Pressuretrol and Pressure Gauge

stevenyc

Well I'm going to put additional main vents in this week and I've installed the visionpro 8000 stat. Things are looking better but a few things that I am still curious about are the pressuretrol and boiler steam gauge.

The pressuretrol is made by Honeywell and that may be a redundant explanation if that is a Honeywell name brand. Anyway, I have the pressuretrol set very low, below the markings on the right side for max PSI and I have the differential set to almost 2 on the left side.

The pressure gauge usually sits at the 0 mark when idle and curiously it only has 4 markings up to 5 PSI...meaning that each mark is either 1.25 PSI or am I completely missing something obvious here. When I fire the boiler, the gauge reads 0 for about 30 minutes and then begins to rise. The boiler builds steam up to almost the third hash mark, even though my pressuretrol is set to what should be a pressure below 0, and then shuts off???

I suspect that BOTH the steam gauge and pressuretrol are off. If this is indeed the case, how do I go about testing whether this is in fact the case. I know that my boiler short cycles after heating up and cuts out because of steam pressure before satisfying the thermostat but I'm hoping that venting the mains will alleviate that.

I'm hoping to achieve some level of accuracy with the steam pressure gauge and pressuretrol so that I can depend on it. In other words, what you see is what you get. From searching previous posts it appears that most people don't have a lot of trust in the steam gauge on the boiler. Perhaps, my hope is only a dream. I would appreciate any help with this. Thanks!

Unknown

Where is the gauge located ?

Like many , I used to install the gauge directly into the boiler . But seeing what happens to the gauge after a year in service , I now install it after the pigtail to give it some protection . The easiest way to check is to buy a new gauge that can be quick connected to one of the boiler's drains . Or you can just add another gauge that reads in lower increments . You still need to keep the original one there or a newer one that reads double the steam relief valve psi rating - for code reasons .

Gary_17

pressuretrol

It sounds like the pressuretrol is functioning properly. There are a couple of different types, but the most common one the differential is added to the pressure setting making that your cut-out pressure. If the setting is at it's lowest it's @ 0.5psi + 2 diff.= @2.5psi. So it seems the gauge may not be too far off.