Burnham Gas Boiler - Blown Varivalve

bertscara

Hello everyone...

I have a burnham gas fired steam boiler, model# sin5lni-le2. Had it serviced this past week where they drained it and remounted the pressure trole (guessing they checked the pigtail).

Since then I've blown the top off a varivalve on the second floor. I noticed that the boiler pressure is higher in the morning / when the house is at about 64 deg and the thermostat is set to 70 deg. Max pressure seen before I shut the boiler down is 6 psi. At the time I'm guessing the pressure trole, which is set to shut the boiler down at just over 2 psi, is not working or the pressure gauge is bad.

They've been back since then and replaced the pressure trole. They were there for about an hour in the middle of the day and the pressure never seemed to exceed about 1.5 psi, so I'm guessing the pressure gauge is not bad...? House temp was already at 70 deg and the thermostat was set to 75 deg to allow the boiler to run.

Note that all the radiators are getting hot in both cases. Hissing is very loud in the morning so it does seem that the boiler pressure is in fact higher.

Any ideas?

Jamie Hall

A long recovery like that (most of us might be inclined to say that your setback is much too much) will cause the boiler and system to operate at maximum output -- and it will cycle on the pressuretrol. That said, 6 psi is way too much pressure. Either the pressuretrol isn't working or the pigtail and connection into the boiler is clogged -- or someone wired it incorrectly.

bertscara

Thanks for the feedback. I watch the second time they came. They removed the pigtail when replacing the pressure trole and physically cleared it out as well as the line the pigtail is connected to. Both seemed to be clear / not much to clear out.

Also... two different techs wired the pressure tole. Once when initially removed for cleaning and once when they replaced it. Not much to wire... Hoping they're competent enough as they work for a very reputable company.

Can you tell me what you mean by "setback"?

Jamie Hall

Setback is the term used for the practice of running a lower temperature in a space at night or when it is not occupied vs. daytime or when it is occupied. And, specifically, the amount the heating is turned down (or the air conditioning turned up). Thus in your initial post, one would say that you are running a setback of 6 degrees (64 to 70).

The easy assumption is that a setback will save energy. Whether it actually does or not, however, depends on the type of heating system and the nature of the room, since it takes time -- and a considerable amount of energy -- to heat a space back up (in your case, from 64 to 70). Forced air systems seem to tolerate fairly large setbacks, mostly because they don't really heat the space, just the air in the space. At the other extreme radiant floors may take hours or even days to change the temperature of a space -- and won't tolerate any setback at all.

One can get into quite lively debates about whether setbacks save energy or not...

bertscara

Ok.. looked up the meaning of setback and you're saying that the difference in temperature between night and day settings is too great making the burner run "Balls Out" an old steam engine term ... until the house comes up to heat.

Couple things... The Pressure trole is set to shut the boiler down at just over 2 psi, but as I said before not shutting the system down even at 6 psi even though they just installed a new one. I also read that the flame should kick back until the pressure falls within normal operating pressure... not sure if this is true in all cases / boiler makes and models.

One thing I did notice is the technicians both set the water level much higher before I had the boiler serviced / before the issue. I also read that too much water in the boiler would cause it to run at higher temperatures. Anyone know if this is true?

Thanks again for anyone's help.

neilc

new ptrol could be bad out of the box,
or they wired it wrongly,
or the pigtail is not clear all the way to boiler pressure,
( I know you said they checked / cleaned)
post a picture of the ptrol, pigtail,
and how good are you at following wires?

BobC

Sometimes you get a flap of crud inside the boiler at the tapping in the block where the pressuretrol threads in. This flap of crud will allow pressure to come out but not come into the pressuretrol so it can't "see" what the boiler is doing.

Take some pictures so we can see how the pressuretrol connects to the boiler, sand back enough so we can see anything near that pressuretrol.

Bob

bertscara

neilc

so as others have said,
Ptrols can be poorly calibrated,
If you watch the boiler (thermostat pushed up high so it keeps running) while it fires, it gets up to 6? and shuts off?
what pressure does it start back up at?
It looks like you have room to dial the front scale down from what looks like 1, to the bottom,
caution, if the screw adjustment starts to resist you have reached the lower limit.
inside the cover, what is the white wheel(differential) set ? should be 1 facing forward to you.
picture of the inside of the Ptrol

bertscara

That's one of the issues.... it doesn't shut off. I shut it off once it reached 6. The other question is why is it getting to 6 psi?


Some Ptrol pics attached.

Gordo

That P'trol looks like it is set too high. The "cut-in" setting should be bottomed out.
Also, it is recommended to use a brass pigtail rather than steel, which can rust shut.

bertscara

Thanks... I thought so but the company that performed the service is sending a supervisor on Wednesday and I want them to see how they left it. After that I plan to change out the pigtail for a brass (been seeing that on many different posts) one as well as T it off and add a low pressure gauge parallel to the ptrol to it's seeing pressure. It'll allow me to see the operating temperature better which is tough to do on the 30 psi gauge when the operating pressure of the system should be about 1.5 psi.

Thanks again everyone for your help. I'll let you know how it turns out.

bertscara

Update as of 11/3/2021... The company that serviced the boiler came back to trouble shoot the pressure issue. They were able to recreated the issue seeing more than 5 psi on the original Burnham pressure gauge and the boiler did not shut down. They replaced the p'trol (brand new out of the box... The one they installed previously was used) and added a second 30 psi pressure gauge (brand new out of the box) inline with the p'trol (Pics attached). We ran the boiler and the old gauge, after sitting at aout 1 to 1.5 psi for some time, started to rise as before up to about 5 psi. At the same time, the new gauge barely moved maybe 1 psi. Their feeling was that the Burnham gauge is not working properly, possibly out of calibration. They feel that the problem is solved and that I'm good to go.

I'm ordering a new Burnahm gauge today to replace the old one just to confirm.

Any thoughts? Does anyone disagree with their conclusion?

neilc

i'll go,
turn the boiler off at the service disconnect switch,
disconnect 1 wire at the Ptrol, and tape it safe so it doesn't ground or short,
set the thermostat all the way up,
turn the boiler back on at the service switch,
if the boiler fires, something is miswired,
and that needs correcting.

having the 2nd gage isn't bad, but,
someone's NOT paying attention and getting to the root of your problem

bertscara

Can anyone explain why the gauge onthe burner is getting to 5 psi when the gauge on the p'trol barely gets to 1 psi?  I'm mostly worried that the p'trol isn't seeing the right pressure and not shutting the boiler down.

neilc

bertscara said:

Can anyone explain why the gauge onthe burner is getting to 5 psi when the gauge on the p'trol barely gets to 1 psi?  I'm mostly worried that the p'trol isn't seeing the right pressure and not shutting the boiler down.

I think you're correct that the p'trol isn't seeing the right pressure.
I had the gages mixed up when I suggested the wiring being wrong,
and now you need to check the pigtail,

either remove the Ptrol or pull the gage(which would be easier)
(this will get a little funky,)
with your mouth, or a snug fitting hose, and your mouth,
Blow into the open hole, if the pigtail is clear, you'll blow a little water back into the boiler, and blow easier then,
but since the pigtail or boiler port seems clogged, you won't be able to blow thru,

so, now you have to pull the Ptrol, and then unscrew the pigtail from the boiler,
send your screwdriver thru the boiler hole the pigtail was in,
send it in a couple inches to be sure that port is open,
now pick, prod, and open that pigtail so whence it's cleared, you can blow thru it, easily,
or replace the old pigtail with that new copper one.

once the pigtail is back on the boiler, add a little water to the loop to prime it,
reconnect the Ptrol and 2nd gage,

the pigtail or boiler port is clogged.

bertscara

Pigtail and boiler port are clear. Checked and found to be clear twice in the past week....

I beleive the p'trol is working. The Tech tripped it to make sure.

I will say that when the boiler is idle for a while (about an hour or so) the Burnham gauge sits at about 1.5 PSI while the second gauge in line with the p'trol sits at dead zero. Again, to the technicians (the one that installed the new p'trol and 2nd gauge) point the burnham gauge on the boiler may be bad and/or out of calibration.

Ordered a replacement Burnham guage and another pigtail to mount the burnham gauge to the boiler (if this makes sense?). I'll let you know what I see.

mattmia2

So do you have a bad air vent and gauge and since they just swapped parts instead of troubleshooting they failed to find it?

neilc

well I'm running out of "changed my minds",

the indicator on the Ptrol is up, just under the 2,
dial it down to the bottom, don't force it,
just counterclockwise till it starts to resist,

worse the happens is the boiler does not restart,
and then just dial a turn clockwise till it gets responsive,

actually, there is worse yet,
you could unscrew too far, and have loose parts inside that you would need to reattach,
just counterclockwise till the adjustment starts to resist.

the 2, and the possible sloppy differential, could be getting you up above 5 on the gage(s),
you never said what it cuts in at,
but I'm thinking that's because it's not cutting out either, correct?

bertscara

When you say a bad air vent do you mean the Main vent or a radiator vent valve?

I checked the boiler this morning as the house was coming up to heat. Again running up to about 4 1/2 psi on the boiler gauge and about 4 on the pigtail gauge but it did cut out. I adjusted the p'trol down to the 0.5 psi mark and the boiler cut out at about 3 on the boiler gauge and 2 1/2 psi on the pigtail gauge. It does seem to be working but still don't understand why I'm seeing a 1/2 psi difference between the two gauges. Both are brand new out of the box but we all know that doesn't always mean they're working properly.

Based on the above it seems that the gaugues I replaced were wroking properly. Oh well... I'm out a few bucks but am happy to be learning...

The p'trol adjustment is not easy to do due to lack of markings between 2 and 0.5 psi, but I'll check it again tomorrow morning when the house is coming up to heat again.

Hopefully things will be working properly tomorrow morning and I can come back, report out, and close on this thread.

neilc

don't worry about a 1/2# between two 0 - 30 gages, you're in a ball park, (even new, out of the boxes)
consider replacing the gage at the pigtail with a 0 - 10, or 0 - 5 when you get the pressure below3 consistantly.

and don't worry about the lack of markings on the Ptrol scale, they're not that accurate either,
that's why you just gently bottom the scale out, and tweak it back up if the boiler doesn't refire,
you're trying to stay below 2, or 1 1/2, or as low as you can,

bertscara

Just wanted to post this as it's the best description and explanation I've seen... pass it along...

https://www.peerlessboilers.com/wp-content/uploads/2018/01/OnePipeSteam.pdf

bertscara

A lot of good feedback neilc... thanks!

I've attached a few new pics...

Note that the gauge on the pigtail is now a 0-5 psi gauge.

I adjust the p'trol as you explained and am able to get the boiler to cut out between 2.25 and 2.75 psi depending on which gauge I'm reading (again the difference between the gauges... burnahm gauge reading about 2.75 and the gauge on the pigtail reading 2.25 psi).

The boiler is cutting back in at about 0.5 psi as per the gauge on the pigtail. The brand new out of the box burnahm gauge is sticky that low, even when tapping it, so don't trust what I'm seeing.

I tried to get the boiler to cut out at about 2 psi but when dialing back the p'trol i'm not feeling any resistance on the screw about 1/2 turn once hitting the 0.5 psi mark so am worried that I'll back the screw out completely as per your earlier comment.

Any additional thoughts. Is the system safe in terms of damaging anything (ex. vent valves, fittings, etc...) or not as efficient at this cutout pressure?

KC_Jones

If it’s getting to those pressures, and your main venting and radiator venting is proper, then that’s probably about as good as you can get, unless you want to switch to a vaporstat.  Cutting out lower will cycle it more frequently, but the pressure won’t be as high overall.

If you ever replace the boiler, make sure it’s properly sized to avoid this.  I’d speculate it’s currently fairly oversized based on the pressures you are getting.

neilc

you need the 0 - 30 for others,
you have the 0 - 5 to look at,
ignore the 0 - 30 unless the 5 gets pinned,
but you're not going there.

the cut in at 0.5 is good,

cut out at 2.5ish, makes me wonder if there is room to dial the differential wheel lower past the 1,
(remember I said "not that accurate" )
the differential wheel will hit a firm stop, be brave,

that picture with the new gage at 3.75, this was before you dialed the Ptrol lower, correct?

how are you for main venting ?

bertscara

The pics of the gauges are before adjustment... You're correct. 

I'll take a shot at dialing back the differential dial below 1.

The main vent is located as per recommended design based on what I've seen, but short of recommended dimensions.  I'll take a picture and add actual dimensions.

Thanks for all the help!  Greatly appreciated!

bertscara

Good morning All...

Followed neilc's direction and the best I can get is about 2.25 psi cut out and cut in at about 0.5 psi.

I also attached a pic of the main vent and the condensate lines acoming back to the boiler. I beleive there are two...

The black one with a main vent at the point where it turms down but I beleive the greenish line is a second condensate line? seeing as it ties back in to the condensate line back to the boiler as per the pic.

There's now way I can add a vent to the second line where it turns down in the ceiling. Can I add a vent where it turns down just before tying into the main condensate line back to the boiler? Would this help the overall operation of the system?

FYI... went to a freinds house in town who also has a one pipe Burnham Steam system. He has two condensate lines running back to the boiler. He has vents where both lines turn down.

That said... all radiators are getting hot relatively quickly... no issues there.

bertscara

neilc

bertscara said:

Good morning All...

That said... all radiators are getting hot relatively quickly... no issues there.

maybe it's time for a beer,

it looks like you're thinking of venting down low by the floor, or under the water line of the boiler,
that will Not work, vents don't work under water,
and returns, wet returns, are full to the water level of the boiler, or higher as boiler pressure pushes water up and out into the system,

but, if all radiators are getting hot relatively quickly...
and you're not having balancing issues, rooms hotter or colder that others,

well, beer.

jhewings

I think your location is below the water line? So no to a vent there.

jhewings

What is above the suspended ceiling where the main turns down?

bertscara

Ahh yes..  absolutely below the water line of the boiler...  duh.   

The rooms are heating well and well balanced. 

The 2nd pipe is butted up against the joist and floor.  If everything continues to work well don't think I want to go through the hassle of adding the second vent.

I think you're right..  time for a beer!

Thanks again everyone!!!