Less than quarter inch was all it took to end the hammer

agurkas

I am just blown away how sensitive single pipe systems are. There was one radiator driving me nuts. I would get random hammer in it. Sometimes in the beginning of the heating cycle, sometimes in the middle (though never in the end). It also happened to be radiator in my toddler's room. Not good.
After reading "Greening Steam" just chose to reseat the valve and raise the rad by quarter inch more than it was before. No hammer yet two days and counting.
Happy hammer is gone, but not looking forward to continued use of the system. If little something like that makes such a major difference, that makes somewhere else little change will cause trouble again to be chased down.

Jamie Hall

Steam systems are actually pretty forgiving. Up to a point. In the case of your toddler's radiator, you found that point: the radiator wasn't draining properly (probably when you raised it you changed the slope of the runout enough to allow it to drain).

Which is not to say that you may not have other problems elsewhere in the system. There are sort of two rules: if it ain't broke, don't fix it and, if you change it, make sure that the change makes things better, not worse.

vaporvac

Jamie had a similar experience, but on a very long run of rad. It is amazing what a difference a small change can make, but I guess that's physics for you.

agurkas

Still have my wife very unhappy with hissing of the vents on the rads... that is another battle for me with this old beast. Those extra vents I am putting in may help.
Starting to diagram the system and, when compared to what I have learned from the books what proper design should be, I am scratching my head wondering how much of a money pit this system will be. Years of additions and changes made it a frankenstein with several hundred feet of pipes.

Fred

While you are adding those vents on the mains, double check your operating pressures on the Pressuretrol. The Cut in should be about a half pound (.5) and the Differential should be 1 pound for a max operating pressure of no more than 1.5 pounds. Between the vents and the pressure setting, those radiator vents should be silent. To your comment about not looking forward to continued use of this system, if you give it a chance, you will come to love the even, clean heat a steam system can provide. It does take a bit more maintenance than a forced air system but well worth that effort and besides you still have the blower motor noise to contend with.

agurkas

I am installing mini-splits for all bedrooms. Going to reduce the need for the system. Quotes I was getting to make it right were just so high.
Will see what happens with some more vents (cut-in was 1st thing I lowered to that standard) and proper insulation of those pipes. Right now every elbow is exposed, half of the system is in the crawlspace, and whatever insulation is on it, it is the 1/2 fiberglass stuff that was probably bought 20 years ago. At least it is not asbestos.

BobC

I have lived in this 96 year old house for 33 years and in all that time I've only had someone in to fix something on the steam system once. I do have someone in to clean and tune the system and I've replaced the boiler once when the 50 year old one died and recently when the oil tank started to weep and I decided to move to gas.

I have replaced vents, shimmed radiators, and replaced a failing pressuretrol with a vaporstat. You may have to play catchup if a system has suffered from neglect but I don't think you will ever find a system as reliable and long lived as a steam system. Old houses settle and can cause problems. Minisplits are great but they are decidedly not trouble free - too may parts.

Bob

gerry gill

steam is all about subtleties

agurkas

What is advantage of vaporstat over pressuretrol?

BobC

a vaporstat allows the system to operate at lower pressure (below a pound) than a pressuretrol (1-1/2 pond minimum) does.

Bob