How do I know the correct settings for my vaporstat?

Vermonter_2

I'm going to replace my Pressuretrol with a Vaporstat and would like to know how to correctly set it. Anyone know a good method to calculate the correct settings?

mel rowe

I'm a HO with a little knowledge, mostly fromn the Wall and TLASH, and some experience the last few years, while working on my own 1 pipe steam system. I recently installed a Vaporstat as a replacement for a Pressuretrol. I have tried several setings, and currently running at a cutout of 8 oz. and a cut-in of 4 oz. I think I remember that the lower level should be just enough to get steam to the farthest radiator. I think the differential can be adjusted to whatever level works best with your system to prevent excessive cycling at the end of the overall heating
cycle. Of course the amount of cycling at the end of heat cycle depends on a number of things, including the EDR of your system compared to the capacity of your boiler. It can also be affected, I think, by how well your rad venting is balanced and also the venting of your mains.

Jamie Hall

settings

Mel's got it about right, seems to me, except that mine (I'm a building super, not an expert) is set at 8 oz. cutou and 1 oz. cutin. Seems to work fine -- good big building, too. So long as the farthest radiators heat, you're fine.

Not really much you can do about cycling at the end of a firing cycle, but that should only be a problem at the end of a temperature increase from a setback.