can, the boiler should be firing while you drain so you can observe it shutting down and then restarting when you stop draining. That is Very Important! What should happen when you first open the drain is a sudden rush of rusty water and then the flow should slow down. Shut the valve at that point and wait a few beats to allow the chamber to refill. Drain again. Maybe drain a third time. The water flowing out should get to a "weak tea" look after a few drainings. That may be a bucket full or not. Best to Not just open the drain and fill the bucket in one go, but cycle the valve for the most effective flushing.
@@gordonschweizer5154 this is extremely helpful. We just moved in in July and this is my first winter with one of these things. (We live in Massachusetts. Have oil heat.) I don’t know how much maintenance the previous owners did on it. I drained about a gallon out and it’s still very dirty colored. I guess i need to do some each day until it’s tea colored. Next question: what should I do with the water? Is the brown stuff just rust residue? Can I dump it in the sink? Or do I need to dispose of it some special way?
Thanks for the video. Very informative. We have this device for our boiler and I was wondering if you know if it is bad for the switch to kept on the "On" position for an extended period of time? We have an auto feeder attached, but we installed a flip switch to keep it off during the summer. However, this means the switch on the low level device will be in the "On" position until we fill the boiler. Do you know if that will wear our that switch in your video?
It shouldn't be a problem. Generally, it is the "cycling" of the mechanical switch that wears it out. Are you losing water from the boiler over the summer? Do you have hidden wet returns?
New sub here. I was smelling a plastic chemical smell in my basement and noticed the tube was not showing a water level so I shut down the boiler. I have an automatic feed that has been working but not sure why the tube was dry. Bypassed the auto feed by way of the ball valve and filled the boiler to a little over half on the tube. Flushed the LWCO till the water was light brown. Now I am worried I might have damaged my boiler. Is there a way to test my LWCO float and switch? It is the same as the one in the video.
It seems you had a failed #67 not shutting down the burner when it should. When you flush the LWCO while the burner is running, the burner should shut down (it should also ask the feeder for water, but that is a convenience for you, not a safety issue). I would check to see if the float is stuck. If you cannot free the stuck float, I would not operate your boiler until you can replace the control. Difficult to tell from here if you have damaged your boiler, but if it is still holding water, that is a good sign.
@@gordonschweizer5154 thank you. Yes the boiler now shuts down when I flush the LWCO and comes back on after I close the LWCO. There is also a lot of sediment in the sight tube and corrosion on the outside so this week it is warming up and I am going to try to replace the sight tube and connections. What do you suppose the plastic chemical smell was. That is what worries me the most. Thank you
@@Peter-976 Very glad to know the #67 is working as it should. As to the plastic chemical smell, it is difficult to say, but perhaps it was the wiring near the gas valve (?) that got overheated as the water boiled away. All wiring for your boiler is exposed for inspection?
@@gordonschweizer5154 Yes mostly runs behind the front cover. EG-11 two pipe steam boiler installed in 2005. New LWCO installed about 3 years ago. It is a 67.
@@Peter-976 Good that the #67 is relatively new. I'd see if you can get a look at those hidden wires. Check if any plastic part looks melted. That might have been the source of the burnt smell. But, overall, It seems like you avoided a total loss. Check that #67 every week, and be ruthless in fixing leaks that can cause rust build-up in the #67.
Not sure of your situation. You are likely to need to scrape the rust out of the inside to free up the float for starters. I would replace the original valve type with an aftermarket type called a "dirt pocket". Here's a link to a video on that: th-cam.com/video/sGUtBz4b-oY/w-d-xo.html
I was glad I found this video, today I had issue with the exact model, the bottom 2 terminals were stock closed ,while the top 2 terminals stayed open , any part number to replace the switching part would be appreciated, & does the float need replacment ? i appreciate the video.
Did you make sure the float isn't stuck in the down position by rust chunks on the side? Can you hear the soft caused by the float moving down then up when you operate the drain the 67? It might be worth it to investigate getting a probe type LWCO. A new #11 (309100) switch is expensive.
@@gordonschweizer5154 I didnt check the float yet its model 67, I would say theres 2 screws on the side of the switch ,once removed switch should pull out with float ? buying just the switch is it cheaper?, if I go with the newer models , I would to slightly repipe around sight glass.
Remember, I can't see what you see. You can remove the switch and try to move the float linkage by hand...maybe. If the float is stuck, un-sticking it may get you going. The float might be bad, but trying to replace that could send you down the rabbit hole (don't ask me how I know...) It may be a bad switch. I can't tell from here. What happens when you try to drain it? I really don't like the 67 because it is an obsolete design that kills more boilers then it saves.
I caught my boiler before it dry-fired today, i have an older style 767 which is not working. Do you think i should replace with another 767 or go for a probe type??
So glad you caught it! Whew! Replace with a probe type if you can. Make sure the probe is at the proper level. That's hard to advise from here. Also consider adding a back-up LWCO.
@@jackmansoura Get rid of the 101A feeder. It's junk. Replace with a Hydrolevel VXT. As the what LWCO, you could see what your local supply house stocks, as M/M or Hydrolevel both work. It sometimes depends on which control better fits in the space. A remote probe with a connecting wire with the control mounted elsewhere is an option. Please get the right voltage controls either 120v or 24v. There are a lot of variables. This is by no means a complete list of options (except the VXT!).
Generally, on "package" steam boilers, the LWCO is picked out by the manufacturer and to swap it out with another type may void the warranty. Many smaller steam boilers now come with the Cyclegard installed on the block. I was told by the folks at Hydrolevel that since boiler manufacturers started doing that, warranty claims for burnt out boilers declined markedly. Love it or hate it, the Cyclegard LWCO is here to stay for a long time.
The instructions *used* to say blow it down once a month, which meant it might get done a few times per year, If you can replace your #67 with any probe-type LWCO, even the maligned Cyclegard, it would be good.
The cost of parts for this unit are too high. Still cheaper than a new boiler, however, if this unit fails. If the #67 needs parts, its usually best to replace the whole unit with an electronic probe type low water cut off, if possible, as this unit has been obsolete for decades. You may need a pro (good ones willing to do that work competently are not going to be cheap). Flushing properly is a straight-forward and there are videos on that, I believe. It should be done once a week while the burner is running so you can verify the burner shuts off when the chamber is drained.
A percentage of the cost of these pieces of crap are to pay for the platoons of lawyers needed to fend off the lawsuits of folks trying to recover the costs of boiler replacements when these fail and burn up their boilers. Or so I have been told.
@@gordonschweizer5154 Your disdain for these hollowed contraptions slips through your excellent presentation of their inner details. Remember that they were of another age, when things were mechanical things were cared for. I always loved the 67 and the 47 and they've been very good to me. But I only put them on well-maintained and properly piped boilers and take good care of them. I've seen some real disasters too... Dimwits used to install them too high, so they'd flood the boiler each time they fired. Seen hundreds like that... Great reading another experienced guy's views of these things. I don't like electronics, but I suppose these things are actually 𝘵𝘦𝘮𝘱𝘦𝘳𝘢𝘮𝘦𝘯𝘵𝘢𝘭 𝘥𝘪𝘯𝘰𝘴𝘢𝘶𝘳𝘴 these days. My, how the years pass.
It depends. If all of the control voltage is 24v (usually gas fired), then there is a step down transformer involved somewhere in the circuit to go from 120vac to 24vac. If the control voltage is all 120vac, no transformer is needed (usually a power burner gas or oil). In some cases, the shut-off control circuit is 120vac, but the water feeder circuit is 24vac (not a good idea to mix and match different voltages in the same enclosure).
Thank you for the excellent information and your special dedication sharing your valuable Knowledge and experience in the steam boiler.
@@soldelosandes. You're most welcome, and thank you for your kind words.
Best video on TH-cam about this particular type of low water cut off. Thank you
Wow, thanks!
This is the best channel to learn about steam on youtube. Great video.
Thank you for your words of support!
Every heating season I see at least one boiler cracked because the LWCO was sticking and keeping the switch closed when the water went low. If the LWCO doesn't shut the burner off when I open the blow down valve ; I always run a stick of tubing up through the blow off valve and work that float up and down until the switch is responding immediately. I always show the home owner how it works and why it is so important to flush and check it. If the #67 is real crusty, I sell them a new one. I tell them it's about $1000 for a new LWCO or $10,000 for a new boiler. The electronic feeders fail as well. I'm a firm believer in two LWCO's on a steamer, since I've seen so many of them fail. This is a good video to show to a customer when I come across a flakey #67. Thanks for the videos you make, Gordon.
Thank you very much for your comments!
$1000? 😆
@@guzman9011 The part, discounted is $550 to the trade. American Iron isn't cheap any more.
Between your videos and My heating help website I’m learning a lot , when I start in this trade i was blind but now I’m understanding more and more every day, I’m a hvac tech/ installer but in the winter we do a lot steam and hydronic boilers also we do high efficiency boilers, thanks for your videos sir
You are most welcome, Sir.
I appreciate your words and more importantly, your desire to learn!
The day you have stopped learning is the day you have died.
These videos are my way of paying back to those who helped me and to those who are still helping me.
Hello and good morning, I just happened to find your show after another HVAC show. Your show is very informative and informational on steam components.
Thanks to this video, I was able to easily unstick one of these floats and get my boiler working safely again!
Thanks Gordon!
Excellent!
Thanks for the demo, your dissection skills are awesome.
Thanks! But It's mostly due to these new diamond cutting wheels for angle grinders being readily available in home center stores.
Excellent video on demonstrating the device, thank you!!!
Glad it was helpful!
great video, I have one of those on my boiler presently and it is working fine. now I know how it works. thank you. The float switch on mine is square/cube.
Glad it helped. Keep a close eye on it. Don't let it burn up your boiler.
Hello Gordon, Wow....thank you for all the points mentioned above!! I will have to find a good technician in our area and have him look into this. I have a feeling that it might be the delayed ignition, but again I will have that looked at as well. I'm thinking it may be the ignition because the smell of gas seems to be present only when the boiler starts up. Thank you again.....Ornelio from Stoney Creek, On.
Very good video. My water has plenty of deposits. Always attacking my low water cut off. This year I didn't clean off my float & check the switch. So my aquastat paid the price for the high temperature. I'm lucky it could have been worse. I drain it very often. It just needs to be cleaned every year. Tiny dozen screws are tedious
Thank you for your comments!
Glad you didn't lose your boiler.
"Tiny dozen screws are tedious" indeed!
It's worse when they break!
Thanks,did not know there was a better replacement and the name of the better replacements,have struggled trying to take two and make one and then could not remember which way to place the top unit towards the flow..But your video showed me which way to place the top part back on,thank you so much??
Glad I could help
Great demo.
Thanks!
Great education you've given us. THANK YOU
We have this unit and when I blow it out (weekly) it triggers the refill but last two weeks it doesn't stop filling until much higher in the sight glass than previously. A gentle tap and the fill stops.
I figure the float is getting stuck. Is opening the little bolt (where you mentioned the little piece of cardboard) and digging around with a pipe cleaner a good first step?
I would open up the 1/4" hole at the top of the unit (you may have a pigtail & pressuretrol threaded in there).
Don't forget to drop the water level first to just below the hole!
Next, I'd poke the float with the sight glass protecting rod - push and release several times.
You should hear the clickity-click of the switch.
That should free up the float.
At least for awhile.
Others have suggested on this thread that you should take apart the unit by removing all those screws and pulling the float.
Then, you can thoroughly clean the inside of the #67 of all of the rusticals.
You will need to completely remove the old gasket & install a new one.
I would consider replacing the #67 with an electronic probe-type LWCO if you can.
What type of feeder do you have?
I would replace it with a VXT instead.
The problem I'm having is the part that's rusted is leaking. Some how my radiators over flowed and we shut system down. Do I need a new boiler or just clean inside to release float ?
Nice Vid.. wondering why mine doesn't have that pigtail?? Working with a Thatcher from who knows when it was installed...
Is there a 30 psi gauge mounted somewhere else on your boiler?
Awesome video. I was wondering if you could go more into detail about the wiring of that device you show at 5:20. I need to know more about the electrical connections.
Thank you!
That switch is shown sideways at first (sorry!) To your left, you should see the word "top" and the numbers "1" & "2".
Those are where you wire the burner circuit to. The bottom two terminals are where you wire in the water feed circuit.
When the float is up, the top terminals are "closed", that is they can conduct electricity, and the burner is allowed to fire when the t-stat calls for heat and the other limits are "closed".
@@gordonschweizer5154 Thank You
@gordonschweizer5154 Is there a way to trigger a call to water feeder to test if the bulb is stuck or not. If I jump the two terminals on the bottom will that work?
thank you for doing this excellent show and tell.
You're quite welcome.
Great video , Thank you !!!
You're welcome!
great video very informative. if the boiler wont turn on unless I touch 2 wires from the switch together does that mean i need to change the switch or the float area needs to be cleaned out? or is it best to change the whole thing?
When you operate the flush, can you hear the "click" of the switch operating? If not, the float might be stuck in the down position?
If the "click" is heard that might mean the float is operating but the switch is bad.
The instructions say if over 10 years old, to change the whole thing. Your call. If you go that route, I'd look into switching to a probe type LWCO
Hi Gordon my name is Steve I have watched many of your videos and thank you for making them. You are very knowledgeable about steam and I am not but we are learning. What I'm in desperate need of is my boiler has a McDonnell & Miller mechanical water feeder on it. On top of the manual water feeder is a McDonnell switch. It is a TYPE 2 switch looks like many years ago someone had made a plastic cam to control the switch? Well over many years that plastic has failed now. I'm sure there is a replaceable part for it but I cannot find it. My steam boiler is over 75 years old and still works good as long as we keep water in it. I am trying very hard to get the automatic water to work right, and most of all the low water switch to work again. Hope you can help me out thank you keep up the good videos. Steve in Wyoming
Thank you for your kind words!
I could well be wrong, but it sounds like you may have a McDonnell & Miller #47-2 low water cut off and feeder (the 2 in 47-2 stands for...wait for it, yes, your #2 switch lol)
I have a few videos on this contraption.
To say it is not my favorite control is an understatement.
Look up the #47-2 and look at pictures and parts break-downs online.
That should get you started on getting it fixed.
Definitely concentrate on the low water cut-off part of the show!
I would consider by-passing the mechanical water feeder part and going to just manual feed to add water.
If that is an issue, then I would beg you to consider to have installed a modern water feeder such as the VXT by Hydrolevel.
@@gordonschweizer5154 Thank you for steering me in the right direction. I found the part that I needed on eBay and it is on its way thank you again and keep up the good videos they do help a lot.
Great job explaining how the #67 LWCO works. I believe my float is stuck on my LWCO. The entire unit was replaced 3 years ago. Is there a gasket or something I need to worry about if I remove the float for cleaning? Also, while the float is out, should I try to insert a brush to remove some of the buildup of rust...or just leave well enough alone and don't go poking around in there. Thanks for your advice.
Sorry to hear that your three year old #67 is acting up.
Yes, if you pull the float, there is a gasket that might need to be replaced. Any plumbing supply house should be able to get it for you. Please note that there are also about a dozen screws of various lengths and types that will need to be kept track of if you remove that float assembly. Truly a masterpiece of design (sarcasm).
Once the float assembly is removed, you can chip away at any rust. Its basically a hollow shell at that point.
If your #67 is rusting up that badly after only three years, you might be taking on too much fresh water due to leaks or your water is very acidic.
Before you go through all that, make sure its not the switch that is acting up. An ohm meter will help with determining that. The switch is much easier to replace if needed (but they are not cheap).
If you can, I'd see if you can replace your #67 with a probe-type LWCO. Fewer maintenance issues, no weekly blowdowns, and and a more reliable safety control.
Thank you for the explanation. It's informative.
You are quite welcome!
Outstanding video, thank you.
Glad you enjoyed it!
Not the best practice but I have soldered that top “tee” compression fitting when I was in a jam to stop a steam leak, just food for thought
I hear ya! That joint leaks all the time. They should have used a proper mip x compression joint in the first place.
Great video. I put in a new McDonald Miller switch (#11). The auto feed stops when the float is parallel to the floor - the water level in the glass tube is about an inch. The glass tube is about 4 inches. I would have thought that maybe more water will fill from the auto feed, but stopping when the float is parallel seems right. is it?
Jeff
Thank you for the kind words!
What model auto feeder do you have?
@@gordonschweizer5154 Gordon, I have a McDonnell & Miller Uni-Match WFE-24 Universal Water Feeder. regards, Jeff
If they filled when the water line dropped only a couple of inches, the boiler would be overfilled when the condensate returned after steaming. Some systems return condensate slowly.
is there a gasket set available for this unit ? I would very much like to open it up and descale it so that I can continue to use it. iT HAS BEEN VERY DURABLE
Check SuppyHouseDOTcom. They should have them.
Hello Gordon, I want to thank you for all your help in the past. Very much appreciated! I have another question. Why would you smell gas when the boiler starts up. Is this normal or? My furnace installer said that it is a normal occurance. I would appreciate your input. Thanking you in advance. Ornelio from Ontario
You are most welcome.
As to your concerns, it is difficult to give much useful advice as I cannot be present to observe your system.
But did the tech to a combustion efficiency analysis on your system, checking especially for CO?
Did they "clock the meter" to see if your unit is overfired? Check draft/chimney? Observed delayed ignition? Leak on pilot tube?
If not, I'd find another tech who will do these proceedures.
If they did these things, and there is still a gas smell, is the boiler sooting up? Is make-up air to the boiler ok?
are questions that might be addressed.
Very helpful 👍
Does M&M #67 LWCO send a signal to automatic water feeder when the water is low? If so, what's the purpose of the M&M probe type LWCO?
Both the #67 and any probe-type LWCOs have provisions for sending a feed signal to an automatic water feeder when the water level gets low.
The water feed request is a convenience only and not a safety device.
The only true safety purpose of ALL types LWCOs is to shut the boiler's burner off when the water level in the boiler gets too low.
The probe types work pretty well with reasonable maintenance.
The float types require lots more maintenance and have a much higher rate of lost boilers due to burn-outs.
@@gordonschweizer5154 good to know. My boiler has both #67 and probe type LWCO and my automatic water feeder started working again. I wonder if it was because the float was stuck. In another thread, I was asking if there is a way to trigger a call for water by jumping the terminal? This way I can test that water feeder is still working but the float is stuck.
Mine started leaking out of a pinhole in the back by the electrical connections. Are these difficult to replace?
Possibly.
It depends on being able to remove several small screws that are prone to breakage.
Then, you'll need the proper gasket and float/bellows part.
And maybe a new switch, too.
Or,
Chuck the whole #67 debacle and install, or have installed for you, an electronic probe type low water cut off.
Its possibly more trouble and costly, but much much more reliable.
Gordon,
I recently had an issue whereby the float was stuck. I opened the valve and drained the system and the boiler kept running. I drain it weekly in the winter months. What is the best way to clean that chamber? Is pushed a brush up there with the ball valve ope and it worked but not sure I cleaned well enough.
I am so glad you discovered the infamous #67 stuck-float-burner keeps-firing *before* disaster struck.
Seems like you cleared the fault.
Keep an eye on that water level & keep flushing & testing it weekly.
If your boiler is not that old, consider having a probe-type lwco installed.
Thank you, the boiler is about 25-30 years old.
Ah, it might not be worth it to convert.
Keep a close eye on the #67.
@@gordonschweizer5154 Thanks for your help Gordon not sure the plumber I use will know how to convert it
WOW! YOU’RE MY KIND OF TEACHER.
Very kind of you to say.
Thank you!
Thank you for this info. Could you comment please on this question of mine?
I have the PROBE type Low water cut off, currently on my new steam boiler. This PROBE type LWCO, does not have any way of "blowing down" this boiler, like the old #67 did. Should I have a #67 LWCO installed, on my new boiler?
I am worried, that because; there is no "blow down" feature available on the
PROBE TYPE LWCO, that I now, will NOT be able to rid sediment and dirt from my new boiler.
YOUR input on my concern will be appreciated greatly.
You should not need a #67.
No one needs a #67 anymore.
The probe type LWCO is superior, but only provided the installer of your new boiler read, understood and followed the instructions that come with your boiler for cleaning your boiler properly, forever eliminating the need for weekly blow-downs.
Cleaning the boiler properly within the first weeks of operation is the important thing.
Hi Gordon, your videos are very useful for the handyman landlord. I'm thinking about changing the float in my 67. Should I use a sealant with the gasket?
The only "sealant" I'd use in that case is a thin smear of "anti-seize" grease maybe. Use a bit of it on the screws, too.
Hi there. When I drain it, how much should I let out of my boiler? A gallon? A bucket full?
Short answer - less than a gallon per each opening of the drain valve.
If you can, the boiler should be firing while you drain so you can observe it shutting down and then restarting when you stop draining.
That is Very Important!
What should happen when you first open the drain is a sudden rush of rusty water and then the flow should slow down. Shut the valve at that point and wait a few beats to allow the chamber to refill.
Drain again.
Maybe drain a third time. The water flowing out should get to a "weak tea" look after a few drainings.
That may be a bucket full or not.
Best to Not just open the drain and fill the bucket in one go, but cycle the valve for the most effective flushing.
@@gordonschweizer5154 this is extremely helpful. We just moved in in July and this is my first winter with one of these things. (We live in Massachusetts. Have oil heat.) I don’t know how much maintenance the previous owners did on it. I drained about a gallon out and it’s still very dirty colored. I guess i need to do some each day until it’s tea colored.
Next question: what should I do with the water? Is the brown stuff just rust residue? Can I dump it in the sink? Or do I need to dispose of it some special way?
@@carolelk It should be no problem to dump it in a laundry tray/sink if you have one. It should be just hot rusty water.
Thanks for the video. Very informative. We have this device for our boiler and I was wondering if you know if it is bad for the switch to kept on the "On" position for an extended period of time?
We have an auto feeder attached, but we installed a flip switch to keep it off during the summer. However, this means the switch on the low level device will be in the "On" position until we fill the boiler. Do you know if that will wear our that switch in your video?
It shouldn't be a problem. Generally, it is the "cycling" of the mechanical switch that wears it out.
Are you losing water from the boiler over the summer? Do you have hidden wet returns?
New sub here. I was smelling a plastic chemical smell in my basement and noticed the tube was not showing a water level so I shut down the boiler. I have an automatic feed that has been working but not sure why the tube was dry. Bypassed the auto feed by way of the ball valve and filled the boiler to a little over half on the tube. Flushed the LWCO till the water was light brown. Now I am worried I might have damaged my boiler. Is there a way to test my LWCO float and switch? It is the same as the one in the video.
It seems you had a failed #67 not shutting down the burner when it should.
When you flush the LWCO while the burner is running, the burner should shut down (it should also ask the feeder for water, but that is a convenience for you, not a safety issue).
I would check to see if the float is stuck.
If you cannot free the stuck float, I would not operate your boiler until you can replace the control.
Difficult to tell from here if you have damaged your boiler, but if it is still holding water, that is a good sign.
@@gordonschweizer5154 thank you. Yes the boiler now shuts down when I flush the LWCO and comes back on after I close the LWCO. There is also a lot of sediment in the sight tube and corrosion on the outside so this week it is warming up and I am going to try to replace the sight tube and connections. What do you suppose the plastic chemical smell was. That is what worries me the most. Thank you
@@Peter-976 Very glad to know the #67 is working as it should.
As to the plastic chemical smell, it is difficult to say, but perhaps it was the wiring near the gas valve (?) that got overheated as the water boiled away. All wiring for your boiler is exposed for inspection?
@@gordonschweizer5154 Yes mostly runs behind the front cover. EG-11 two pipe steam boiler installed in 2005. New LWCO installed about 3 years ago. It is a 67.
@@Peter-976 Good that the #67 is relatively new.
I'd see if you can get a look at those hidden wires. Check if any plastic part looks melted. That might have been the source of the burnt smell.
But, overall, It seems like you avoided a total loss.
Check that #67 every week, and be ruthless in fixing leaks that can cause rust build-up in the #67.
great video!
If you replace the old cut off valve it is work or not
Not sure of your situation.
You are likely to need to scrape the rust out of the inside to free up the float for starters.
I would replace the original valve type with an aftermarket type called a "dirt pocket".
Here's a link to a video on that: th-cam.com/video/sGUtBz4b-oY/w-d-xo.html
I think the blue box in the tray is a ssc dirt pocket cap. Cheaper alternative, when combined with a nipple and ball valve.
Ah ha! Good eye! That's exactly what that was. This video was running a bit long to bring it up. 100% agree with you on the ssc dirt pocket cap.
I did that conversion on mine several years ago.
I was glad I found this video,
today I had issue with the exact model, the bottom 2 terminals were stock closed ,while the top 2 terminals stayed open , any part number to replace the switching part
would be appreciated, & does the float need replacment ? i appreciate the video.
Did you make sure the float isn't stuck in the down position by rust chunks on the side?
Can you hear the soft caused by the float moving down then up when you operate the drain the 67?
It might be worth it to investigate getting a probe type LWCO.
A new #11 (309100) switch is expensive.
@@gordonschweizer5154 I didnt check the float yet its model 67, I would say theres 2 screws on the side of the switch ,once removed switch should pull out with float ? buying just the switch is it cheaper?, if I go with the newer models , I would to slightly repipe around sight glass.
Remember, I can't see what you see.
You can remove the switch and try to move the float linkage by hand...maybe.
If the float is stuck, un-sticking it may get you going.
The float might be bad, but trying to replace that could send you down the rabbit hole (don't ask me how I know...)
It may be a bad switch. I can't tell from here.
What happens when you try to drain it?
I really don't like the 67 because it is an obsolete design that kills more boilers then it saves.
@@gordonschweizer5154 I drained it few times ,but no change in switching .
@@nykid8849 I'd hate for you to drop $200+ for a new #11 switch just to have it be a stuck float.
Thanks for the video. Very informative.
Glad it was helpful!
I caught my boiler before it dry-fired today, i have an older style 767 which is not working. Do you think i should replace with another 767 or go for a probe type??
So glad you caught it! Whew!
Replace with a probe type if you can.
Make sure the probe is at the proper level. That's hard to advise from here.
Also consider adding a back-up LWCO.
@@gordonschweizer5154 Thanks Gordon! Appreciate the feedback. Should i go with a M&M or Hydrolevel lwco? Should i keep the old 101A feeder?
@@jackmansoura Get rid of the 101A feeder. It's junk. Replace with a Hydrolevel VXT.
As the what LWCO, you could see what your local supply house stocks, as M/M or Hydrolevel both work.
It sometimes depends on which control better fits in the space.
A remote probe with a connecting wire with the control mounted elsewhere is an option.
Please get the right voltage controls either 120v or 24v.
There are a lot of variables.
This is by no means a complete list of options (except the VXT!).
@@gordonschweizer5154 Any recommendations for a model?
Would you recommend on new boiler?
Generally, on "package" steam boilers, the LWCO is picked out by the manufacturer and to swap it out with another type may void the warranty.
Many smaller steam boilers now come with the Cyclegard installed on the block.
I was told by the folks at Hydrolevel that since boiler manufacturers started doing that, warranty claims for burnt out boilers declined markedly.
Love it or hate it, the Cyclegard LWCO is here to stay for a long time.
Once a week you say....😬 lol Blew down mine and got alot of crusty gunk. Would you suggest replacing with a cycle guard?
The instructions *used* to say blow it down once a month, which meant it might get done a few times per year,
If you can replace your #67 with any probe-type LWCO, even the maligned Cyclegard, it would be good.
@@gordonschweizer5154 thank you Gordon, great content, thanks again.
Can I just restart my stove after the low water sensor
I'm sorry, but I don't fully understand your question.
gracias por su informacion
De nada
great job
Thanks!
How to flush no67 and cost of parts
Good video
The cost of parts for this unit are too high.
Still cheaper than a new boiler, however, if this unit fails.
If the #67 needs parts, its usually best to replace the whole unit with an electronic probe type low water cut off, if possible, as this unit has been obsolete for decades.
You may need a pro (good ones willing to do that work competently are not going to be cheap).
Flushing properly is a straight-forward and there are videos on that, I believe.
It should be done once a week while the burner is running so you can verify the burner shuts off when the chamber is drained.
Is anyone else amazed at what this hunk of American cast iron costs these days??
What is particularly galling is the #67 is obsolete & has been for almost four decades.
A percentage of the cost of these pieces of crap are to pay for the platoons of lawyers needed to fend off the lawsuits of folks trying to recover the costs of boiler replacements when these fail and burn up their boilers.
Or so I have been told.
@@gordonschweizer5154 Your disdain for these hollowed contraptions slips through your excellent presentation of their inner details. Remember that they were of another age, when things were mechanical things were cared for. I always loved the 67 and the 47 and they've been very good to me. But I only put them on well-maintained and properly piped boilers and take good care of them. I've seen some real disasters too... Dimwits used to install them too high, so they'd flood the boiler each time they fired. Seen hundreds like that... Great reading another experienced guy's views of these things. I don't like electronics, but I suppose these things are actually 𝘵𝘦𝘮𝘱𝘦𝘳𝘢𝘮𝘦𝘯𝘵𝘢𝘭 𝘥𝘪𝘯𝘰𝘴𝘢𝘶𝘳𝘴 these days. My, how the years pass.
Should every low water cut off have a transformer.
It depends.
If all of the control voltage is 24v (usually gas fired), then there is a step down transformer involved somewhere in the circuit to go from 120vac to 24vac.
If the control voltage is all 120vac, no transformer is needed (usually a power burner gas or oil).
In some cases, the shut-off control circuit is 120vac, but the water feeder circuit is 24vac (not a good idea to mix and match different voltages in the same enclosure).
@@gordonschweizer5154, Thank you sir, I'm much obliged for the information.