PSI

Brooklyn1

I have a 4 story townhouse with boiler in the cellar (below the 4 floors). My boiler seems to maintain around 7 PSI when on, which I've read is higher than it needs to be. On the other hand, system seems to be happy, heating the house well, and my heating bills aren't bad. Do I need to try to bring this down for safety or other reasons, or is it OK as is? If I try to adjust, I think the Honeywell on the left is the high-limit control and the grey box on right is the operating control. Any suggetions for proper settings? Thanks.

nicholas bonham-carter

high pressure townhouse

no matter how well you think your boiler is working now, it will burn less fuel maintaining 1.5 psi, than with 7 psi.

the pressure may have been raised up to compensate for inadequate main [not radiator] venting,which also enriches the fuel company.

enter the model number for the pressuretrol into a search here, and you will see the setting instructions.

if you really want to save money, you could get a vaporstat/low pressure gauge, and lower the pressure to 8 ounces.--nbc

Jamie Hall

Not sure which one

is the principle control on your system -- I can't see the photo well enough.  In any event, NBC is right; the primary control should be set to cut out around 1.5 to 2 psi (if this is a conventional one pipe or two pipe system) and cut back in about 1 psi lower.  The secondary control will be set higher, and serves as a backup if, for some reason, the primary control doesn't do its thing.  You might send model numbers or close up photos of both controls.



No, it isn't a safety thing; even twice what you are running isn't a safety issue.  It is a money issue.  Once the pressure gets over about 1.5 psi, the additional boiler run time to bring the pressure higher just squeezes the steam that's in there, and doesn't add any extra heat to the building to speak of.  No point in burning fuel you don't have to!



Venting also helps.  What you want to look for is on the steam mains, towards their ends, their should be some big vents -- main vents.  If they aren't there, or are too small, it may be that the radiator vents are having to do all the work, which makes it very hard to balance the system and, again, makes it have to run longer to get the same heat.  Take a look and let us know what you find!

Brooklyn2

PSI

Thanks for the replies.  I do have two main vents.  One is a Hoffman 75 and the other is a Gorton (couldn't read the number).  The Hoffman is spurting and bubbling, so it's probably time to clean it, or perhaps replace it with something better??  Boiler is a Weil McLain EG 55.  A photo of the primary contol is attached.  I moved it down to 1 cut in and 3 cut out and can probably take it lower.

Jamie Hall

What is the model number

of the other control -- the one with the transparent cover?  And what is it set at?

Brooklyn2

I'll have to

get back to you on that tonight.  I was looking quickly this morning and didn't see a model number.  I moved it down to 7 from 15.

Brooklyn2

Found it

Here's the info on the secondary control. Thanks

Paul48

UhOh

No LWCO?

Jamie Hall

So far as pressure is concerned...

you should be able to set one of those two controls to 2 psi cutout and 1 psi cutin.  That should be a good place to start.  I'd set the other one to about 5 psi, to serve as a safety backup.



If the one doesn't seem to hold the pressure properly, the pigtail to it may be clogged.  They do.  Fortunately, it's no big deal to take it apart (turn the boiler off first!) and clean it.



But see what happens just setting them...