Heating Help

need a steam pressure cycle switch

I need to replace my steam boiler pressure switch.  I have read on this board from a few different threads for a two floor home I should set the switch to .5 psi and the differential to 1 psi.  The problem is my boiler keeps going up past those settings to 4 psig and then shuts down.  I have changed the gauge with a brand new one to make sure it was not a faulty reading but the gauges are correct.  The current pressure switch is a Honeywell but I would like to know if there is something better on the market.  A friend of mine bought a brand new Honeywell switch and it was not operating at the correct pressures he set it to. Is there anything better out there?

Not just the switch.

Did you clean the pigtail?

Clean

Yes,. The pigtail is clean.

pressuretrol location

some pressuretrols which are tapped into the top of the LWCO can can plug up below the pigtail--could this be the location, and problem with your pressuretrol?
unfortunately, the selection of pressure controls available is limited to the products of only one manufacturer--honeywell. if you decide to replace your pressure control, get a vaporstat [0-16 ounce]. as you continue trying to make your system more comfortable, and quiet, and economical; you will eventually realize that you need one--so why not now?--nbc

Thank You which one do I need?

I was looking at the vaporstat's and there are two with the 0-16oz. 
L408J1025 SPST make on pressure rise Only
or
L408J1009 SPDT make R-W, break R-B on pressure rise

another question

I would also like to know why I would not get the 0-4 psi moodels.  I noticed the 0-16oz and 0-4psi both are used with a 0-4psi system but have different operating ranges.  I am onfused could someone explain please.

Bump for an answer please

Could someone please answer my questions please so I can order the correct vaporstat. Thank you.

0-16oz "1009" Break R-B on Rise

i hadn't seen this thread .. but I think most people here would recommend 0-16oz "1009" Break R-B on Rise