hot pipe - cold radiator
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hot pipe - cold radiator
i have steam heat and have a cold radiator on the second floor. the pipe leading to this radiator is hot on the first floor so it would seem the steam is getting to (or close to) the radiator but the whole radiator, including the shutoff valve are cold on the second floor. the vent valve (new and wide open) does some hissing which leads me to believe that the steam is getting close and that air can pass through, but no steam is entering the radiator. the radiaitor pitch is half a bubble back toward the pipe (single pipe steam). the rest of the radiators in the system are operating fine. any thoughts?
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Cold Radiator
There are vents made for second floor radiators. They have a larger opening for faster venting. For a quick test you could remove the vent. When the rad gets hot about 1/2 way across or so, get that vent back in quick. You don't want live steam coming out. All this will tell you is if the rad is getting steam & you may need a larger vent.
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i'll give this a try
thanks grady - let me say first that all the other radiators in the house have the same vents. that said, i'll post the results after trying your suggestion. thanks.
#4

How old is the shut-off valve on the radiator? I've seen this type of thing before, and found the valve gasket had fallen off and landed on the seat. The flow was so low that the steam condensed before it got to the radiator. Replacing the valve did the trick. You did make sure the valve is fully open, right? Also, some vents, such as Vari-vents, are adjustable. Good luck!
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replace shutoff valve
i'm inclined to agree that this may be my best course, though i'll follow Grady's advice first. the shutoff valve is fully open and the vent is fully open (the adjustable type). i have no idea how old the valve is - i bought the home two years ago. how difficult is it to replace the shutoff valve? i have no experience with this - steam heat is new to me.
#6

They can sometimes be quite difficult to replace, and sometimes quite easy. It is hard to tell till you try it. Materials needed: REPLACEMENT VALVE - make sure it is the same size and type; TEFLON TAPE - 3/4" roll is prefferable, but 1/2" will work too; & SOFT-SET PIPE DOPE - not neccesary, but wouldn't hurt. Tools I reccomend having on hand before trying it: PIPE WRENCHES (2 minimum) - the bigger the better, I say (Ridgid brand is preferred, but can be pricey if you don't use them on a regular basis...24" and/or 36") if you know someone you can borrow them from, you can save some $$...I think some places rent them too; MAPP OR PROPANE TORCH - the hotter the better; SAWZALL - A few 6" fine toothed metal blades too; and a INTERNAL WRENCH -for removing the union that attaches to the radiator. I will continue tomorrow with instructions. My wife say's it's past time for me to come to bed.
#8

http://www.heatinghelp.com/seminars.cfm
#9

Ok, went off on a tangent, now I am back. I reccomend doing this on a weekday in the morning, so that if anything goes wrong, you can call your service company to help you out, and it won't cost you time and a half or double time. First thing you need to do to replace the radiator valve is turn the heat off, allow the radiator to cool (which I'm sure yours is already) & close the radiator valve. Next, disconnect the union between the radiator and the valve. I assume you know how to do that, but just in case, when you are over the valve with the radiator in front of you, turn the nut dovn and to the right (clockwise). It wouldn't be a bad idea to have another person there to help make sure the radiator doesn't fall over (I've only dropped one once, but hey, ya never know). Once you have the union apart, with help (especially if it is a big radiator), move the radiator to the side. Be careful not to scratch the floors. If you want to inspect the inside of the valve (does it really need to be replaced??), you can open it back up (just don't have your face in the way when you open it in case there is still pressure on the system) and look to see if the seat is ok or not. If it has fallen apart or off, I would just replace the whole thing. Assuming you have an angle valve, put one pipe wrench on the bottom pipe with the handle to the right and the jaw opening towards you. Put the second pipe wrench with the handle to the right and the jaw facing away from you on the knuckle of the radiator valve with the handle a little closer to you than the other wrench. Pull them towards each other. This is where bigger wrench = better. Don't hurt yourself trying to get it off. If it won't budge, there are a few tricks you can use. There are relief cuts you can make on the valve (take the sawzall and cut the knuckle of the valve parrallel to the pipe without cutting the pipe while getting as close to the threads as possible. This will weaken the brass threads and make it crack when you try again). Another option is, you can take the torch and heat up the valve till it is extremely hot and try again. This will loosten up the dope and threads making it turn easier. **Just be sure that if you use this method, you are very careful not to light your house on fire, bubble up the paint on the wall, burn your wall paper, or burn you!** You may also want to take an adjustable wrench and screw driver and remove the handle, nut, and valve stem first. The rubber part inside makes smoke when it burns. Once you have the valve off, you can take a wire brush or fitting brush (3/4" works good) and clean up the threads on the pipe. Next, if you are looking down at the pipe, wrap teflon tape on the threads going around it clockwise with the tape coming off the bottom of the roll. Put at least 4 wraps (6 would be better) on the threads keeping the tape taught. If you put a lot of teflon on, pipe dope isn't always neccesary. put dope over the tape in a clockwise motion (so as not to take the tape off). Turn the new valve onto the threads till it is tight (don't over tighten it or under tighten it) and pointing in the same direction the old one was. If you want to, you can now close the new valve (if it already wasn't) and turn the heat back on. I will be back later to let you know how to replace the radiator portion (if it needs it).
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Replacing radiator valve
hvac-emt,
Thanks for your instructions. i think i can folllow these without too much difficulty (fingers crossed) and hopefully the person who last had it apart was good enough to use teflon and dope. i do have a question, though. you say to look inside the valve to determine if it needs replacing. i've never looked inside one of these - will it be obvious to me if it needs replacing? what, exactly, am i looking for?
Thanks for your instructions. i think i can folllow these without too much difficulty (fingers crossed) and hopefully the person who last had it apart was good enough to use teflon and dope. i do have a question, though. you say to look inside the valve to determine if it needs replacing. i've never looked inside one of these - will it be obvious to me if it needs replacing? what, exactly, am i looking for?
#11

You will be looking for the gasket that attaches to the valve stem. It could have fallen and landed on the valve seat. Should be pretty obvious. It's been a while since I've done this. It could also be possible that the seat has totally disappeared (down the pipe?) Did you already try the air vent thing? Insulating the pipe going to the radiator should also help get the steam there quicker.
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valve
hvac-emt,
thanks for all this information. i'll not get to this until this weekend and will be sure to get back to you with what i find. i'll also be trying grady's suggestion...first. if you think of anything else between now and this weekend, please share. yuo've been very informative - thanks very much.
thanks for all this information. i'll not get to this until this weekend and will be sure to get back to you with what i find. i'll also be trying grady's suggestion...first. if you think of anything else between now and this weekend, please share. yuo've been very informative - thanks very much.
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results
hvac-emt,
well i took a different tack in hopes of finding something before dis-assmbling anything. on the advice of a friend, i closed all the other valves in the system. two would not close, so i went with three radiators open. he mentioned that it would be a good way to isolate the radiator to be absoluely sure it would not take steam. i cranked up the heat and what happens is this - the steam enters the radiator but stays along the bottom middle pipe. it makes its way across the bottom of the radiator and up to the vent, thereby heating/closing off the vent before the radiator can heat up. the rest of the radiator stayed dead cold except for the very bottom center cross-section. am i making sense? does this sound like anything you've seen?
well i took a different tack in hopes of finding something before dis-assmbling anything. on the advice of a friend, i closed all the other valves in the system. two would not close, so i went with three radiators open. he mentioned that it would be a good way to isolate the radiator to be absoluely sure it would not take steam. i cranked up the heat and what happens is this - the steam enters the radiator but stays along the bottom middle pipe. it makes its way across the bottom of the radiator and up to the vent, thereby heating/closing off the vent before the radiator can heat up. the rest of the radiator stayed dead cold except for the very bottom center cross-section. am i making sense? does this sound like anything you've seen?
#17
Something isn't quite adding up. My initial suggestion would be, take the valve apart and see it everything is in tact. If it is, which sounds likely, close it and disconnect the radiator from the valve at the union. Then move it slightly and look into it with a flashlight. Each piece of information gained is like a fork in the road. If the valve is damaged inside, remove the disc and make sure there is no other debris inside and try the system again. Part of what you say sounds like steam is traveling at a high velocity through the radiator. That could be caused by some sort of restriction. If the valve is functional, you can remove the radiator and not have a problem with heat in the rest of the house. If you remove the radiator, you can open the valve carefully with the outlet pointed into a bucket and see if you get a full flow or just a dribble of steam. Post back with any new information.
Ken
Ken
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valve
KField,
thanks for this and it piggy-backs onto what hvac-emt has indicated. you both suspect something with the valve. i'll follow the experts and post back. weekends offer me the only opportunity, though, so i'll be a while getting back to you. many thanks.
thanks for this and it piggy-backs onto what hvac-emt has indicated. you both suspect something with the valve. i'll follow the experts and post back. weekends offer me the only opportunity, though, so i'll be a while getting back to you. many thanks.