It has been awhile since I have dealt with Steam boilers and need some help with pressuretrol settings.
working on a 72 year old steam boiler in a 3 floor apartment building with 8 to 10 apartments. One radiator in each apartment, radiators are 2 pipe. I have no specs on this unit, no plate, nothing. Long story short, another hvac company was out and never returned. Pressuretrol is wired in series with all the controls (stat, fill valve, water level valve and pilot saftey) wired in normally closed like a limit. The pressuretrol was set all the way down and I am unsure where to set main and differential.
After messing around with it I was able to get solid steam at about 3.5 psi. I am not sure of this, I belive most residential steam are set for 2psi. On the differential setting would you want the pressure back down to 0 psi???
Any help would be appreciated