Know anything about steam heat?

jmebonner · November 12th, 2003, 08:37 PM

We're in our new house and everything is swell but one thing. The house has steam heat, like from the 30's. The first three radiators on the circuit get hot, but the last three don't. Anyone have any experiences?

The boiler also seems to short cycle, so I thought that may be part of the prob?

I'd hire someone to come fix it, but no one in town really knows a lot about them, so I'll just be paying them to guess

Thanks!

Theophylact · November 12th, 2003, 08:54 PM

Steam, or hot water? We have have gas-fired hot water heat.

You may have to bleed the radiators. Newer ones have a finger-operated valve; older ones have a valve that takes a little key like an old-fashioned skate key. With the heat on, you open the valve to bleed air out and let the radiator fill up until water comes out.

RayH · November 12th, 2003, 09:48 PM

You may have a vapor lock. How hot is the water during its run. Where does it start to get cold. You have to get where the water is. Maybe you have a leak in the system.

jmebonner · November 12th, 2003, 10:02 PM

Theo,

It's steam, a one pipe ystem, supposed to run @ 3 lbs of pressure. I did wonder if I might have to bleed the system, but don't know where to do so. The system's from the 30's.

Ray,

I thought maybe so, but the pipes under all the radiators are hot. No leak to my knowledge, the water level is constant, never any need to add. During the run it's quite hot. Too hot to touch anyway.

Thanks for the help, keep it comin!

RayH · November 12th, 2003, 10:43 PM

Be sure you only grab the hot pipes under hand and under the pipe. If the pipe gets too hot, it will force your hand open and drop away from the pipe. Grabbing the pipe over the top will also open your hand. But it will rest on the pipe!

The units look fancy. But they are actually very simple. They are just a continous pipe with a STEAM TRAP valve. They get old. They can be replace with industrial, brass types. You can add a drain pipe to the industrial ones and save your floors!

http://www.armstrong.be/prod/traps/trapsmain.html

You probably have more than one problem. But a start is the globe valves to admit the steam in each of the units may be stuck shut. The stem may be rising. But it may not be connected to the gate any longe

These become messy jobs. After you block in the water, you can remove the valve and use a short pipe nipple to connect the radiator to the main supply in a straight through. If the heat goes through, then the valve is broken. If not, there is a clog in the radiator. Maybe rust. Maybe vapor.

Actually, sometimes these globe valves come apart and new parts can be substituted. But the problem is that particular valve may not have parts available. You'll have to swap the valve.

Use pipe UNIONS to replace the valves. Usually, in homes everything is orignally put in so they can't come out. Just break the pipe and rejoin them with unions. You see them on water heaters.

http://www.smithfast.com/bpunion.htm

no1_vern · November 12th, 2003, 11:02 PM

Rayh got the important stuff, I agree it might very well be the valves in the system, and that you should check them first.

jmebonner · November 12th, 2003, 11:10 PM

Ray, I too suspected those valves. Is there any way to test them? Like, say, take the ones off the units that work and put them on the ones that don't and vice versa? Or by blowing in it or anything? I can blow on the trap and raise the little lever and air gets out both ways, but upside down I get nothing, like a check valve is in there or something.
Anyway, thanks for the link to the traps, I'll check it out.

EDIT: I was thinking of the air valves on the end of the radiator itself, nothing on the inside. Blech, I'm starting to get confused

Ojay, another question, the vent at the end of the system, right before the wet return, is there any way to test it? And is theis the one you mean Ray? Any links to some steam info for boneheads like myself?

I looked on amazon.com for Steam Heating for Dummies but they were sold out

RayH · November 12th, 2003, 11:37 PM

Do A Google Search for STEAM RADIATOR AIR VENTS!

The globe valves aren't a terribly expensive proposition. The trouble is that they may be rusted on!

jmebonner · November 12th, 2003, 11:56 PM

cha-ching, thanks Ray!

RayH · November 13th, 2003, 05:20 PM

I grew up in a place with steam heat. I've worked in an oil refinery where steam was used as a process. I've seen the old fashioned ornate radiators replaced with more modern units.

Write to these people: http://www.steamradiators.com/order.html They should be able to tell you how the devices work. Maybe tell them you might replace your old units! Or that you're considering an addition and want to know how these things work!