Boiler Cutting out on Pressure

DanS_2

I have an extremely neglected Richardson system that has started cutting out on pressure this season.  I am resetting the presuretrol at least once a day.  I calculated the pressure settings at the beginning of last season using the method in "The Lost Art..."  I had not problems all season.  This year it cuts out all the time.

I have changed nothing physically with the system this year.

Something else curious I have have noticed is that my dry returns are getting almost as hot back by the boiler as my mains.  Don't remember this ever happening before.

Any help or advice would be greatly appreciated

Thanks

jpf321

pictures?

can you post pics and closeup of your pressuretrol and it's settings...this may help.



it sounds like you have may a manual reset pressuretrol perhaps .. and i'm not sure this is what you want for the function you are looking for.



your pressuretrol should cut-out and cut-in automatically as part of the normal heating cycle .. the fact that you say youare resetting it sounds strange.



jpf

DanS_2

Sure Pictures...

I beleive it is manual.  I guess I thought they were supposed to be automatic.

Here are the Pictures.

In Picture DSC_0795 you can see a little lever that you have to push once the mercury switch trips on cut-out.

Jamie Hall

Something's very wrong...

The Richardson system, as you probably know, kept vapour (steam) out of the returns with a dip tube sort of affair in the outlet of the radiators, but allowed air to vent through a small hole in the tube.  Plus graduated valves on the inlets to the radiators, which allowed only as much steam to get in as could be condensed by the radiator.





This combination meant they were absurdly sensitive to pressure!





You description suggests very very strongly to me that steam is getting past at least one radiator into the returns.  Fortunately, you have no traps (except the F&T main vent at the end of each main) to be hammered.  This could cause the pressure rise (steam not being able to get into the radiators and condense).





First, one of those F&Ts may be stuck closed; this would force more air than normal through the radiators, which could break the water seal at the dip tube.  Second, one or more radiators may have a valve which got opened too wide.  This would allow too much steam in, making too much pressure, breaking the water seal, etc.





You shouldn't have to reset the pressuretrol, though -- the worst it should do is cut out and cut in and make a nuisance of itself.  Why do you have to reset it?  Explain, please?  Must admit that I wouldn't use a pressuretrol on a Richardson -- I'd use a vapourstat, set at a maximum of say 8 ounces with a differential of 6.



Edited to add -- ah.  Just saw the pictures.  It looks as though you do have a manual reset pressuretrol.  Tiresome.  Those are normally used only as a backup safety pressuretrol, in case the pressure gets really wonky because the normal pressuretrol or vaporstat fails.  I'd add a vaporstat to the system as above.

DanS_2

More information

I just ran a test to force the pressuretrol to kick off. Here is what happened.

I set the Thermostat to 73 to ensure that the system would run long enough to kick off.

The system ran for a considerable amount of time at about 1.5 oz.  After awhile I noticed that the vents on my mains closed but still the pressure remained the same.  Which is what I expected to see.  Eventually I started noticing that the dry returns were getting hot so I start to feel around to see where it was coming from.  The source was not the wet return but instead a couple of Radiators.

Why would Vapor be escaping the radiator and getting into the dry returns?  Eventually all of both dry returns were hot and the system began to build pressure once it reached about 2.2 pounds the mercury switch tripped on the pressuretrol and the burner shut down.  Gradually the pressure dropped back to nothing but the cut-in did not work and I had to manually reset the pressuretrol with the button/lever on the top as shown in the picture to get the boiler to kick back on.  As you can imagine the Stat was still calling for heat so the burner started burning and the presure was back to about 1.5 onces.

DanS_2

I knew I needed a Vaporstat

One of my next step was to replace the Pressuretrol with a Vaporstat just did not put it as a high priority since when I inherited this mess there was not a stitch of insulation on any of the mains, the basement was 90 and the upstairs was 62 that first year.  You can imagine all of the other issues near boiler piping, venting etc. I will just leave it at that.  You can tell the the installer new nothing about what he was working on by installation of that Presuretrol.  Thanks to this board and "The Lost Art"  I am gaining the confidence to work on this beast myself.

So what would be your recommendation for a Vaporstat?

Jeremy_16

The Pressuretrol in the left picture

is what people are calling automatic. It is set to cut in at .5 PSI. If you take the cover off you can see what the differential is set for to see what the cut-out is. The Pressuretrol in the right picture seems to be a backup in case the one on the left fails. Maybe the back up pressuretrol is set too low and the differential on the left pressuretol is too high.



If the cut in on the pressuretrol in the left picture is .5 PSI and the differential is 1 , the cut-out would be 1.5 PSI. It looks like the backup pressuretrol is set at at about 1 PSI or so. So it would cut the pressure off and need to be manually reset before the other pressuretrol automatically cuts out the pressure.



Could that be? I'm not sure exactly where your pressuretrol should be set, but that is my thought.



Good luck.

-Jeremy

Jamie Hall

That's not so bad, after all!

Actually, it may be running more or less as it should -- bar the pressuretrol, which is the sort, as I said, that is used as a secondary safety cutout (often set at around 5 or 6 psi!) in case the vaporstat doesn't do it's thing.



The chances are very good that the few radiators which are letting steam by may have their valves set a little too open.  Quite possibly, ever since the system was installed.  Nothing's ever quite perfect -- even the esteemed Dead Men!  You might try just closing the valves on the offending radiators just a tad.  Or maybe two tads.  Until another radiator does it... and then quit.  The reason they are letting steam by, most likely, is that they are getting just a bit more steam than they can condense.



Once you get a vaporstat on there, and get it nicely calibrated, what you are going to see -- unless I am badly mistaken (which has happened...) is that the system will run until pretty well all the radiators are nice and hot (after you get done tweaking the few that are ahead of the pack).  Then the vaporstat will start cycling the system to maintain the pressure between 2 and 6 or so, until the thermostat is happy.  And that's just the way it's supposed to work.

jpf321

the grey pressuretrol on the left

as noted above .. make sure the differential on the inside of the grey pressuretrol on the left is set to 1 .. if possible post a picture of that ..



the next thing to check is the pigtail that the grey p-trol is on .. if you say that it worked last year, and doesn't work this year .. my guess is that the pigtail on the grey unit possibly plugged .. and that the system USED to control automatically off the grey unit .. but now with a plugged pigtail .. it is being controlled from the RED/CLEAR unit .. as noted as well above .. the RED/CLEAR unit should be for backup purposes ONLY .. the GREY unit should trip on/off automatically .. the RED/CLEAR unit is there as a saftey in case the grey unit malfunctions (or it's pigtail) .. which is clearly the case you are seeing now .. of course, you may have confused this from the get go and adjusted the RED/CLEAR unit properly and never gave the grey unit a second thought .. it is the grey unit which should be adjusted and the RED unit should be set up around 5psi as a safety backup only ..



yes, a vaporstat should replace the GREY unit and the RED unit should remain as a backup set at 5psi (or so) ..in your mind going forward at a 5psi setting, if the RED one trips, this BIG problem that should raise trouble alarms in your mind.



while you are cleaning the pigtail of the GREY unit .. make sure to ALSO clean the pigtail of the RED unit. they should always be cleaned together.



i hope this make sense ..

DanS_2

Good Info

I was totally confused.  And here I was blaming the installer.  I never opened the grey box, I that that that was the cut in and the red was the differential.  All this time I thought they were working as a unit.  This explains a lot. 

I opened the grey box and the differential is set to 1 and the cut in is set to .5 which is more than I need but it is the lowest they go.  I would have to agree that the grey is not functioning any more since the max this thing should run before the burner cuts down is 1.5 pounds and it cut out about 2.5 during my test last night.

I looks like I may need to go ahead and get that Vaporstat now to replace that grey Pressuretrol.  Any recommendation on a model I should buy?

Paul Fredricks_3

vaporstat

The Honeywell L408J 1009 is the one you want. The gray one (PA404) will work, but the Vaporstat is better. I think you could set it 8 oz cut out with a 6 oz differential.



The other pressuretrol should be set up to 5 PSI to act as a safety back up, just in case. As mentioned above, take the controls off and make sure the pig tails are clear.



The way the radiators were supposed to work: If you look at the valve on each radiator it should have a pin that stops the handle from opening any farther. The pin was set up to only allow in about 80% of what the radiator could handle steam-wise. Those handles get pretty loose and can easily go past these settings. If the valve is still working properly on the inside, close it all the way, then open it to the pin. That should give you the right adjustment.

Paul Fredricks_3

And

Speaking of Richardson systems, I revented one last year that was way under vented. I see that their consistant 1.99 K-factor went to 2.5+ for the last few deliveries. That equals a 25% fuel savings? Am I figuring that correctly?

Jamie Hall

Amazing

what a simple tune up and venting can do, isn't it?

jpf321

keep in mind

while you are at it .. you may want to get a low pressure guage .. such as this ..

http://www.gaugestore.com/prodinfo.asp?number=33015 0-20oz/si

or this

http://www.gaugestore.com/prodinfo.asp?number=33020 0-3p/si



i run the 0-20oz gauge...i like it b/c it also has inches of water scale

Timco

Bass player?

Can we really trust advise from a bass player???



Tim