Leak In Radiator

Jeanne S.

Hello,

I have a steam system and the radiator on the top floor of my house is leaking, not from the vent but from the part where you shut the radiator on and off. It leaks quite a bit in cold weather like this and then when its not too cold, it does not do it at all. The water comes from right where you turn the knob down to shut the radiator off. Does anyone know what would cause this and how to fix it? Thank you for any help you can offer. Jeanne

Jeanne S.

Leak In Radiator

Hello,

I have a steam system and the radiator on the top floor of my house is leaking, not from the vent but from the part where you shut the radiator on and off. It leaks quite a bit in cold weather like this and then when its not too cold, it does not do it at all. The water comes from right where you turn the knob down to shut the radiator off. Does anyone know what would cause this and how to fix it? Thank you for any help you can offer. Jeanne

Adam Jones

Radiators also leaking . . .

I have a similar problem, but two of my radiators are leaking around the nut that joins the radiator to the supply valve. We just bought our house last summer and moved in after a few months of remodeling, so this is our first winter in a house with steam heat (one-pipe). We disconnected the three radiators on the main floor of our two-storey house last summer to refinish the floors, and two of them have leaked to varying degrees ever since. One of the radiators appears to have leaked even before we disconnect/reconnected it because we had to replace some rotten floor boards under it when we refinished the floors. I purchased a better pipe wrench and tightened the nuts down more, and this seemed to stop the leaking for a while. I have also wrapped my pipes with fiberglass insulation--we had the asbestos removed during the remodeling--as Dan recommends to help keep my steam "dry."
Now that the weather has gotten down into the single digits and teens these past few weeks, the leaking has really gotten worse. I'm assuming that's just because the boiler is coming on more often and producing more steam and thus more condensate. Is this a result of parts wearing down and not fitting as tightly any more? Or should I have put some putty or sealant in the joint when I connected the radiator to the supply valve? Any recommendations would be greatly appreciated.

Adam

Adam Jones

Radiators also leaking . . .

I have a similar problem, but two of my radiators are leaking around the nut that joins the radiator to the supply valve. We just bought our house last summer and moved in after a few months of remodeling, so this is our first winter in a house with steam heat (one-pipe). We disconnected the three radiators on the main floor of our two-storey house last summer to refinish the floors, and two of them have leaked to varying degrees ever since. One of the radiators appears to have leaked even before we disconnect/reconnected it because we had to replace some rotten floor boards under it when we refinished the floors. I purchased a better pipe wrench and tightened the nuts down more, and this seemed to stop the leaking for a while. I have also wrapped my pipes with fiberglass insulation--we had the asbestos removed during the remodeling--as Dan recommends to help keep my steam "dry."
Now that the weather has gotten down into the single digits and teens these past few weeks, the leaking has really gotten worse. I'm assuming that's just because the boiler is coming on more often and producing more steam and thus more condensate. Is this a result of parts wearing down and not fitting as tightly any more? Or should I have put some putty or sealant in the joint when I connected the radiator to the supply valve? Any recommendations would be greatly appreciated.

Adam

Mike T., Swampeast MO

Jeanne

Your leak is likely very easy to fix. First tighten down the smaller nut you see at the top slightly. The shaft connecting to the handle passes through this nut. Everything is brass and brass is relatively soft so tighten but use no more than a 12' long wrench and don't use extreme force. If this doesn't stop the leak the packing inside has failed. This is a simple fix just like the packing in an older water faucet. Since it's steam you don't have to worry about draining the system--just ensure it is off.

A bit of tightening of that packing nut will likely solve the problem. If not and you're not comfortable replacing the packing any reasonably handy person or plumber can do it.

Dave DeFord

Your problem seems to be..

a leaking stem seal. A couple of causes are possible. 1. The nut below the handle that the stem (the round thing) goes through migh be loose. Try tightening it with a wrench or if absolutely necessary a pair of pliers or channel-locks. Don't get it too tight just real snug.
2. The other problem may be that the packing under the packing nut is worn out. This is usually something called rope or string packing which looks like a piece of thick string with pencil lead on it. You can get this at your local hardware store or plumbing supply house - I personally try to avoid the "Big Box" stores although they may carry it too. You install this buy removing the knob. removing the packing nut (disussed above) removing the old packing and installing the new packing. Wind the new packing around the stem until it's a little bit higher than the top of the threads then reinstall the packing nut to compress the packing. Again don't tighten this too tight just enough to stop any leaking then maybe 1/4 to 1/2 turn more. Not too difficult just be carful not to break anything by overtightening.

Mike T., Swampeast MO

Adam

Your leak is at the union connection. Unions almost always seal solely with metal-to-metal contact. They must be CLEAN and reasonably aligned to seal.

Again yours is a steam system so you can work without draining--just ensure the boiler is OFF! Do though put rags underneath as a bit of really nasty water will probably come out when you open!

If you've already tightened the union and it still leaks, it is likely dirty or the mating surfaces have been damaged. Open the joint, clean everything VERY well, and reassemble. Again this is brass so you don't want to use too much force--a 12" pipe wrench is sufficient unless the union is REALLY large. Unions can be damanged by overtightening so be careful.

If it still leaks, the union is likely damaged. Sometimes you can get by with a non-hardening teflon-containing pipe dope on the union threads and a bit on the mating surfaces but remember with steam that you MUST work CLEAN and you don't want the pipe dope getting into the piping itself.

If you try some pipe dope and it still won't stop leaking the valve will need to be replaced. You WILL need pipe wrenches in PAIRS for this operation--one on the valve and one on the pipe. Most likely the tailpiece (the other ½ of the union) will have to be replaced as well. These are often impossible to remove from the old bushing so it has to be removed also--this takes a BIG wrench. When buying replacement steam radiator valves (I seriously doubt you can find or order them at "home centers") make certain you specify STEAM valves as they are different than water valves. You can use a steam valve on a water system but not vice-versa.

Tony Brown

Mine leaks too

Mine leak @ the union. Could I have damaged something? My 3 radiators in particular didn't have enough pitch (I thought) so I wedged some wood splints below the vent end of the radiator. Had a heard time tilting the radiators and was hoping I didn't damage anything while "forcing" the tilt. Could it be?