Radiator not working

Reply

  #1  
Old 10-27-08, 03:41 PM
O
Member
Thread Starter
Join Date: Oct 2008
Location: Washington DC Suburbs
Posts: 2
Received 0 Votes on 0 Posts
Question Radiator not working

One cast iron radiator out of 11 in my hot water heat system will not get hot. It's full of water, no air, no heat. Any one have suggestions?
 
Sponsored Links
  #2  
Old 10-27-08, 04:17 PM
Grady's Avatar
Forum Topic Moderator
Join Date: Jan 2005
Location: Delaware, The First State
Posts: 14,247
Received 23 Votes on 21 Posts
No Heat, One Radiator

Do you have a good strong flow of water from the bleeder with the circulator on & off?
 
  #3  
Old 10-28-08, 10:49 AM
O
Member
Thread Starter
Join Date: Oct 2008
Location: Washington DC Suburbs
Posts: 2
Received 0 Votes on 0 Posts
Raditor not working

I do have strong water circulation to this raditor when boiler is on or off, but water in this unit is cold, all other raditors in house are hot when heat is on.
 
  #4  
Old 10-29-08, 07:59 PM
I
Member
Join Date: Oct 2008
Location: Toronto
Posts: 70
Received 0 Votes on 0 Posts
Not to highjack yer thread, but I have the exact same issue.
The rad furthest away from the boiler is lukewarm at best while all others are hot. Its the rad in the master bedroom so I need to get this one remedied.
Terry
 
  #5  
Old 10-29-08, 08:04 PM
Grady's Avatar
Forum Topic Moderator
Join Date: Jan 2005
Location: Delaware, The First State
Posts: 14,247
Received 23 Votes on 21 Posts
Bleeding radiator

Something which has worked for me a couple of times is to just bleed & bleed & bleed until you get hot water out of the bleeder. This may take several buckets full. By doing this you can determine from which direction the hot water is coming. If the return pipe gets hot while the supply stays cold, it would seem you have a blockage or restriction somewhere in the supply side. On the other hand if the supply gets hot the problem might be cured by the agressive bleeding or there might be a blockage in the return.
 
  #6  
Old 10-29-08, 08:13 PM
Grady's Avatar
Forum Topic Moderator
Join Date: Jan 2005
Location: Delaware, The First State
Posts: 14,247
Received 23 Votes on 21 Posts
Warm Radiator

Iceracer,
If this is a cast iron radiator, it should have a small bleed valve on the end & near the top of the rad. Most are operated with a special radiator key but some have an exposed square stem or are slotted for a screwdriver. Try bleeding until you get hot water out of the bleeder & get back with us with an update.
 
  #7  
Old 11-24-08, 07:52 AM
S
Member
Join Date: Nov 2008
Location: Toronto
Posts: 1
Received 0 Votes on 0 Posts
One Radiator not working

Similar problem here...

I have a 3 storey 100yrs old house. The boiler (hot water rads) is in the basement as is the circulator (up26-99F Grundfos).

The problem rad is on the 3rd floor, about 25ft almost directly above the boiler. All the pipes I can see have been changed to copper (1.5" I think). All other rads get warm, and I have another rad on the 3rd floor on the other side of the house (~36' horizontal, 25' vertical) that is getting heat... It takes more time to heat this one than 1s or 2nd floor rads, but it warm up nicely, unlike my problem rad.

I have bled all rads, including the problem rad. I had ~12psi in the system, increased water pressure to 15psi (lifting the pressure control valve for a few seconds), but still no change in heat to that problem rad.

The rad has a fairly new stainless steel flow control valve. I tried bleeding a few buckets of water from that rad... Initially, pressure is really good, then after 1/2 bucket (it's a big rad), water pressure dies at the bleeding valve and no water slows down to a few drops per minute. If I close the bleeding valve for 10-15min., I can get another 1/2 bucket at good pressure again before pressure dies.

I checked downstairs and the full bucket of water barely changed the overall system pressure that is still at ~15psi.

When bleeding the bucket full of water, I did notice one connection to the rad get hot (and the first 2 fins became warm -- out of 12 or so fins). This is the connection with no control valve. Is this the intake or outflow of the rad? I think from other rads in the house that the control valve is usually located on the input side... so this would indicate blockage in the feeding pipe for this rad?

All my rads have in/out connections at the bottom of the rad and on the same side, with bleeding valve obviously on the top, at the opposite end of the connections.

It seems like a blockage of some sort on the intake? How can this be fixed? Can I do it without opening the walls or do I need the plumbing and holes all over the place to fix this?

I think the lines go from the basement to a 1st floor rad, then tee off to a second floor rad, and tee off again for this 3rd floor rad...

The whole system was drained many times 3 years ago and the water was somewhat rusty, but the water from bleeding the rads is now fairly clean.

Please help
 
  #8  
Old 11-24-08, 05:52 PM
Grady's Avatar
Forum Topic Moderator
Join Date: Jan 2005
Location: Delaware, The First State
Posts: 14,247
Received 23 Votes on 21 Posts
Third Floor Radiator

The lack of a steady flow of water out of the bleeder tells me the pressure is probably too low. Get it up to 20# & try again.
Pressure rule of thumb: 5# per floor + 4# for the boiler.
 
Reply
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: