No Heat on Some Rads One Pipe Steam

CWS

I have a one pipe low pressure steam boiler that is heating well except for the last 2 risers on one of three circuits. It seems to run out of steam before it gets to the living room and kitchen rads. The living room does better than the kitchen but it is is closer or upstream on th emain so it gets a little heat before it runs out of steam. There are 3 floors that have one rad on each floor that runm up from thej basemnt main. Here is how I checked the system. Outdoor temp was 70 degrees. Customer complaint was little to not heat on living room and no heat on kitchen rads. Says he has been there 5 years and does not remember those rads ever working. First thing I did was check the vents. 3 dry returns at the boiler from 3 circuits. All return vents good and sized right. I broke the union to the return to see if I could get steam and or condensate. Ran boiler to aprox. 2 psi ( gauge filled with mud. Cleaned and not responsive. No gauge on truck) There was no steam at the dry return at the boiler. Small amount of conensate (aprox. 2-3 oz per minute. Very cool water. Next I inspected the circuit to see if I had water trapped in any sags or poor pitched lines. I drilled in 4 locations and I got a decent amount of water out of the first part of the main where it starts and it improved a bit but still no steam to the last 2 risers on this circuit. I drilled a tap near the last riser that goes up and feeds all three floors for the kitchen rads and I left it open while running the boiler. I could not even get a hint or puff of steam at this location. My thoughts were that where the main comes out of the header has a offset that was taken off the bottom of the main rather than the top and somehow this is restricting the amount of steam volume that I am getting in that circuit due to condensate. I plugged the other vents in an attempt to get the steam to go through this problem circuit and this did not help. I checked the steam main valve but it is stuck. I imagine it is fully open (could not tell by looking at the stem) because the other circuits heat fast 4 mins from cold start. I thought it should be able to heat this circuit even if it were partially closed. Water line was within 1/4" from the top of the glass. Seems high but again has no effect on the other circuits making steam fast. Normal movment in glass (no severe bouncing). Thought that the boiler might be too small but at 70 degree ambient and other circuits limited by plugging mains it should be blasting steam out of the return I opened and the holes I drilled. Thought about a vaccum but the holes agian would be a vaccum breaker. Tried to power flush and I attached a hose bib and stuffed a rag at the return near the boiler. Filled and removed rag to allow fast drain...water seemed cleaner than when it went in. Please help! Do not know where to go from here. The holes at the beggining of the circuit where I drilled holes plumed some steam that seemed what a tea kettle on the stove would produce. About 10" and low pressure. Makes sense that it was running out of steam due to low volume of steam. This is a 13 unit building and it almost seems as there is a total restriction in the main that feeds the circuit I am having problems with. .Here is what I have. Peerless 211-6 which is a 10 burner, and I think 6 section (not sure on the section #) I called and local Peerless dealer was not sure on the outout of this boiler. Need help on where to go next. Thanks

Steamhead

Fill the boiler up well past the sight glass

and see if water leaks into the firing zone. Your problem sounds like there is a hole in the boiler above the waterline, if so this will tell you. Be sure to do this when the boiler is OFF and COLD, otherwise you might crack it.



If you don't find a leak, bring the water level back down to its normal point before running the boiler again.

CWS

I do not think that is the issue.

The capicty is there. It heats 13 apts with no problem. I took those off line or at least decreased the capicty by plugging the main vents and it heat outstandingly well and quick. I do not believe capicty is the issue or pressure drop or both. I should add that if water were building up in this main takeoff that comes from the bottom near the boiler header I should ge some water hammer like i never heard. I do not get ANY water hammer out of this boiler throught the heat up process from beginning to end....NO HAMMER. By the way I did a visual at the outside stack when I first arrived and saw no sign of steam I know this is not how to check) but just for the record. I seems that even if by small chance something fell in the supply it would still allow enough steam to get through to give me some sign of pressure at the end where I am having problems (where I drilled a hole) even if it were a small hint. Seems an obstruction would still give me some steam pressure. It is almost like someone stuffed a rag in the main before it gets to the radiators. I do get enough heat to heat about 4 risers before it runs out of steam. Thanks for the input.

CWS

Look At the Pic of the takeoff in the 2nd Pic

This take off is at the bottom of the riser near the boiler. Is this my problem? It is at the bottom of the supply riser where it comes off the boiler header about 4 feet away. I was thinking that when the steam enters this pipe at the bottom it is getting rained on with condenstate and saturating the **** out of my steam. If this is the case thou I thought I would hear hammering like the pipes would sound like they were being beat on with a 50 pound sledge hammer. there is no hammer what so ever. Could it be that the steam is so close to the header that it has not picked up enough velocity or latent heat to get any hammering out of it. It does seem to be very lazy steam like it i sbeing showered with condenstate at this point in the pic and taking all the heat out of my steam. Perhaps it is turning back into steam and that is what I am seeing down stream? Just wondering if this is on the right track why no hammer?

Greg Maxwell

Steam Problem

My first guess from looking at your piping is that is has never sorked quote right. First thing you should so is check to see if you have the 24" needed for dry steam. It looks like you could be carrying a lot of water into that leg, and possibly, that line is plugged. You may have to redo that tee to the proper take off with the riser.

Rod

Steam System Problems

Hi- I must first state that I’m a homeowner and not a pro. Steamhead, who is a very experienced steam pro, suggested that you may have a hole in the upper part of boiler so I would check for that first by doing, as he suggests, flooding the boiler to the top and waiting to see if a leak develops.  It’s too bad the king valve is stuck as you could , with a properly working pressure gauge,  then shut the king valve to check if the boiler is able to build pressure.

     I was attracted to your pictures as I have a Peerless boiler myself. One of the first things that struck me, if I’m reading your pictures correctly, was that your boiler risers are opposed with the steam riser coming off in between them. This goes against both the I&O manual and common steam practice and would indicate that the original installer wasn’t very competent. Just out of curiosity I looked up the I&O manual for this boiler and it clearly lay out how the boiler should be piped.

Here is the link if you need a copy:

http://www.peerlessboilers.com/DesktopModules/Bring2mind/DMX/Download.aspx?EntryId=85&PortalId=0&DownloadMethod=attachment



With the original installation done by an installer who appears to be of questionable competence, I would think your best bet is to refer to the I&O manual and do a complete survey of the system as you may find other piping configurations that aren’t correct. The present configuration has to be affecting the volume and the quality of the steam produced.



On the riser coming off the bottom of the steam main- The only place I have run across this was when the riser was dripped. (See attached picture from Page 3 of the Burnham Heating Helper) Is there any sort of a drip connected to this now or indications that one has been removed?

As this boiler seems to be suffering from long term lack of maintenance it would seem to me that the issues are:

1. Boiler integrity - finding out it it will hold steam.

2. Safety issues- like fixing bad gauges and possibly inoperative controls and safety devices.

3. Correcting improper piping configurations, both on the boiler and the steam lines.



So much for my 2 cents. Hope this is of help to you.

- Rod

CWS

Drip Leg

This brings up a good point that I overlooked. The header does bullnose which would cause problems with wet steam. I am putting my check list together before I return and will replace the gauge. At this point I will check the boiler for leaks as suggested, I am merely think out loud not discrediting his approach. I think it is a great idea but I just mentioned  that I thought it might be attributed to some other area due to the fact that it looks as if the original installer cut coners. There is no indications of there being a drip leg off the bottom take off from the steam supply. Is it possible to run a drip leg off this portion of pipe assuming that this is the problem? This building owner makes a 2 hour trip to get me in the mechanical room so I am getting my punch list together. If I am making wet steam at the header it seems that this is the area that I should be looking at closely. Combined with the takeoff from the bottom of the main and this is a heavily saturated condition. Any thoughts on how this can be confirmed and or corrected? Even if a leak is confirmed when I test for leaks it will not explain why I am able to heat the other 60% of the system in under 10 mins to blazing hot return temps and when I isolate this small little circuit it will run for 20 mins and I get absolutely no pressure from the end of the main where I drilled the holes. So in the event that a leak is confirmed I believe I should be looking for other problems as well that are more than likely the main contributors to the extreme delta on this circuit.

CWS

Dry Steam A Demension?

By the way the A Dem  is 33" to the bottom of the header and 58" to the bottom of the steam supply pipe off the header. I used the 33" for the A Dem is this correct? I have always used the bottom of the header as my measuring point, Is this correct?

ChrisJ

incorrect

You want at least 24 inches from the water line to the header.



You maybe pushing water into the header in significant quantities which is causing really wet steam.

Jamie Hall

Got to admit

I really don't like the idea of a takeoff going off the bottom -- or even off the side -- of a steam main.  That is almost guaranteed to get some water in it; I don't see how it can help it, but maybe I'm missing something.



One thing I might mention in addition.  Check every inch of that riser that doesn't heat.  What you are looking for is partly the obvious -- a sag or low section of pipe where water could be trapped and stay, shutting off the heat -- but also the non-obvious: is there a partial constriction anywhere along that line?  A valve partly closed?  A reducer follwed by an expansion?  An elbow or fitting which might be partly plugged?  Reason I ask is that if there is such a thing, in some situations while you migiht be able to get air by it, you can't get saturated steam such as we use by it.  It will all condense instead.  Just a thought...

CWS

Checked every inch

I checked every inch which was relatively easy. It is all in plain view in the adjacent basement. No valves, all same size pipe so no reducers or concentrics, there are a few spots where there were sags so I drilled holes to let the water out. That helped a little but not much. I could see the steam coming out of the hole I drilled and it was weak... about 6" plum with low volume. That was the thing... I could actually see that it was not making a good head of steam. This was noticed at thej begining of the run. That is why I am leaning towards the fitting coming off the bottom of the main. Is there a way that i can drain this off with a drip leg and if so how would i set it up. I think this may be a good way to test to see if the water is saturated and cooling the steam down at this point. It may be too little too late by trying to run a drip leg at the takeoff due to the steam already colapsing by the time it goes into the run. I thought about running a pipe off the header into the supply? any thoughts?

Rod

System Problems

I agree with you that it would seem reasonable that there is steam being produced since some of the apartments are apparently heating. However seeing the apparent lack of long term maintenance,  I would still run a check on the boiler’s integrity otherwise if it is discovered to be leaking later, it might  look like you had missed it. Besides there would be no sense in suggesting that the boiler near piping needed to be corrected if it the boiler itself needed to be replaced and therefore the piping be redone.



I took another look at your pictures and studied them from several angles. I took the one that showed the piping the best and labeled it. The boiler piping is, to put it mildly, pretty screwy.

Boiler Riser “A” seems to join the header at a Tee with the equalizer connected to the other side of the tee.  With the steam from Riser “A” trying to make its way up the header and colliding with the steam /condensate flow from Riser “B “ and including  the condensate dropping back down the steam riser, this configuration has to result in very wet steam and poor efficiency.



Main Vents- There seems to be 3 returns which I labeled Return “A”,”B” and “C”. Above them appears to be the main vents which I labeled “A and “B” and as there seems to be two Main vents on Return “C” , named them “C1" and  “C2". I can’t  tell from the picture what model these vents are though a couple of them look like they may be Hoffman 75s.



Non movement of steam - Other than a broken mechanical parts like a closed stuck valve,  there are only two basic things that will stop the movement of steam in a system-  Trapped air and/or trapped water. As the main vents on the system would seem to be rather tiny for a system this sized and may not be operating satisfactorily,  I would dramatically increase your main venting by adding at least a one Gorton #2 to each return. (One Gorton #2 has about double the venting capacity of a Hoffman 75) You may find that you might even want to add more venting in the future but at least by renewing the vents at this point you would know the vents are okay.



Trapped water- Jamie had a good suggestion in that you should be able to feel the difference in heat where the water is trapped. The pipe coming off the bottom at a 45 degree is obviously trapping water if it doesn’t have a drip. If you could add a drip at the low point per the drawing from the Burnham Heating Helper, this should do the job. The drip line would have to drop down into a wet return or use a trap.  How many radiators are connected to this pipe?



The “A” dimension is measured from the center of the sight glass (Boiler designed waterline) to the lowest steam carrying pipe. In this case I’m assuming this is at the returns at what I marked as Level “X” in the photo. At a 2 PSI steam pressure this should be a minimum of 28 inches.

The height of the risers/header, per Figure 5.1 on Page 19 in the I&O manual, needs to be a minimum of 24 inches and it would seem you have that okay.



Is the pipe with the trapped water the only line that is causing problems (no heat) ?

Again I would caution you that I’m not a pro so only consider these as suggestions from a limited knowledge amateur.

- Rod