Water Level Issues

Jeff_133

Thanks Terry - Great input. I noticed that the boiler did settle down once i replaced the water - and a lot of excess sealant did go with it. However, it is clear that it is still quite dirty, and with your explanation I know understand that with a Dunkirk, I've got to keep it that much cleaner. the plan right now is to replace with a similar model, so this is important advice going forward.

Jeff_133

Water Level Issues

I have a 17 year old leaky Dunkirk steamer, 225K BTU, one-pipe steam system. I inherited this beauty when i bought my old Victorian a couple years ago. I will note that the system does have an autofeeder that works properly, and the boiler is piped per the Dunkirk specs.

I've had a number of issues this winter, but with help from this Wall, i've been able to nurse it along, ad will hopefully make it spring so I can replace it under non-emergency circumstances. My plan is to replace it with the same model, which Dunkirk still manufactures. One of the critical issues i have had has been maintaining a proper water level. i used a boiler sealant to help with the leaking, and this has helped. in the sightglass, while making steam, i've observed quite a bit if surging and backflow of water from the top of the glass gauge. so, i decided to flush the boiler, following the Dunkirk recommendation, and i put more insulation on the near boiler piping, thinking these steps would help with both of these issues. however, i am still experiencing both problems. additionally, the water level remains unpredictable. for instance, before the boiler cycles on, the water level will be seemingly correct, but once the boiler begins to steam, the water level shoots thorough the top of the sightglass, only retuning to the middle of the glass after 5-10 minutes of steaming. I'm assuming this is because the steam pressure has pushed condensate in the system back into boiler, thereby increasing the water level. At this point I get the surging and backflow i described earlier. During the day, when I have the thermostat set higher, I will check the water level between heating cycles, and at times, the sight glass is full, and at other times, it is almost dry. in the later circumstance, I do still have leaking, but not enough to explain where all the water went. so, i assume it must be stuck in the system somewhere. while i haven't observed it directly, i do hear the autofeeder kick on, so i know this works. Now, if the water level is too high, i can tell b/c i get some nasty hammer. so, in this circumstance, i'll bleed some water out, and then the system runs nice and quiet. and, for the most part (at least recently), this is how things have been going, with exception of a major leak incident that put the boiler pilot light out and put my place into the deep freeze. this is too painful a memory to explain in any more detail

I've had a number of vendors look at the system, and been told than i needed: a) a new boiler (ok, got it), b) a new boiler AND/OR a condensate return reservoir/pump added (even though the Dunkirk specs don't call for one), and c) that this boiler can keep on going, with a little more sealant (well, ok but i want to get some sleep at night).

I'm thinking the returns are simply blocked, or close to being blocked, and when the new boiler is installed, the returns can be cleaned. so, i'm trying to understand if all this behavior can be explained by my leak issue and clogged returns, or if i have bigger problem. I should mention that the main vent appears to be working properly, althouh I was also planning on replacing it at the tim eof boiler install.

sorry for the long post, but i' hoping for some feedback on what my next steps should be. I'm pretty much convinced that i'll be putting in a new boiler, but i want to address the system comprehensively, and not simply hope that just replacing the boiler will resolve everything. Thanks for reading.

Kool Rod

Hi Jeff- I'm not quite sure what to tell you as I don't know just how much your water leak/adding more water is contributing to the situation. Normally the water level in the site glass, before the boiler starts it's cycle, will be at the designed water level which is generally in the middle of the site glass. (The designed level can be determined from the Installation drawings of your boiler) During operation the water level will drop a bit but not to the level where the automatic water feeder kicks on.

The movement (surging -up & down ) of the water` level in the water site glass should be about 3/4 of an inch during normal operation. Anything more generally indicates that your boiler water needs to be "skimmed". You mentioned "flushing" but not "skimming". These are two different operations.

If you aren't familiar with skimming, Here is an article by Dan where he mentions skimming (at the end of page 1 beginning of Page 2)

http://www.masterplumbers.com/plumbviews/2002/BasicSteam.asp

I had to skim my boiler 3 different times before my boiler water finally settled down. I did it on 3 Saturday mornings and skimmed about a full 5 gallon bucket each time. Use the Search function on the Wall as there is a lot of discussion on skimming available to read.

Sounds to me like you're also having problems with your wet returns which maybe partially plugged up. Just replacing them is usually far easier/cheaper than trying to clean them.

You have a one pipe steam system! Who ever told you need a condensate pump doesn't have clue what they're doing steam wise and I wouldn't want them to touch`my boiler!

If you don't have Dan's books already (See "A Steamy Deal" at the bottom of this page) I'd highly suggest you get them before installing a new boiler. Keep in mind the the manufacturer's suggested piping is the minimal rather than the optimum. Also on your new boiler consider putting in a VXT water feeder as it will tell you exactly how much water`is being added to your boiler.

http://www.hydrolevel.com/new/index.php?option=com_content&task=view&id=50&Itemid=

If you haven't done so already, try skimming. I'm wondering about the boiler sealant you using and maybe it is giving off oils which can cause water level surge problem.

Maybe if you posted some pictures of you boiler's piping and of your returns we might see something that needs attention.

- Rod

Jeff_133

Hi Rod - Thanks for this reply.
Yes, I pretty much thought the condensate pump was nonsense. Thanks for confirming this.
You are correct, I did not skim, I replaced the boiler water, as the Dunkirk manual indicated that if the water was very dirty, to go this route first. This was about a week after I had treated it with the sealant. And boy, it was dirty. But when I did replace the water (did this a few times), much sediment came with it, and it was a just a day or two after this when I had my "sky is falling" moment, with the pilot light out and water all over the floor. My theory is that I disturbed sediment that was filling gaps in the boiler sections... so i've been leaving the poor thing alone since then, and just watching the water level, and adjusting ONLY if it's really out of whack, or I get hammer. i will say that i think the sealant did work, and is helping me get this thing through the winter.
As for the surging - this existed before i treated with sealant, and replaced the water. it's still doing it.
I have a short video - kinda grainy - of the sight glass during a steam cycle, but the wall won't let me post it. But here are some pics of the boiler piping - before added the insulation. Input welcome and appreciated!
Regards,
Jeff

Ted Robinson

Piping nightmare?

I am sure the Pro's will be in here, soon.
From my knowledge there is a missing equalizer and hartford loop, etc.
My new boiler water finally calmed down after the third skimming process which I did the 'cold' way. Iopened the top skimming port and slowly overflowed the oil floating on top of the water.

Jeff_133

see lower left hand corner of first pic for hartford loop. wet return to its left. kinda tough to see from this perspective.

Bill_110

I've just gotten a Lennox boiler, which is actually made by Dunkirk and has the exact same installation instructions. Your near boiler piping looks a lot better than mine, with the system risers being independent and coming after the boiler risers. From what I've read from Dan's works and gathered from the Lennox manual and the operation of my system, after the boiler makes steam (say after 10 minutes) the water level will drop 2 to 3 inches. As it goes through the rest of the cycle it shouldn't surge any more than about 3/4". On my setup the normal water line, when the boiler is off and cold, is about two thirds of the way up the site glass.

Funny you should mention system gunk sealing up leaks. The guys who did my install used copper even though they were supposed to use iron. The joint where the header joins the equalizer leaked right from the get go. But since they ran away without skimming the boiler system gunk worked it's way into the leaky joint and sealed it for now. So I wouldn't recommend doing a skim the way the manual states - ie heating the water while skimming. I did mine Dans suggested way - a cold skim (actually 2 sessions so far), and that definitely helped with water droplet carryover from the top of the site glass and surging after steaming. The radiators seemed to heat better after that as well. And with a cold skim you will will get the junk floating on top, and be less likely to dislodge any of the volunteer gunk that is temporarily helping to seal up your leak.

One last question which might be kind of odd, but when does your water feeder kick on? For instance does it come on during the steaming cycle or right after the boiler shuts off? Does your low water cutoff stop the boiler firing before the water feeder comes on?

Jeff_133

Hey Bill - Thanks for the feedback. What you described is what is happening here. When the boiler is triggered by the T-stat, my water level first rises through the top of the sight glass, and then after 5 or so minutes, it settles back down. You are suggesting that this something I don't need to be concerned about, correct? Under operation I get a quite a bit of carryover. The water line definitely surges more than 3/4". Can you direct me to a link for instructions on the cold skim? This approach makes a lot of sense for my situation.

My water feeder generally comes at the beginning of a cycle, in the AM (I do an evening setback). I can hear it pop on. Yes, the LWCO is working, and does stop the boiler. My theory is that during set back, as the sections cool off, the seals are opening up, and the boiler starts to leak. this, combined with possibly clogged returns, makes my water level low overnight, and then when there is a signal from the T-stat to give heat, the LWCO is tripped and the autofeeder comes on. Funny thing is that most of the water around the boiler dries up pretty quick once the boiler is firing. In fact, during normal operation, it's hard to tell i have a leak at all (except for all the scale and rust!) In my disaster scenario, the water leaks onto the pilot, the sections get real cold, and then i have water all over the floor.

question about copper piping: last year a section of my cast iron piping on one of the main runs near the boiler (not the header section) burst, and my plumber replaced it with a copper section. I wondered at the time why they used copper, but didn't really know any better. The point at which the sections are joined do not leak, but they did use a smaller diameter pipe. It was a pricey job for a 36" section of pipe. Should I be concerned about this area failing?

Bill_110

Jeff, what I meant was that as the boiler cycles and runs for a few minutes it goes DOWN 2 or 3 inches in the site glass, this represents the water that has turned to steam and gone out to the piping. At this stage the level shouldn't fluctuate much more than 3/4" till the boiler is off and the condensate starts to accumulate. If your level actually goes over the top of the site glass I would be concerned about that. I'm just a learner like you so I don't really know what to make of that. How soon does it do this after the burners fire? Maybe if your return right into the boiler is really constricted with crud the thermal expansion caused by the burners coming on creates a channel for the backed up condensate to rush in?

Maybe someone will weigh in on that one hopefully. As far as skimming goes I don't think it can hurt and its pretty easy (even I did it successfully). It helps to have a skim tapping though, which is one of the few things the guys who did my installation did right. If you don't have a dedicated skim port, it gets a little more complicated as you have to take off something else to create the port, and I'm not the guy for counseling you on that.

In the library section of this site is a link somewhere to an article in which Dan explains how to do the cold skimming. I just did a google search on the subject and actually got a link to another site which contains some Dan Holohan excerpts, with the cold skimming instructions starting at the bottom of the page. This might be quicker than hunting thru the library articles.
http://www.masterplumbers.com/plumbviews/2002/BasicSteam.asp


As far as the copper piping you got as a replacement is concerned, the consensus on this site seems to be that for areas above the waterline black iron is superior in durability to copper. If it's below the water line it doesn't matter as much. I had some guys tell me that copper pipe holds up ok. I have only limited experience, but in my copper piping job it started to leak in about 2 days, so I tend to believe the guys who say copper is inferior to black iron for steam pipes.

Some of your low water problems after the night setback might be due to more condensate formation as the steam hits the cold pipes. If your condensate is sluggish in it's return I guess this is going to make your water level go even lower and call for more water feeding action. I apologize in advance if this is a dumb question, but would it be remotely possible that your water feeder is briefly coming on and creating that surge after the boiler fires up?

Kool Rod

Hi Jeff-
I'd definitely skim as you'll find it really makes a big difference in steam quality. You wouldn't think that it would mean that much but then you have to understand what how much a tiny amount oil on the surface boiler water changes the action of the water.

On sailing ships they use to calm the waves around the ship during a storm by attaching a small barrel (5 gal.) filled with oil to a rope and throwing it into the sea. The barrel had a few small holes punched in it to let the oil slowly escape. The super thin oil slick around the ship reduced the breaking waves as the oil increases the surface tension of the water.

In your boiler, oil reacts the same way in that it floats to the surface of the water and increases the surface tension. Rather than the steam bubbling through the surface of the boiler water (like the bubbling in glass of soda pop) it now has to collect together in larger bubbles to force its way through the oily surface.When the bubble is large enough it breaks through the surface and "explodes". This bubble "explosion" causes water to be flung up into the steam exiting the boiler and it is carried along with the steam resulting in what is know as "wet steam". Skimming eliminates this and that's why skimming is so important.

This increase in the water level when the boiler starts up rather has me perplexed. I can't think off hand what would cause it. After looking at you pictures, I am wondering about your Hartford Loop. (See attached picture) The items: "A",the Header, "B",the Equalizer, and "C",the Boiler Return, form the Hartford Loop. The "Wet Return","E", is then attached to the Hartford Loop with a close nipple at Position "D".

The question is: What is "X"?

If it is a Wet Return, it should be attached to "E" as all return condensate is supposed to enter the Loop through the close nipple at Position "D". From the photo I can't determine what exactly "X" is/does. Also is there anything else attached to the Loop? I am just asking as there seems to be a tee in the far right lower corner of the loop.

I'm wondering what affect, if any, does "X" have attached at the present location - on the system -on the water level when operating?

- Rod

Jeff_133

With regard to water level on start up, yes, mine goes UP not down. This happens as soon as the water gets up to temp, and the boiler just begins to steam. What you say for proper operation makes total sense. I hadn't thought of the thermal expansion idea, but I suppose this is plausible.

With regard to skimming, my boiler does have a 2 1/2 tee off the main riser that has a plug for skimming. You can see it in my pic coming out of the the right hand side of the boiler. I read the article you reference, and it says to attach a 6" nipple - would I need to do this, or can i let the skim run right out of the open plug from this tee?

With regard to the copper piping - thanks for the added detail. It is in a steam area, but it is working OK. I suppose next time I will insist on iron.

Lastly, no, the water feeder isn't coming on after the boiler fires up. Additionally, the surge I am seeing happens regardless if the water level is low or not. It might be lower (but not low enough for the feeder to be triggered) and the level still shoots up through the sight glass when the boiler turns up, and then settles back down after 5-7 minutes of operation. I'm pretty confident the whole LWCO/autofeeder mechanism is working as it should.

Thanks very much for all your feedback. It is helpful!

Jeff_133

Hi Rod - Thanks very much for your labeling! Very helpful! No, X is not a wet return. It is just a continuation of the equalizer, and is capped vertically near the floor.

The tee I think you are referring to in the loop (just to the right of you label C) is a tee for a drain plug. You can't see the drain plug itself, because it's obscured by the section of C that comes back towards the close nipple. This is the drain I used when I replaced the boiler water.

I am all for giving the skim method a shot. As I mentioned in my reply to Bill's last post, I could use a little more guidance on what to attach to the 2 1/2 tee on the main riser in order to skim properly.

Bill_110

Jeff I have the same type of skim port and in my case I just let the water trickle out at a very slow rate. It might work even better if you used some kind of reducing fitting that narrowed it, but I seemed to get pretty good results just using the port as is - for me surging was reduced and the water droplets trickling from the top of the sight glass seemed to stop. I just turned down the water feed as low as I could get it and still have it run out, and did it for 3 to 4 hours each time.

Kool Rod

Hi Jeff-
Okay, Thanks for straightening me out. From the picture I was a bit confused on your Hartford loop.

Attached is a picture of a skim port coming off the riser on a boiler similar (but bigger) to yours. Use the same diameter pipe coming off the tee and then reduce it, after the elbow, on the down vertical. I have something similar on mine. After the ball valve, I close off the open end of the valve with a short nipple and a pipe cap when I've finally finished the multiple skimming operation. This is just as an added safety precaution in case a child or some idiot plays around with the valve when the boiler is operating. Make the down leg so a 5 gal plastic bucket can easily fit underneath.

Skimming - When the boiler`has cooled down, open the skim port ball valve and then very slowly open the manual fresh water feed until the water runs out the skim port. The water should just S-L-O-W-L-Y trickle out the port. I filled a 5 gal bucket in about 2 hours so that should give you an idea as to the speed. I did 2 hour skimmings on 3 consecutive Saturday mornings to get my boiler water clean and having to do seven consecutive skimmings is not unheard of. Be sure to adjust the water`level back to the proper operating level after you finish each skim.

Copper piping - Here are some comments on copper by Brad White and Gerry Gill, two of the "Super Pros" who are on this website.

http://www.heatinghelp.com/newPages/pdf/32_43_58.pdf

I have copper on my system but it is just used on the wet returns. While black pipe is preferred, copper seems to be pretty common on the wet returns on a lot of the pro installations. It is mainly the steam side of the system where copper is a definite "NO-NO".

- Rod

Jeff_133

Hi Guys - Thanks for the great input. I think I've got a clear idea on how to proceed with the skim process and will try it out in the next couple days. Hopefully, this will calm the sucker down. And if nothing else it will be good practice for when I replace the boiler once the weather breaks. I am hopeful that most of my issues are related to the cleanliness of the boiler water, and my supposition that the returns are clogged. An don the second point, I will have to wait until spring as well.
Thanks again, I really appreciate the guidance!
Cheers,
Jeff

Saxon22

water Level - a disappearing act

I have a stem eating system and it has worked fine till this Saturday. On that day, I decided to take off my old tiles in the boiler room/heating room. There was some banging but nothing super major. the job was done but now my heating system is going crazy. I used to regulate the water level about 2 to 3 times a week adding as needed. Now since Sunday, I Have to fill the tank 95% (I do that before I go to sleep) and by the morning the tank is empty. Where is the water going?

Supply House Rick

disappearing water

why not start a new thread so your query will not get lost.

by tiles, i suppose you mean floor tiles? do your return lines flow under the floor? could a rusty pipe under the floor have been punctured? if they were underground, could they be replaced above ground?--nbc

ttekushan_3

Dunkirks

have very narrow sections and fairly small water surfaces. The lower weight and mass works to advantage during fall and spring months, but steady state efficiency is not all that impressive. It all seems to even out by the end of the season, though.

The narrow passages have a downside- NOTHING can be allowed to contaminate the boiler water... As a matter of fact, the Dunkirk is one of the few boilers that doesn't tolerate any more than the tiniest amount of pH regulating and oxygen scavenging water treatment. This also includes many brands of leak sealers, unfortunately. The excess leak sealer will take a month of sundays to get out of there.

I usually wind up doing the cold skim and alternate with a surface blowoff while the boiler is steaming. You have to have a proper nipple and valve on the skim port and a hose that can withstand some temperature and direct the output into a drain. It will be hot and steamy, but the surface contaminants will exit this way. The valve should be opened to a level that you and your drain will tolerate. It can still take quite a while. I usually leave the valve cracked partially open so that I can leave it while the system operates normally. If you have children, etc, this is not a good idea. Get out the lounge chair, a bright light, some Hawaiian music, a fake palm tree and enjoy the warm balmy afternoon. If you're so inclined, one of those drinks with the umbrella in it would be appropriate in this setting.

Good luck.

-Terry

Saxon22

Water is gone

After some research,it seems that by taking of floor tiles I probably destroyed the pipe that brings the water back to the tank. The house was built in 1930 so I cannot blame anything or anybody.
No plumber has yet to loo at the situation, but over the phone, all three gave the same diagnosis: Broken pipe.
Now it seems there are 2 options:
Option #1: destroy the cement, get to the pipe, take it out and put a new one. Plenty of work and I imagine plenty of $$$.
Option #2: run a new pipe above the floor and save the headache as well as money in the process. we will see which one is the best option.

Thanks for the help guys.

Supply House Rick

sooner or later

it would have happened even without the tile work. as you said, you were adding water 3 times a week, and i think that shows the pipe was already rotted out. if you can replace it by running it above ground, you will get an extra 30 years of life out of it.--nbc

Saxon22

Funny

Funny, I was thinking that by putting a new pipe in the cement would keep it healthy longer than having it exposed. I guess I was wrong. Since having it run above the floor provides 30 years extra (my boys are happy to hear that, as for me I do not think I am going to be that lucky to be around in 30 big ones, but I digress) I think that it would be the way to go. My tank/heating system is on a pedestal around 10 inches above the floor level so I presume that much height would provide enough room to run them above the floor?

Or are there other considerations?

Supply House Rick

pipe height

have the new pipe supported on bricks, resting on the floor. you want that return as low as possible, and to drop straight down from the dry return to the 1st. brick. put in some unions so you can make changes later if needed. while you are at it, as well, leave provision for the proper main vent installation on the dry return, off-set to protect against water-hammer. if you can hold out until warmer weather, this would be a possible do-it-yourself project. if you limp along, filling your boiler every day however, you run the risk of accelerated corrosion, because of the extra oxygen. maybe filling it from the hot water system would work to reduce that.--nbc.

Saxon22

I wish I could

Your advice is appreciated but it is all Greek to me. I wish I were that handy but there is no way I could do this on my own. I will wait for my tax return and then try to permanently fix it. I have no idea how much it would cost me (and I hate wasting people's time asking them for an estimate if I am not going to do it right away.
As for the hot water, that is how the system is build, that is the water to fill the tank comes from the hot water tank.