clanging, gurgling from recessed convector radiator

SteamedUp

  I have a one pipe steam heating system. Everything seems to function quitely and efficiently except for one radiator (out of 10). This radiator is a recessed cast iron convector. Problems:  We hear a series of clicking, then clanging (almost metalic sounding) right before the hammering sound begins. Soon to follow is a gurgling sound (sounds like the steam is boiling trapped water in the radiator). This gurgling sound actually persists the entire time the radiator is being heated.

  The vents on all the radiators are new (10/2012). I have even replaced the vent on this above mentioned radiator a few days ago and the problem still persists.

  If I could, I would remove this radiator to assess it up and down. Being that it is recessed, it's going to be tricky to get it out of the space (getting a wrench in the tight space below the cast iron frame to loosen the nut is a hard enough task).  

Any thoughts of why this is happening? My guess is that there is trapped water from condensation somewhere in the radiator piping.

Thanks!

 

nicholas bonham-carter

Trapped condensate

Look for anything which may have changed in this radiator, or the system as a whole. Could the pitch of the radiator or its supply pipe have changed because of subsidence?

Check that the inlet valve is completely open. The valve bonnet may be unscrewed to check for a fallen disk which may block the flow of condensate out of the radiator.

Check the pressure of the system as it runs to m.ake sure it is not going above 1.5 psi.--nbc

Jamie Hall

Classic...

water hammer.  Nice to have, once in a while...



Does the clanging and so on start before the radiator begins to get warm?  If so, the problem is not likely to be in the radiator, but in the pipe leading to the radiator or just possibly the valve.  Check the pitch on the pipes leading all the way from the main to the radiator; it's quite possible that somewhere in there there is a "horizontal" section which isn't pitched properly.  Things do sag with age... and the solution is to figure out how to get it pitched right.  Another - though somewhat less likely -- possibility is that the valve isn't fully open (or that it has failed in such a way that the disc, if it is that type, is partly blocking the flow).



If the radiator has already started to get warm when the music starts, then it is more likely to be a valve problem, or just possibly (but a little unusual) the radiator's pitch.  But try the pipes first...

RJ_4

gurgling

Like Nicholas said, you need to look inside the rad. valve.  I had the same symptoms on a job, I found the disk had partially deteriorated and fallen into the valve body  allowing in steam bot not allowing condensate out. I replaced the valve and solved the problem.

STEAM DOCTOR

banging

First thing I would do is to check the boiler water.Look to see if there is a lot of movement in the water glass while the boiler is firing. Most of the banging problems that I have come across are related to dirty/contaminated boiler water. In theory there should be banging in more then one of the radiators if there is a central problem (all the radiators get there steam from the same boiler). However I have found that the excess water will very often find its way to a vulnerable radiator and bang there. Where is this radiator in relation to the boiler? The radiators at the far ends of the house tend to have the most problems. The radiator valve is the last thing that I would touch due to the difficulty involved in accessing these things.

SteamedUp

problem found

Thank you all for the replies. I couldn't take the noises any longer, so we ended up removing the recessed radiator to get a look at whats going on inside. It got to a point that the rad remained cold, as well as the pipes leading up to it.

  These rads do not have an inlet valves. It lloks like the sludge in the rad clogged and filled the internal pipe completely! This is a picture I took. If you look hard, you can see that it is entirely caked with sludge, causing the steam to no longer fill the pipe. I washed it outside with a hose for at least 20 minutes, while dirty water kept coming out. unreal. I can only imagine what all other 9 radiators look like inside. At least the other radiators all heat up though.

   We capped the steam pipe leading to this radiator and the banging has stopped. ahh..peace and quiet. Now I must put everything back together.

SteamedUp

problem found

Thank you all for the replies. I couldn't take the noises any longer, so we ended up removing the recessed radiator to get a look at whats going on inside. It got to a point that the rad remained cold, as well as the pipes leading up to it.   These rads do not have an inlet valves. It lloks like the sludge in the rad clogged and filled the internal pipe completely! This is a picture I took. If you look hard, you can see that it is entirely caked with sludge, causing the steam to no longer fill the pipe. I washed it outside with a hose for at least 20 minutes, while dirty water kept coming out. unreal. I can only imagine what all other 9 radiators look like inside. At least the other radiators all heat up though.    We capped the steam pipe leading to this radiator and the banging has stopped. ahh..peace and quiet. Now I must put everything back together.

SteamedUp

supply pipe

Jamie,

  the clanging all started well before the radiator got warm. Often the rad would not even get warm. I think you are right about the pitch of the supply pipes. Today we will try to correct any sags. I think sludge got stuck somewhere in the supply pipe since the radiator was filled with thick sludge.

SteamedUp

valve

I wish my problem was an easy fix like changing the inlet valve! These recessed radiators do not seem to have inlet valves. They also don;t seem to pitch on their own design. I think the rad was unpitched, causing a great deal of sludge buildup.