Pressuretrol vs. Vaporstat

Gene_2

Our 1922 one pipe low pressure steam system is getting an early Christmas present: A vaporstat to replace the pressuretrol, which is currently cranked down to 1/2 psi cut-in and 1 psi differential.

There are 2 vaporstat models: the L408A1157 has a 0 - 4 psi pressure range, and the L408A1132 has a 0 - 16 ounce/sq.in. range. Which one should I get?

I'm confused by Dan's discussion on page 14 of "The Lost Art of Steam Heating." He says to set a Pressuretrol to 1/2 psi cut in and 1 psi differential, but then he says if you have a Vaporstat, set it "to Cut In at about four ounces and Cut Out at about ten ounces."

But in the preceding discussion, he says the radiators need 1 psig to heat the house. And my piping losses are probably around 2 ounces (longest run is about 85'). So don't I need a cut out of 18 ounces/sq. in.? You can't set the 0 - 16 oz./sq/in. Vaporstat this high.

Bob W._3

FWIW this is my thread on the same issue earlier this week:

http://forums.invision.net/Thread.cfm?CFApp=2&Thread_ID=29290&mc=6

Steamhead (in transit)

Get the 1-PSI Vaporstat

If the house has had any insulation, storm windows, weatherstripping etc. added you don't even need 1 PSI at the rads. Ounces rule!

Patrick Linhardt, \"Linhardt's Field Guide to Stea

go low

Hi Santa,

What a nice present for a steam system. Pick the 0-16 oz. and try to operate around 8 oz., that will be enough to heat the house.

Things to add to the Christmas list:

1) Lots of new vents with plenty of capacity. The system will need plenty of venting to keep the burner from cycling on the pressure control.

2) A professional burner tune-up to peak your efficiency and make sure you are not over-firing. Too much steam can also make the burner cycle on the pressure control.

3) A thermostat check up to make sure that it is set for your steam system. You want to avoid the t-stat cycling the burner during a call for heat.

Best regards and happy shopping, Pat