Is this a Naturally Induced Vapor System?

pbkrag

I just bought a new house. It has steam heat. A new experience for me. I've been working my way through Dan Holohan's books, and have been trying to see what I need to get this system running right. It does heat the house but I suspect it needs some work. I've replaced a supply valve on one of the radiators and have a couple others that are leaking and need to be replaced. I noticed that some of the radiators in the house don't heat up all the fins, some do. I'm not sure if there's a main vent valve I haven't been able to find one yet. Also, I think these valves on the radiator vent outlets aren't working right. I loosened one and it let the air out and the whole radiator heated up nicely. So, I was thinking these might be from a vapor system. Should they be removed and replaced with a standard air vent? (One of the previous owners did this with one of the other radiators.) If so, anything special I need to do with the piping? can I just remove the unused pipes, or do they need to be capped off? I don't see anywhere that these vent lines go back into the steam lines. Also, the pressure is running at about 8 psi so that should probably come down.

Steamhead

That's an air-line system, also known as the Paul system. There is supposed to be an ejector where all those air lines come together, that pulls the air from the radiators. Take a pic of the boiler area and also where the air lines end, probably near the boiler, and let's have a look.

I think they still make those air vents that stop steam from reaching the air lines- ISTR Hoffman's version is called the #3.

gerry gill

Yes its an air line one pipe system as Steamhead said. The vacuum means can be re-installed with a water venturi if someone gutted it. We restored one once that way. Good thing the lady likes it hot, thats all i have to say about that

pbkrag

Following the lines I see nowhere where it goes into any type of device. I only see one place where a line was capped, that might have been attached. the line runs the length of the basement, and at each end turns to run the width. I cant see these ends as someone has finished off that side of the basement. The only thing visible to me that could allow the line to vent is one these airlines comes up from the floor, and rather than connecting to the radiator it has a air vent on the end. (see pics) The vent was stuck shut. I freed it up a bit but never saw or heard anything vent from it. It above the finished part of the basement so I can't see whats going on underneath. The pressuretrol looks to be set at .5 psi for the cut in and 2 for the cut out. But after it heats up the gauge says 8 or 9!? Also, I still haven't seen a main vent on the steam supply, maybe it's at one of ends i cant see. Rather than restoring the vacuum can I just put vents on the radiators? Someone appears to have done that to one of them.

gerry gill

Yes you can vent each individually and turn it into a standard one pipe system. Back when it had a negative pull on that air line it was highly efficient.

pbkrag

Thanks, Maybe I'll vent each one this season, and spend the winter reading and learning on how to restore the vacuum. Any thoughts on the pressure? Is it more likely the gauge is off or the pressuretrol is broken?

BobC

The pressuretrol should be turned down to 1 not 2 but pressure gauges do go bad. If the pressure gauge is not on the same pigtail as your pressuretrol the pigtail could be blocked - meaning the pressuretrol does not know what is going on in the boiler.

Take the pressuretrol off the pigtail and make sure the pigtail is not blocked. Make sure you kill the power first because there could be 120v on the pressuretrol terminals. If the pigtail is good mount a low pressure (0-3PSI) gauge on a separate pigtail and see what is really going on. If the pressure climbs above 3 PSI the pressuretrol is bad.

Bob