Stumped re: Non-Functioning Radiator

mblucas

Hi--We've consulted with top professionals in the area and still haven't found a solution for this problem yet, so I'm trying here. I apologize if this seems a little long or redundant with other posts (I think it will sound familiar, but we've gotten such contradictory information from good people that I want to start from the beginning).

The Setup: We've had a non-functioning radiator in the master bedroom of our 2-story house since we moved in 15 months ago. All other radiators in the house heat up quickly and get very hot (11 radiators in the house total). The bedroom radiator that doesn't work is the farthest away from the boiler. It goes through a riser up through an under-the-house garage with a couple of bends and 45 deg. angles. The pipe tends to get hot around one of the elbows and then seems to stop just before it gets to the riser that enters the plaster of the garage ceiling. The non-functioning bedroom radiator is sectional--it's long (maybe 5-6 feet), with multiple iron sections screwed together.

Some clues:: Last year, we occasionally got heat from the bedroom radiator if we were away and the boiler was bringing the whole house up from, say mid-50 degrees to 68. Whenever the radiator started to get hot, we would hear loud rushing water sounds around the radiator and in the walls. Occasionally, we would get extreme water hammers in the walls below the bedroom--loud enough that I shut down the system and was afraid the pipes would break through the walls. This year, we've had no water hammers or rushing water sounds, but the radiators still doesn't work.

Potential solutions: Last year, I replaced most of the vents in the house with adjustable vents and tried to balance the system. I also installed two new main vents near the boiler. That hasn't worked. We had a master plumber here and another service person who shut down all of the functioning radiators and turned the thermostat up to 80 to test the bedroom radiator. Eventually, the radiator got hot (it took a fair bit of time). They suggested that I try to purchase new vents and balance the system. I have talked to two other professionals who both seemed very knowledgeable and have suggested the following solutions:

Tech for company that manufactures radiator vents: Suggested using something called a `candelabra' to add ports for additional vents for the longer pipe near the boiler. He said I need that section to vent quickly, and it can help to install 2-4 vents on that pipe. I thought this sounded like a good idea, but I don't understand the setup yet, and two plumbing supply companies in the area said it didn't sound familiar when I described it (they didn't know what part to sell me).

Owner of plumbing supply store: He said there's a good chance that I have corrosion or water in a pipe. I was convinced that this was the problem last year, and a relative and I even took off one of the elbows in the garage and tried to snake the pipe, but we couldn't get the snake around the second elbow. The owner of the plumbing supply store said what the relative and I were thinking of trying last year: since the pipe goes into the floor and walls, and is probably wrapped in asbestos once it disappears, we can only access it from the garage or the radiator valve. He advised us to remove the radiator valve and to snake it from the top to the garage below. It seems possible to me that there is also corrosion or water in the radiator, and I'm not sure how to assess that, or, if necessary, to get it out (again, it's very long and has multiple sections). I ran the corrosion theory by the master plumber and tech guy who was in the house, but he said he didn't think that was the problem (and, again, said it was a venting issue and that the vents had to be balanced).

So, do we keep working on balancing the 11 vents, add some kind of T to the iron pipe near the boiler to add vents, or clear out a likely clog and/or corrosion in the pipes? Or something we haven't considered yet.

Thanks everyone.

mblucas

To moderators: this probably belongs in the `Strictly Steam' section, but I don't see an option to move it. Apologies (first-time poster). Please feel free to move it.

Abracadabra

If you shut off all the other radiators, do you get steam to that "non-functioning" radiator?

BobC

It sounds like the boiler isn't running long enough to get steam all the way to that radiator. The tech who told you to add more venting to the steam mains was probably right on the money.

We need to know about how long the steam mains are and how many of them the system has. We also need to know what kind of vents the steam main(s) have right now, take pictures of them and post them here.. We can then tell what kind and how many vents you should have.

Is there insulation on the boiler piping and steam mains right now? If there is no insulation that is delaying the distribution of steam. Those pipes need 1" of rigid pipe insulation on them.

And lastly what kind of thermostat does the system have?

Bob

Jamie Hall

If get -- or got -- water hammer or rushing water sounds, there is water trapped in there somewhere. The most likely culprit is in that section that is hard to get at. The pipe doesn't have to be full of water for there to be a problem -- just pitched the wrong way, so that there is a puddle or pool.

Additional venting may help -- but I surely would want to check the pitch of every piece of pipe going to that radiator, to make sure it really was in the correct direction and adequate.

mblucas

Abracadabra: Yes, but it was slow and we had to turn up the thermostat to 80.

BobC: I'm trying to get some pictures now and will post them in a bit. The thermostat is old and definitely nothing fancy, but it does seem to work well. The brand is Maple/Chase.

Abracadabra

Pics of the boiler and piping around it please.

Fred

I'm with Jamie. If you hear water and/or hammer, there is likely a horizontal section of pipe, either in the basement or in the ceiling of the garage/ under the bedroom floor that is pitched the wrong way and holding water. You may benefit from additional main venting but I seriously doubt that will completely fix this problem until you find where the water is pooling. What size is the pipe supplying steam to that radiator. Did that radiator ever work consistently? There is also the possibility that the supply pipe isn't large enough to both supply adequate steam and allow condensate to return, at the same time.

mblucas

I've posted some photos, but I'm not sure if they're from helpful angles. One shows the location of the two main vents. The pipes with the bends are the garage area where the riser goes into the garage ceiling (the bare pipe is the one we removed and replaced--we couldn't get a snake around the second elbow). The remaining pipes are inside the basement, which is separated from the garage by a wood-panel wall. Thanks.

mblucas

The second photo from the top, which shows the bends and bare elbow that we removed, also shows our `dog bowl' solution for ensuring that the pipe is pitched properly. All of the visible pipes appear to be pitched correctly back to the boiler, and the radiator itself is pitched properly. Everything else would be risers, I assume, through the ceiling and floor (where pitch shouldn't be an issue, right?).

Fred

I'm not sure what those vents are , Maybe Vent -Rites? That probably isn't enough venting. How long and what diameter pipe for each Main? All the horizontal runs look really level. Is there any pitch to those mains and returns at all?

BobC

If the problem radiator is on the second floor there could be a horizontal pipe under the floor you can't see and that could be sloped wrong.

If you suspect that could be the problem you could try to shim up both ends of the radiator by 1/2 or so, that could correct a slope issue under the floor.

Can you read any numbers on those vents? They might be ventrite 35's which have pretty small vent rates. Depending on the length of the steam mains bigger vents might be in order.

What pressure is the boiler running at and does the water level seem reasonably level when it's making steam?

Bob

Abracadabra

Think you need better main venting.

Jamie Hall

Woof. If the second pipe in that sequence -- the one parallel to the main ending at the dog bowl -- is level or pitched slightly wrong (and it looks as though it might be) that's not going to help. At all...

mblucas

The mains are Vent-Rite 77s (new as of a month ago). If we add venting, how do we know which pipe it should go on? The pipes to each rad are 1 1/4", but I'd have to look at the mains again to check. I'll also get a level to double-check the pitch of the mains, but I think the master plumber did check all of that.

If we want to add vents, how do we know which main to add them to? Would it be the pipe that goes to the problem radiator?

BobC--thanks. A problem with a pipe in the floor has been a worry, though it didn't occur to me that we might have a horizontal pipe that isn't pitched properly.

I'm including a photo of the radiator, in case that's helpful.

mblucas

Also for BobC: Any advice on how to shim up a radiator of this size? And you think we should try both sides, in case the problem is a pipe under the floor?

BobC

That radiator is mounted to the wall behind it on brackets so the brackets would have to be moved up. You might be able to put temporary shims between the existing brackets and that convector to see if this theory is correct.

is the waterline in the gauge glass stable when the boiler is making steam? Has the boiler been skimmed recently?

I believe you have two steam mains, approximately how long are they? The idea is to vent the steam mains very fast and the radiators slowly but we have to take care to vent the steam mains somewhat proportionately and that is why we need some idea about their length.

Bob

mblucas

Bob--it's interesting that you bring up the gauge glass. In the last couple of months, the water started surging (bouncing). That's new this year. The oil company skimmed the boiler, but the glass is still bouncing. (It looks like the pressure gauge no longer works either.)

I'll get help tomorrow to measure the mains. I'm not sure I follow what I should be measuring (where the mains begin and end). Thanks...

BobC

If the boiler water is surging it means the water may have oil in it and perhaps the steam pressure might be too high. Has the pigtail under the pressuretrol been cleaned recently? The pigtail is supposed to isolate the pressurertrol from live steam but because it's such a narrow pipe it can get plugged up. If it gets plugged the pressuretrol can not see whats going on inside the boiler and it loses the ability to control the boiler pressure and that can allow the pressure to go too high. The pressure gauge maybe installed on that same pigtail so if it were blocked that explains why the gauge isn't working any more.

The water in your sight glass looks pretty dirty, the boiler should be drained and flushed to get rid of any sludge and the sight glass should be cleaned also.

Have someone cleanout the pigtail and make sure the pressuretrol is operating correctly. Also have them skim the boiler to get rid of any oils in the water that can cause an unstable water line. Skimming takes a few hours if it's done properly. That boiler has a skim port . There is a plug above the boiler power switch where the skim port is usually installed so I wonder how they skimmed it with that plug still in place?

The steam main is a large pipe that comes off the boiler header and works it's way around the basement with radiator pipes coming off of it. You said there are two main vents so I assume you have two steam mains.

i can't really see whats going on above the boiler. Take a picture from the side that shows the top of the boiler, the boiler outlet and it's header along with the connection to the steam mains.

Bob

mblucas

I'm posting another photo, Bob, although I still don't know if I got the angle right. I'm honestly still not sure where the mains begin and end.

The boiler just had an annual cleaning. After that, the service manager and master plumber came out to assess and said they skimmed unit. It did take awhile, but I'm not sure it was hours. It has seemed odd to me that after a cleaning and skimming, we still have such dirty water in the sight glass, surging water in the glass, and a non-functioning pressure meter. The service manager did say the pigtail might need to be cleaned, but I'm not sure if they did anything there. They also raised the pressure slightly, which I understood to be an effort to get steam moving to the cold pipe.

I'll keep adding photos if this one doesn't show enough detail.

Main issue is that several experts have looked at system and there's just no consensus (balance vents, add main vents, shim radiator, snake the pipes!).

mblucas

Just found this discussion. Sounds like same kind of radiator, and same problem. I'm inclined to look into how to remove it and get it cleaned.

http://forum.heatinghelp.com/discussion/145747/clanging-gurgling-from-recessed-convector-radiator

KC_Jones

Raising pressure is wrong. You had an annual cleaning and they didn't check the pigtail? That should be automatic.

You need more main venting for sure. Measure the mains where they start at the boiler coming off the top on the header. The end of main will be after the last radiator and where the pipes start heading back to the boiler.

Looking at the piping running to the problem radiator I would take a guess and say you should add an additional vent to the inlet side of the rad on the pipe. This will allow you to vent the riser quickly and get steam to the rad at the same time as the others.

Until you get the venting correct I wouldn't think about cleaning anything. It's extremely rare for a steam pipe to have a blockage, wet returns are typically the only place a blockage can occur.

On a side note I would caution you with calling the people you are dealing with "experts". Anyone that raises pressure like that doesn't know steam. Where are you located? We may be able to recommend an actual steam expert in your area.

mblucas

Thanks. I'm in central Massachusetts. It would be terrific to have a recommendation.

mblucas

Thanks--I'm closer to Worcester though. Would be great to find someone nearer.

New England SteamWorks

Replace these two vents with 2 (or 4 depending on the size and length of the mains) Big Mouth vents.



Take a better picture from a different angle of this take-off:



What size is the pipe when it takes off from the main in the circled area, and does it reduce afterwards as it goes to the dog bowl and eventually up into the ceiling? How long approximately is this entire pipe from the take-off to the radiator? The union leads me to believe this take-off was possibly altered.

As an experiment, remove the convector vent completely and fire the boiler and see what happens:

mblucas

Thanks RI--won't be able to follow up 6-8 hours or so, but will post more photos of that junction and measurements for mains (now that I understand what they are). That section always seemed to me to be much more complicated than the rest of the system.