Steam radiator valves

mikechan

Recently I came across some steam radiator valves my customer wants replaced.
They are piped in at the top of the radiator, they have levers with an indicator and the vent is built rite in, any ideas where we can get new valves? They have the letters HSCo on them.

KC_Jones

Why do they want them replaced?

Grallert

Boy I could use a few of those. Must be on a vacuum system? Really nice valves.

Jamie Hall

KC_Jones said:

Why do they want them replaced?

That's a very good question! Those are very high quality valves and are darn near bulletproof. HSCo is Hoffman Specialty -- this may be (or may have been...) a vapour system. What's on the other end of the radiator -- or the bottom of the same end? Any outlet device? Pictures, please?

JUGHNE

Is there a trap on the outlet of the radiator?
These could be an orifice valve that controls the steam flow such that no trap is needed.
With a standard non orifice valve you would probably have to add a trap.

MilanD

That picture up there almost looks like a framed piece of art work. More I think of it - it is!

JUGHNE

Also, how do you mean that the "vent is built right in" ?
An air vent built into the supply valve?

Jamie Hall

JUGHNE said:

Is there a trap on the outlet of the radiator?
These could be an orifice valve that controls the steam flow such that no trap is needed.
With a standard non orifice valve you would probably have to add a trap.

Quite so. That valve, if it is the model I think it is, has an adjustable orifice arrangement so it can be sized after installation to the EDR it is serving. So long as the pressure is kept low -- not more than 10 ounces -- no trap should be needed -- although one was commonly used anyway (and in that application, the traps last forever...).

gerry gill

Whats wrong with them that they want to replace them?

KC_Jones

If you do take them out and replace them with something that most likely won't work correctly. I will take the old ones off your hand, or I'm sure someone else around here will.

To my knowledge you can't replace them, but could possibly rebuild/fix them if something is broken.

I'm sure @Steamhead or @Gordo knows what to do with them.

Gordo

@mikechan : Here is a YouTube video showing a few tips on dealing with the 1925 version of the Hoffman #7 which I have made my particular study. I hope you find it useful!
https://www.youtube.com/watch?v=NteDQtbL8qU&t=553s

gerry gill

thats a great video Gordo !!! Your the man !!!

LudgerHentschel

The video above is extremely helpful! Thank you.

One of the radiators attached to our 2-pipe steam system appears to have the newer version of the valves shown in the video. (See pictures below.) The radiator is the only radiator in our heating system that is essentially cold. Only on the coldest days will a few sections closest to the inlet get warm -- not hot.

At some earlier stage, someone installed a steam vent on the far side of the radiator. I have removed that vent temporarily and can confirm that the vent passes air. Eventually, I would like to remove this vent permanently. For now, however, I have reason to believe that air can escape the radiator in order to make room for steam.

That makes me suspect that steam is not allowed to enter the radiator. Hence my focus on the inlet valve.

I have turned the valve handle to the fully open position. In the photo, I have removed the valve handle to better show the dial.

The video shows that the valve "cartridge" can be twisted inside the housing to calibrate the valve capacity. Is there a reliable way of telling when the cartridge is aligned for maximum opening? The dial showing "open", "shut", and intermediate positions is carefully indexed to the cartridge. Is there are reliable link between this dial and the interior opening? I have tried a few positions without much change. (I have been hesitant to fully disassemble the valve, for now.)

The radiator is at a corner of the house and may have its own dedicated, fairly long supply and return. I think I have located the supply and return lines in the basement. There is steam in parts of the horizontal portion of the supply before it goes up to the radiator. But the steam does not pass through this supply line. All the other radiators in the house get steam. The cold radiator is on the second floor. We have hot radiators on the third floor.

Should I keep focusing on the valve? Should I take the valve out for additional inspection? Should I think about other potential blockages/issues?

Thank you,

Ludger

Jamie Hall

That is a Hoffman radiator valve. The interior cartridge is intended to be set for the size of the radiator, and left that way -- just like an orifice. Then the exterior handle is used to adjust from no output to full output, according to the desire of the occupant of the room. The correct adjustment of the interior cartridge is simple enough to perform: get the system as a whole up to operating pressure (usually around 4 OUNCES per square inch) and set the cartridge so that the radiator is around 90 % hot. Lock it in place and leave it. Put the handle back on.

Now... since it is possible that that cartridge position has been fiddled with, you will need to adjust it so that it is open all the way and look it in place, unless you want to adjust it properly. Then use the exterior handle to adjust the output.

Now if, when the interior cartridge is adjusted for maximum output you still don't get steam, you have a different problem, and the first place I would look would be the trap. Has it failed closed? Are you sure it hasn't? Then if you still have a problem, take a look at the return: are there any sags or low points in it which might prevent air from passing back to the dry return? I so, fix them. Finally, are you sure that steam can really get freely to the radiator? Check the runout -- again for sags or anything else that might keep steam from passing.

Now... that valve is from a Hoffman Equipped Vapor System. Is it the only one like it in the building? Are there other traces of the vapour system present, like the crossover traps? Maybe a Differential Loop? And are you running at a low enough pressure? Those systems worked poorly -- if at all -- at anything over 7 Ounces per square inch supply pressure at the boiler.

LudgerHentschel

Thank you for the quick reply.

We have a (Dunham) vapor system. It usually runs at pressures between 2oz and 3oz per square inch, measured at the boiler. That appears to be true now. All the other radiators in the house get hot -- thanks to lots of help from the folks here.

This is the only radiator that does not work properly. The radiators have a mix of valves. About half of the radiators have valves similar to this one.

I don't see a trap on this radiator. We have radiators with external traps that I can see. The radiators with this type of valve, however, don't have visible traps on the outlets. I presume there is a trap somewhere on the radiators. But I don't see it.

There is a crossover trap in the basement. That seems to be fine.

I am less focused on the radiator trap and the return line because the cold radiator has an open steam vent on it. On the far side, air can escape. (Once I am confident steam can enter the radiator, I hope to remove the vent and let the return pipes do their job.)

I will look more carefully for sagged supply lines in the basement. The lines looked OK, but I will use a level to check more carefully. The supply pipe is a 3/4 inch (or 1 inch) pipe. It would not take a lot of sagging to create a complete water blockage in a small pipe like this. Moreover, it probably does not take much water to block 2oz steam. I will check and report back.

Thank you,

Ludger

dopey27177

If I remember correctly, The system these valves were used on were were vapor and vapor vacuum system.

These valves were for the home owner or user to regulate the heat in the room or rooms.
If a room was to hot the user turned the valve to a lower setting (partly closed), The valves had graduations on the top of the bonnet so the user would know the setting they liked. Unfortunately in some of the jobs that I consulted on the valves were painted over several tines and the settings were not visible also the valves were stuck in the full or near closed position. These valves had packless glands and heating the body to get rid of the paint would ruin the packless gland.

What was done was to use chemicals to soften the paint and a wire brush to remove the paint. Once done most of the rad valves were good.

The best replacement for the valve is made by Mepco which is an orifice valve, That valve orifice setting once done is not adjustable, but is needed to regulate the steam flow in the rd. That is important if the radiator does have a steam trap.

See Attachment

Jake

Jamie Hall

I might add that that small supply pipe isn't going to be helping at all... even if it is perfectly pitched.

LudgerHentschel

Progress!

There indeed are "tick marks" on the dial. If I squint at the valve (or the picture), I can see several marks between the "shut" and "open" marks. Apparently, those display the EDR capacity of the open valve when lined up with an external mark. After removing the valve from the top -- easier than I was expecting -- the external mark apparently is the inlet into the radiator. As positioned in the photo, the valve is effectively shut because the internal opening points 90 degrees away from the radiator. I now have turned the valve cartridge 90 degrees counterclockwise to align the cartridge opening with the radiator inlet. The valve piston is in the fully open position. Let's see.

I also took my level on a chase for sagging steam pipes. Turns out there are some water pipes crossed over the middle of a long supply run. I suspect both the steam supply and the water supply are original to the house -- about 100 years old. Over time, this had turned into a low spot on the steam supply -- maybe by 1 inch or so. The pipe is 1 or 1.5 inches in diameter (it's insulated). I have propped up the water pipes. Now the supply line appears to pitch toward the vertical supply riser, starting all the way back at the junction with the main.

While the valve cartridge was out, steam rose through the open supply pipe at the radiator. For the first time in a long time, the entire supply line got hot. I think that's a good sign. But it did not happen until late in the cycle.

I removed the **** vent and could feel air venting from the far sided of the radiator. As a result, 4 or 5 of the 17 radiator sections heated up. But the steam arrived quite late in the cycle.

Let's assume that there was some water in the supply line. Am I correct in thinking that it may take several steam cycles to fully remove the water remnants and restore a full flow of steam to this radiator? I don't hear any banging in the pipes, but the steam coming out of the open radiator connection "burps" more than it flows -- for now.

Thank you,

Ludger

Jamie Hall

You're making good progress!

LudgerHentschel

The radiator now heats 4 or 5 out of 17 sections before the boiler shuts off on temperature elsewhere in the house.

Between the valve correction and the steam pipe straightening, steam now gets to the radiator.

Thank you for the very helpful suggestions.

But the steam arrives at this radiator quite late compared to the rest of the system. (The rest of the system is quite fast.)

This sort of makes sense to me now. The slow radiator is the only radiator at the end of a very long branch of steam pipe. The branch is not vented in the basement since there is no "drop" for this branch. The associated main is vented long after the branch point, when the main drops.

Based on that, I have concluded that the vent on the radiator is supposed to be there. It vents the air for this branch. I have ordered a new and larger vent. I don't think that will make much difference because the tapping is only 1/8 in. Even with an open 3/4 in supply pipe, the steam is slow. But the larger vent is an easy experiment.

If the larger vent is not effective, there may be better ways of venting this branch. I am reluctant to slow down the other mains. I will have to think about that before I ask more questions.

Thank you,

Ludger

ethicalpaul

If you have an open 3/4" pipe up there for testing and it's still slow to get steam, that points to that supply pipe having a "sag" or "valley" that is collecting water which will greatly delay the arrival of steam to that radiator during a call for heat.

Either that, or all your other radiators are insanely fast.

But additionally, don't gauge this by how many sections heat up in a radiator...that is really not paramount. What you should be observing is how comfortable is the room that has that radiator. The radiator could be vastly oversized for the room, or the room could be getting heat from other rooms, all that can affect how fast or slow you want a radiator to fill.

LudgerHentschel

I think I straightened out the supply pipe. I have moved a long level along the pipe to confirm that it is straight again and pitched up toward the vertical supply.

The basement steam branch for this radiator is a 1.25 in pipe. It used to have about a 1 in sag in the middle of a 20 foot run. I think that works out to quite a bit of water that might have been in the pipe. There could still be some water in there. I presume that will get steamed out over time. If there is still water in the pipe, I presume that takes a lot of energy and delays the steam until the pipe is "dry" again. Unfortunately, I can't observe whether there still is water in the pipe. Is there anything obvious to check or do? My plan was to wait for some time and see if the steam gets faster.

The room could use more heat but is OK as is. As you mentioned, there is a radiator in the next room that is working well and shares heat with this room. The room is not large but has window walls facing north and east. On cold days, this is the coldest room in the house.

Thank you,

Ludger

LudgerHentschel

Forgot to mention: there is no banging in the pipes.

ethicalpaul

The water won’t dry out if there is a valley for it to lie in because every heating cycle creates new condensation to fill it—it must be able to drain.

But you do the best you can to ensure the pitch is right and things are working ok. If it’s just a little water in my experience it may not hammer but still may delay the steam