pressuretrol settings/vaporstat needed

zippydw

THis is that 2 pipe system I talked about before.It is two pipe. We have been operating ont he assumption that it is a 1907 vapor system. Discovered under lots of paint that Returns feed into a McDaniel Suction tee hooked up to a large evacuator pipe that flows into the condensate. Have not gound any vents. System is not heating enough to satisfy the tstat, but has worked like a champ in the past.I hate to say it, the system always had steam leaks. This is the first winter without them. Spent alot of efffort to correct them. They could have been my venting!

Paid some attention to the pressuretrol. Pressuretrol indicates it is subtractive. But the guy who set it put the main at slightly above 0 and the differential at 1 1/2. If this is a true 2psig 2 pipe I would set the main to 1 1/2 and the differential at 1.

However, with that evacuator and suction tee. would that be correct. Franco suggested changing to a vaporstat. But is that appropriate with a Suction/evacuator return?

The more I learn on this thing the stranger it gets. If anyone wants to see photos, there are lots on the "really old 2 pipe system" thread on the wall.