Can steam pressure ever be too low??

Billy_13

Hi All.
I made some tweaks to my steam boiler this fall. One change was replacing the "hissing" main vents. Replaced all my Hoffman main vents (74's and 75's) with Gorton #2's (3 main vents total). Also gave them all AT LEAST 8" vertical clearance from the main (previously were threaded straight into the mains). The overall pressure in the system dropped considerably- so low I couldn't detect it. I added a compound gauge and a 0-3psi gauge (kept the code-required 0-30). The pressure never builds up over 4 inches H ₂ 0 (~0.145psi) when firing; stabilizes at ~-0.07psi (vacuum) when idle (not firing).

Is there any downside to pressure this low?
I've read all of Dan's books. I cant even get the pressure up to 0.5 psi! Did I go overkill? Will I damage anything?
The results have been pretty amazing- the house heats much quicker and evenly... and my fuel $$ dropped nearly 300%... all in line with what Dan says in his books.

All replies welcomed.
Thank you all.
-Billy


Weil-McLain EG-75
2-Pipe Steam
Gravity-Return

KC_Jones

Ask @ChrisJ You have what you want low pressure. I think Chris gets way lower than that.

ChrisJ

Billy,

Here's a video showing my pressure at the boiler when it's 10F outside. Though since adding a snubber the overall pressure reading stays slightly lower. My system shuts down for 10 minutes if I hit 1" WC and it never does, as of yet anyway.



https://youtu.be/hH36luC9GKU

ChrisJ

To answer your specific question, can it ever be too low?
Yes, if you have problems with radiators not heating no matter what you do with venting, otherwise, no.

New England SteamWorks

Exactly. If all your radiators are heating, you're running a nicely balanced system. You're running right where you want to be, no overkill at all. Nice.

Billy_13

Guys,
Thank you all for replying. I can't tell you how good it feels to have that peace-of-mind. Got a couple below zero nights this week in the Steel City. Excited to see how this holds up- first winter in this house.
Thanks Everyone!
-Billy