Boiler never reaches cut-out pressure

BroMariano

We have a one year old Smith Boiler in an old school where we run a Youth Center, Medical Clinic, and Homeless Shelter. The building has 3 floors and a basement.



Recently, the boiler has been running for a few hours at a time and never reaches cut-out pressure. The gauge stays at 0 PSI. We have tested the gauge and the Pressuretrols, and they are working fine. The boiler only shuts off when the thermostat timer stops calling for heat. Currently, the Cut-In is at 0.5 PSI with a differential of 1. The other pressuretrol is set to 5 PSI.



Some radiators only heat halfway, and very slowly. Others stay cold all the time. When we remove the vents, air escapes very slowly, and the cold radiator begins to heat, but only by the valve.



Most of the pipes just below the radiator shut-off valves are very hot, but there is not enough pressure to force the air out and heat the radiators. We have searched for steam leaks and cannot find any.



Any suggestions for troubleshooting the location of the problem?

Charlie from wmass

We need more info

What smith boiler do you have? any idea of the connected load?

jpf321

a few thoughts ...

what is the connected EDR load? what is the model of the boiler?



lacking adequate pipe insulation? are your pipes acting like rads and emitting heat before it gets to the rads?



send pics of your boilers including near boiler piping from several angles.



did the system work prior to the new boiler?



was the difference in waterline if there was any attended to? do you have any wet returns that are now dry with steam crossover? or the opposite case, do you have water stacking into your steam mains?



do you have adequate/capacious venting on the mains?



since you say you have vents...I assume 1-pipe system.



you may also want to run down the "radiator troubleshoot list" here: http://www.heatinghelp.com/forum-thread/129206/Radiator-not-getting-any-heat#p1185051

BroMariano

More Info

The Boiler is a Smith 19A



Load is 1.1 - 1.3 million Btus



Also forgot to mention there is no thermostat. It is on a timer that heats the building at certain times of the day. When the timer is on, the boiler runs continuously. We've been setting it to run longer because of the lack of heat.

Charlie from wmass

Is that heat loss or E.D.R. ?

Which 19 A? They come in several sizes. Did it work last year?

jpf321

which one?

there are several 19As in the line .. which one do you have .. so you are saying that you have about 1.2MMBtus (5000sq ft) of connected EDR? so maybe you have the 19A-11 or -12

BroMariano

Response to "A Few Thoughts"

I will be able to get a camera tomorrow to post pics. (I am a Franciscan in the Bronx, and will have to borrow one.)



And my apologies for leaving out a critical detail, yes, one-pipe system.



+ The Pipes are well insulated in the boiler room, as far as we can get to the risers.

+ The system worked with the old boiler, and even ran well last season with the new boiler.

+ The water level and piping is the same. We have one wet return and one dry return with an F&T trap, same as last boiler.

+ There is NOT adequate venting on the mains. However, we attempted to replace a vent at the end of the wet return with a manifold of 3 3/4" straight vents with no difference.



I ran through the list from that forum prior to posting.

#4 is becoming a concern to me

("is it connected to a horizontal pipe which my be improperly pitched and/or holding a pool of water.")



Can someone please explain how to approach #5?

("are your rads/mains all balanced as a "system whole" to begin with? then you can tweak each one from there?")



Also not sure of #9. Some of the radiators spit on occasion.

("are you producing "dry steam"?")

BroMariano

Boiler Type Smith 19A-8

Boiler is Smith 19A-8

arches

low/high fire

If you have an 11 or 12 section, you probably have the Carlin 801 burner. That model has a low/high/low burner feature. There's a switch located on the burner which forces the burner into low-fire only mode...is it possible that switch has been thrown? 

Listen to the burner at startup and see if it goes into a louder mode 15 seconds or so after startup. That's the high fire.

Charlie from wmass

what is the fuel of choice?

Is this an oil, gas, or both? Not all 3/4" vents are equal.

BroMariano

Low Fire/High Fire

The burner does in fact have a low fire / high fire switch. We have tried both settings. It has been set to High fire with no noticeable change in heat or pressure.

BroMariano

Fuel is Gas

Boiler is fired by Natural Gas.

arches

oh, an 8 section....

seems thats a Carlin 702 burner...single stage. guess its not a low/high fire issue.

jpf321

checklist

for #5 .. you need to obtain the books here .. or have me come and visit sometime .. i'm NOT A PRO .. but I'm enthusiastic! .. http://www.heatinghelp.com/forum-thread/129085/Uneven-Heating#p1184396



for the main venting .. what type of 3/4" vents did you add .. are they copper in color or silver? round like a clock or pointy like a bullet?



#9 .. dry steam is actually a technical term as Dan pointed out the other day .. basically the steam in the system is invisible and not carrying water vapor .... if you look at the outlet of a teakettle .. the first inch is invisible, dry steam,  .. after that inch you can see the steam as it condenses in the air and water you are seeing is the water vapor.



if you indeed have a connected radiation EDR (equivalent direct radiation) load of 5000sq ft .. the boiler is too small .. however, that does not explain why it worked last year ..



the only other thing I can think of, but ruled out earlier b/c you stated the boiler was new .. is an internal leak in the boiler .. have a look at the chimney tomorrow and see if you see large plumes of white billowy "smoke" rising above. this would not be a good sign.

jpf321

i responded above

scroll up in case yoou missed it.

Charlie from wmass

19 A 8 section is rated

Lower than your rated load.

BroMariano

Response to 'checklist'

3/4" vents are silver and bullet shaped. Harp/USA # 59.



As far as the internal leak, there is a shut-off before the header. To test for a main leak, we shut off that valve so the steam condensate flowed back into the loop and no steam went through the building. The boiler reached pressure in less than 3 minutes, and cycled just fine.

jpf321

very good info

that's a relief huh. glad to hear it. 

BroMariano

Regarding Rated Load

The old boiler used to run this same building, plus a church and two convents, so it was super huge. Later, the church and convents were removed from the system, but the boiler remained. When the boiler died, they wanted to install the same size, not realizing that it used to heat a much higher load.



At the time of the new installation, they calculated the load for the building according to Dan's books, and chose a boiler a little larger.



Maybe I should have someone review the load requirements?

Charlie from wmass

I am thinking you need to let it run for a very longer time

Since it is below the rated load you need to keep from having a large set back especially in this cold weather. I think it is simply too small. One thing to check would be to clock the meter. The boiler may be firing but it may not be getting the rated input it requires. Can you access the gas meter and are there other gas appliances on the gas line? If you can isolate it so only the boiler is running and you can clock the meter you can then figure if the boiler is getting the required gas.

jpf321

cold church now huh

that's one way to keep the parishoners awake ;-)



a review of the load would be useful .. but if they did it correctly the first time, and it worked last year .. it seems to point to something else ..



when were the main vents (which I can't find online) installed?

jpf321

i'm happy to swing by ...

if you indeed want to review the load req's .. i am happy to swing by and measure it up with you, for charity. i've got the EDR book and the Gill/Pajek paper .. contact me directly if you like ..



i see that Charlie is thinking burner problem .. charlie is highly respected  .. follow his advice... i don't play with fire just water ;-)

Charlie from wmass

I think they went by input not output?

If your load is 1.3 million BTU then you would need a Smith G19 S A 10 boiler. If you had warmer weather with the Radiators not working so hard then you could get steam around. You may need to install Thermostatic valves in sections that are receiving heat. As they warm they will close and allow the heat to travel further, Shedding load as rooms warm. On a system of this size you could see a considerable savings on fuel. But with the undersized boiler you will probably gain comfort not save fuel.

BroMariano

Main Vents

I'll have to ask the older friars if they know about the installations. We were only able to find a single vent near the boiler, which was on the last elbow of the return before dropping below the water line. That elbow is at the ceiling, about 10 feet above the boiler.



I checked above the drop ceilings in the basement. I was not able to find any vents on the mains before the returns.



On another note: I was just told the installers put a chemical in the boiler and ran it through the whole system at installation. The result was incredibly dirty water and some leaking radiator valves. I wonder if it gunked up some of the horizontal piping since last season? When we remove the vents, there is very weak 'panting' as described in the Systems troubleshooting section.

BroMariano

EDR Review

Charlie,



I will give the gas meter a try.



Most of the radiators have thermostatic vents on them already. But even the radiators close to the boiler are not heating properly. I haven't found a single radiator that is heating fully, or even one that is heating more than halfway.



If I close the valves on all the radiators and open them a floor at a time, will that be any indication?

BroMariano

Calculating EDR for Charity

Thank you for the offer. I will speak to the friars in charge of the building tomorrow to see how they want to proceed. I think I have some information to go on at the moment, but I'm sure they would love to have someone else come out and take a look.



We are not far from Yankee Stadium, 155 and Melrose.

jpf321

charlie has a simpler

explanation although bad news .. perhaps they read column 10 GASMBH of the above chart instead of column 7 Steam MBH. .. he also has a possible solution .. shutting down rooms as they heat using TRVs .. and thereby shifting/shedding load..



i was just wondering if the vents were installed recently in order to assist with the problem

BroMariano

Will return tomorrow with photos

I have to leave the office now. As we do not have internet in our friaries, I will return to post the photos tomorrow. Thank you all for your assistance. Your time is greatly appreciated!



I am going to search for Main Vents, review the EDR calculations, and check the gas meter.



I'll post our progress as soon as I can. Thank you again, and God Bless!

BroMariano

TRVs were always there

The TRVs were installed with the last oversized boiler. I am really paying attention to your thoughts about the EDR. I think this may be where we have to begin.

jpf321

looking forward

looking forward to your updates .. gnight. 

nicholas bonham-carter

cold radiators

can you jumper the boiler, to simulate a "call to heat"? if so, then let it run, until you feel the heat rise into the radiators, and see if they have "steam arrival" at the same time.

i suspect that there is a problem with the air not being able to get out quickly, in front of the steam. can you tell us what sort of vents there on the main lines [not rads].

that possible venting problem could be compounded with the method of control for the boiler. a timer must surely have problems sensing the need for heat, and can  only turn on and off the system in a rather simplistic fashion. there are other controls out there, the simplest of which is a good thermostat, placed in the coldest area of the building, so it can sense the dropping temperatures.

first of all, the system should be made to function properly as far as getting the steam to all radiators as quickly as it once did, when the system was first installed.

i can't remeber if you said that you had the steam books available from the shop here. if not, they are most informative.

if brother martin is still with you, please give him fond regards from nicholas and jane from omaha...nbc

Charlie from wmass

Glad to hear you have TRV's

Perhaps with some pictures and an idea on the venting we can help you out further. If you can get the EDR double checked that would be good. The other question now is are the TRV's opening properly? Trying to see what has changed since last year. It may be a venting issue after all.

jpf321

sure thing ..

... besides folks say i should get out in the field more :-o

http://www.heatinghelp.com/forum-thread/129197/main-venting-doesnt-matter#p1185014

Charlie from wmass

You should be able to accomplish this with the TRV's

turn them down low and start with the farther radiators and open them up. See if you are getting flow through the TRV's. I would leave the radiator valves be. Are the TRV's in place of the steam vents? I am asking as I have seen two pie or even hot water TRV's used on one pipe steam systems.

jpf321

TRV article

here's a great article on TRVs .. this is focused on 2-pipe .. but may give you more things to think about .. in one pipe you need the TRV to be in the "vent" location as charlie suggests .. and it needs to have a "vacuum" breaker .. they make special TRVs for one-pipe. and more importantly, it needs to be installed in a proper way .. which is mainly what the article addresses.

http://sites.google.com/a/energysavingscience.com/www2/BSETRVs.pdf

BroMax

Pics of Boiler

Sorry, could not login. Using another name. This is still BroMariano.



Here are the pics of the installation:

(1) Boiler

(2) Boiler Piping

(3) Header



More pics coming...

BroMax

More Pics of Boiler

(1) and (2) are pictures of the returns.



(3) is the water level above the returns. I have made sure that the water level has not affected the A-Dimension as well.

BroMax

Vent Pics

These are the only vents I could find.

(1) This is the end of the first Main. From here it drops down 5 feet, Then drops another 5 feet to ground level, then 3 feet into the pit. There is a bucket vent on the end.

(2) This is a Gorton #1 that is on a 5' vertical pipe that is connected to the elbow before returning to the boiler room. (See photo 3).

(3) The lowest elbow shown here returns to the boiler room, drops 5 feet to floor, then another run across the floor, then an elbow, and finally a 3 foot drop into pit.

(4) Photo of removed pipe with Gorton #1 on top.



It appears the Gorton #1 was used to supplement the bucket valve, as it is dang hard to get into that space.

BroMax

Final Vent Pic

This is the last bend of the second return before dropping to the floor. That elbow had a Maid-o-Mist vent on a 12" vertical pipe. The vent was blowing a lot of steam. Replacing the vent with a manifold of 3 3/4" vents as mentioned above produced the same result.

BroMax

Our Thoughts...

So based on the suggestions we received last night, we are going to spend the day doing the following.



1. Remove and replace the bucket vent with a new Gorton #1 or #2 at the end of main 1.

2. Remove the 5' vertical pipe from the end of the elbow on return 1.

3. Replace the vent at the elbow of return 2 with another new Gorton.

Jamie Hall

Sort of lurking on this thread, but paying attention

Looking at your pictures and reading throught the rest of the thread, it seems to me that you have, unhappily, two problems.  First, boiler size or no, more venting on the mains will help.  They are not hard to install in clusters (look up "menorah" on here, for example) and, if the pipe tapping is big enough where the existing vents are, you can add a lot.  There may be a few other places where they can be added, too.



Unfortunately, that does not address the problem of boiler size.  There I am very much in agreement with Charlie -- that boiler, if the rest of the numbers are right, simply isn't big enough.  If you can find a steam pro. (there are several in the general New York area) to come and double check the numbers, it might be a good idea.  Problem is, a too small boiler doesn't just give less heat; it may give no heat at all in parts of the system.  What happens is that what steam it can create gets condensed before it has a chance to spread throughout the system.  Perhaps the best way to handle it is, as Charlie suggested, to use the TRVs to essentially sectionalize the system.  Bring part of the building up to where those TRVs start to close, and then start another part of the building, and so on.  Sort of a nuisance, and hardly automatic, but it may work.  The biggest problem would come from trying to recover from a deep setback: if the room temperatures were all below all the TRVs, they would all be open at once -- and it is quite possible that the system might not be able to recover at all.  So I would avoid big setbacks!  Or, since you are running off a timer, might it be possible to run the boiler more often, for shorter times, to maintain more even temperatures throughout the day and night?