DIYnot
Local | Network
   DIYnot > Forums
Local | Network
DIYnot Network Local DIYnot Network Local  
  Forum IndexForum Index     RulesRules    HelpHelp     Join FREERegister Free     About CookiesCookies     SearchSearch     LoginLogin 

Emptying cemtral heating tank

Goto page 1, 2  Next
 
Post new topic   Reply to topic    DIYnot.com Forum Index > Plumbing and Central Heating
Search this topic :: View previous topic :: View next topic  
Author Message
camerart

from United Kingdom

Joined: 19 Nov 2008
Posts: 194
Location: Dorset,
United Kingdom
Thanked: 1 time

PostPosted: Thu Apr 05, 2012 10:30 am Reply with quote

Hi,

I'm moving a radiator, and need to empty the pipework.

I've locked the ballcock up in the small tank (Central heating) this feeds the coil inside the hot water tank, and no valves.

First I closed all of the other radiator valves, then I emptied the pipework at each end of the old radiator. Checked the tank and it's still full. Shouldn't it have emptied?

Cheers, Camerart.
Back to top
 Alert Moderators

If you do not want to see this advert, click here to login or if you are new click here to join free.
SimonH2

from United Kingdom

Joined: 04 Nov 2010
Posts: 2886
Location: Cumbria,
United Kingdom
Thanked: 319 times

PostPosted: Thu Apr 05, 2012 7:15 pm Reply with quote

This really belongs in Plumbing ...

From what you describe I'd expect the F&E (Feed and Expansion) tank to be empty. Did you leave the valve open on the rad you are moving ? If not then you'll have drained the rad but not the pipework.
Back to top
 Alert Moderators
camerart

from United Kingdom

Joined: 19 Nov 2008
Posts: 194
Location: Dorset,
United Kingdom
Thanked: 1 time

PostPosted: Thu Apr 05, 2012 8:43 pm Reply with quote

Ok, I'll move it to plumbing, thanks.
Back to top
 Alert Moderators
JohnD

from United Kingdom

Joined: 15 Nov 2005
Posts: 36331
Location: Hampshire,
United Kingdom
Thanked: 1298 times

PostPosted: Thu Apr 05, 2012 9:23 pm Reply with quote

how much water came out of the valves at the ends of the old rad when you opened them after removing the radiator?
Back to top
 Alert Moderators
camerart

from United Kingdom

Joined: 19 Nov 2008
Posts: 194
Location: Dorset,
United Kingdom
Thanked: 1 time

PostPosted: Thu Apr 05, 2012 9:40 pm Reply with quote

JohnD wrote:
how much water came out of the valves at the ends of the old rad when you opened them after removing the radiator?


About a 1/2 gallon.
Back to top
 Alert Moderators
JohnD

from United Kingdom

Joined: 15 Nov 2005
Posts: 36331
Location: Hampshire,
United Kingdom
Thanked: 1298 times

PostPosted: Thu Apr 05, 2012 9:55 pm Reply with quote

do the pipes to the rads come down from the ceiling?

when you look in the feed & expansion tank, how deep is the mud in the bottom, and what colour is the water?

do you know when it last had inhibitor or cleaner added?
Back to top
 Alert Moderators
camerart

from United Kingdom

Joined: 19 Nov 2008
Posts: 194
Location: Dorset,
United Kingdom
Thanked: 1 time

PostPosted: Thu Apr 05, 2012 10:09 pm Reply with quote

JohnD wrote:
do the pipes to the rads come down from the ceiling?

when you look in the feed & expansion tank, how deep is the mud in the bottom, and what colour is the water?

do you know when it last had inhibitor or cleaner added?


The pipes come along the hall ground floor, from boiler ground floor.

The tank had about 3 gallons in it, with a brown covering of sludge about 1" on the bottom. I syphoned it out, then put cleaner in. Then I noticed the outlet is 5inches up, so the chemical is still in there. I have inhibitor for later. I doubt it has had inhibitor in for 30 years, if any. When I drained the water, it was black.
Back to top
 Alert Moderators
JohnD

from United Kingdom

Joined: 15 Nov 2005
Posts: 36331
Location: Hampshire,
United Kingdom
Thanked: 1298 times

PostPosted: Fri Apr 06, 2012 7:18 am Reply with quote

it is very possible that there is now a blockage in the feed and expansion pipe. Most usually it is where the 15mm joins onto the large circulating pipes. If you hold a magnet against this T-joint, is it attracted? If so it will be the black iron oxide sediment. Unless it is a compression joint that you can undo, you will have to cut out and replace the blocked section.
Back to top
The following user says thank you to JohnD for this useful post:
bookerc (7 Apr 2012)
 Alert Moderators
camerart

from United Kingdom

Joined: 19 Nov 2008
Posts: 194
Location: Dorset,
United Kingdom
Thanked: 1 time

PostPosted: Fri Apr 06, 2012 8:09 am Reply with quote

WOW! I bet you are correct. When I was syphoning the tank, the syphon kept blocking. There's a compression joint handy, on the silver downpipe, which might give you an idea of it's age. I predict a soaking in dirty water this morning.

Thanks JohnD, I would have never guessed.
Back to top
 Alert Moderators
45yearsagasman

from United Kingdom

Joined: 14 Mar 2010
Posts: 4790
Location: Norfolk,
United Kingdom
Thanked: 808 times

PostPosted: Fri Apr 06, 2012 8:54 am Reply with quote

Login to view this image
If it has blocked in this area, block off the cold feed outlet in the exp tank before you start cutting the cold feed, and have some towels to hand.
Back to top
 Alert Moderators
camerart

from United Kingdom

Joined: 19 Nov 2008
Posts: 194
Location: Dorset,
United Kingdom
Thanked: 1 time

PostPosted: Fri Apr 06, 2012 9:10 am Reply with quote

45yearsagasman wrote:
Login to view this image
If it has blocked in this area, block off the cold feed outlet in the exp tank before you start cutting the cold feed, and have some towels to hand.


OK. I just did JohnD's check with a magnet, and it's not magnetic till I get to the 28mm, which I think must be steel pipe, as it's magnetic all along. I'm just off to attack it.

Thanks.
Back to top
 Alert Moderators
camerart

from United Kingdom

Joined: 19 Nov 2008
Posts: 194
Location: Dorset,
United Kingdom
Thanked: 1 time

PostPosted: Fri Apr 06, 2012 3:36 pm Reply with quote

First I scooped the chemical cleaner out out the expansion tank. Then tried to loosen one side of the compression fitting at 15mm to 28. It moved a little, then I realised I wasn't going to be able to tighten it as there is no room.

The outlet of the Expansion tank is 4 inches up, and there is a little extra thread poking out from the seal, so I soldered a length of 15mm to a fitting, screwed it onto the outlet, and made a little pump. Violent pumping and the blockage cleared. Then I added some garden hose to syphon it from the bucket.

All working, again with a new rad in the kitchen.

JohnD's prediction that there might be a leak was correct, and my prediction that I will get soaked was also correct, so happy days.

Thanks all, Camerart.
Back to top
 Alert Moderators
JohnD

from United Kingdom

Joined: 15 Nov 2005
Posts: 36331
Location: Hampshire,
United Kingdom
Thanked: 1298 times

PostPosted: Fri Apr 06, 2012 3:47 pm Reply with quote

time to use your cleaning chemical soon! icon_razz.gif

I like your pump idea.
Back to top
The following user says thank you to JohnD for this useful post:
camerart (8 Apr 2012)
 Alert Moderators
camerart

from United Kingdom

Joined: 19 Nov 2008
Posts: 194
Location: Dorset,
United Kingdom
Thanked: 1 time

PostPosted: Fri Apr 06, 2012 4:56 pm Reply with quote

JohnD wrote:
time to use your cleaning chemical soon! icon_razz.gif

I like your pump idea.


I left it in the tank 'for next time!'

I didn't explain well. I scooped the chemical into a bucket, pumped the blockage clear, then attached a hose to the pump pipe and syphoned the chemical into the system.

It could have been diluted though with all the messing about, will it still work?

In hindsight, I think I should have finished the job, then emptied the water out of the Kitchen radiator, and poured the chemical into one of the top plugs.
Back to top
 Alert Moderators
camerart

from United Kingdom

Joined: 19 Nov 2008
Posts: 194
Location: Dorset,
United Kingdom
Thanked: 1 time

PostPosted: Fri Apr 06, 2012 4:57 pm Reply with quote

JohnD wrote:
time to use your cleaning chemical soon! icon_razz.gif

I like your pump idea.


I left it in the tank 'for next time!'

I didn't explain well. I scooped the chemical into a bucket, pumped the blockage clear, then attached a hose to the pump pipe and syphoned the chemical into the system.

It could have been diluted though with all the messing about, will it still work?

In hindsight, I think I should have finished the job, then emptied the water out of the Kitchen radiator, and poured the chemical into one of the top plugs.

Thanks for your help.
Back to top
 Alert Moderators
Search this topic :: View previous topic :: View next topic  
Post new topic   Reply to topic    DIYnot.com Forum Index > Plumbing and Central Heating All times are GMT
Goto page 1, 2  Next
Page 1 of 2

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
Similar Topics   Replies   Views   Posted 
sealed cemtral heating 17 600 Thu Jul 28, 2011 5:28 pm
Expansion tank not emptying 5 540 Sun Mar 25, 2007 10:11 am
Residue after emptying cold water tank. 4 260 Sun Jul 11, 2010 2:04 pm
COLD WATER EXPANSION TANK NOT EMPTYING 2 180 Wed Sep 15, 2010 7:59 pm
hot water tank emptying 3 140 Mon Jun 13, 2011 11:59 am


 
DIYnot
Find an Expert | Find a Supplier | Search DIYnot.com
Network | Advertising | Newsletter
DIY | DIY How To | @home | DIY Wiki | DIY Forum
By using this site you agree to our Terms of Service / Disclaimer.
Please read our Privacy Policy. Copyright © 2000-2014 DIYnot Limited.