another plumbing problem

[BaconBoy]

we have a coal fired central heating system,hot water tank is in the loft,use either the emersion heater or the coal fire for the hot water.

we had 3 rads downstairs and 4 upstairs,all these warmed up nicely when we last had the heating on(last winter)

the pump is in the wall by the fire.

we have recently redecorated the living room and removed the rad.the pipes have been joined with a 'c' shaped joint

now we have a problem with the rad in the hallway(the nearest rad to the living room rad that was removed),the hallway rad doesn't heat up(there is water in the rad) but all the other rads in the house are ok including the other downstairs rad in the kitchen.

I have bled the remaining rads and there doesn't seem to be any more air left.

the sytem was drained off via the hallway rad when the work was done.

the living room rad would of been the furthest rad from the tank

any ideas what the problem is please,and any advice will be greatly appreciated.

thanks

ps not a plumber so could you explain things in dumb-*** terms please

[Doggone]

The piece of pipe you replaced the lounge rad with will need the air bleeding out of it. Andy

[NitroJoe]

Get your heating running, turn off all the other rads on one side by the thermostat or lockshield (whichever you have) That should hopefully push any air lock out of the problem area, when the problem rad is hot (instant I expect) you can turn on your other rads and check for air in the system again. If you still have problems you will need to balance the rads

 

HTH,

Joe

Edited November 3, 2013 by NitroJoe

[BaconBoy]

The piece of pipe you replaced the lounge rad with will need the air bleeding out of it. Andy

have done as you have said joe and the rad is still not hot but the new 'joint' IS now hot,so I be thinking there must be an air block between the new joint and the cold hallway rad do I just wait a while and hope the block gets pushed to the hallway rad or is there anything else I can do?

thanks

[SEshooter]

Was the system water sludgey when drained? If it was drained via the rad that is not working it could be sludged up preventing circulation. If this is the case,isolate both rad valves, remove the air vent from rad( if it's a permo rad) you will need a 1/2" male copper to iron and a short piece of 15mm copper. Make the copper to iron in to the rad where you removed the air vent and make the 15mm tube in to the copper to iron. Connect a hose to the 15mm tube and other end of hose in a drain. Open valves one at a time until water runs clear and there is no air. Isolate valves make vent back in and turn on rad. This should be done with heating turned off. Hope this helps

[Del T]

Has it got a thermostat on the rad? Sometimes the pins stick.

[Yellow Bear]

have done as you have said joe and the rad is still not hot but the new 'joint' IS now hot,so I be thinking there must be an air block between the new joint and the cold hallway rad do I just wait a while and hope the block gets pushed to the hallway rad or is there anything else I can do?

thanks

Have you left valves on the C shaped pipe - if not it is likely that the water (all fluids being lazy b*******) is taking the route of least resistance through the link pipe - If you have valves on it shut one down and open a quarter to half turn. In other words "balance" the system .

 

D

[BaconBoy]

Was the system water sludgey when drained? If it was drained via the rad that is not working it could be sludged up preventing circulation. If this is the case,isolate both rad valves, remove the air vent from rad( if it's a permo rad) you will need a 1/2" male copper to iron and a short piece of 15mm copper. Make the copper to iron in to the rad where you removed the air vent and make the 15mm tube in to the copper to iron. Connect a hose to the 15mm tube and other end of hose in a drain. Open valves one at a time until water runs clear and there is no air. Isolate valves make vent back in and turn on rad. This should be done with heating turned off. Hope this helps

system was drained via the bad rad and the water ran clear.

Has it got a thermostat on the rad? Sometimes the pins stick.

all thermostats seem to be working ok.hot/cold

[BaconBoy]

Have you left valves on the C shaped pipe - if not it is likely that the water (all fluids being lazy ********) is taking the route of least resistance through the link pipe - If you have valves on it shut one down and open a quarter to half turn. In other words "balance" the system .

 

D

there isn't any valves on the c shape(it's only a small 'joint')

It was made as small as possible so it can be pushed back into the pipe boxing on the wall

it is 1 90' bend then a tiny piece of pipe(1"long)then another 90' back into the old piping.

[TIGHTCHOKE]

Air lock!

[Yellow Bear]

there isn't any valves on the c shape(it's only a small 'joint')

It was made as small as possible so it can be pushed back into the pipe boxing on the wall

it is 1 90' bend then a tiny piece of pipe(1"long)then another 90' back into the old piping.

I would suggest that is where the problem lies - if the loop gets smoking hot it is unlikely to be air locked so unless it is a continuous loop single pipe system water is "short circuiting" in that section via the least line of resistance. Can't think of a simple solution to see if this is the case other than "freezing" the loop with a cheap freezer kit to see if that solves the problem. If it does I would suggest replacing the loop with 2 blank caps.

 

D

[NitroJoe]

Has it got a thermostat on the rad? Sometimes the pins stick.

 

Good point, try taking the head off thermostat on the offending radiator and see if the little pin will move in and out.. If not, give it a little persuasion!

[Tim Kelly]

 

Good point, try taking the head off thermostat on the offending radiator and see if the little pin will move in and out.. If not, give it a little persuasion!

 

X2

[BaconBoy]

thanks for the help guys,keep it coming

ok so the hot water is all the way to the shut off valve on the bad rad.i have opened and closed this valve many times but the hot water doesn't go any further

Aaaaaaaaaaaaaaaaaaahhhhhhhhhhhhhhhhhhhhhh

[-Mongrel-]

I would suggest that is where the problem lies - if the loop gets smoking hot it is unlikely to be air locked so unless it is a continuous loop single pipe system water is "short circuiting" in that section via the least line of resistance. Can't think of a simple solution to see if this is the case other than "freezing" the loop with a cheap freezer kit to see if that solves the problem. If it does I would suggest replacing the loop with 2 blank caps.

 

 

The fact that one 'old rad loop' is stopping the flow to the next rad would suggest this could well be an old one pipe system.

[seph234]

If it was me I would drain the system again and make alterations to the pipework where your rad was taken out to incorporate some sort of restriction so that it can't short circuit a simple gate valve or something all singing its up to you, and whilst drained i would take the rad that is not getting hot, off and flush out with a hose pipe and replace the rad valves on that radiator reconnect, refill bleed and see if all is good.

Edited November 3, 2013 by seph234

[bruno22rf]

I would, like mentioned already, check that the pin on the TRV is moving-spray it with WD40 and then push it downwards with your thumb on the back of a spoon-push it down then pull it back up several times (pliers) then see what happens.

[LondonLuke]

thanks for the help guys,keep it coming

ok so the hot water is all the way to the shut off valve on the bad rad.i have opened and closed this valve many times but the hot water doesn't go any further

Aaaaaaaaaaaaaaaaaaahhhhhhhhhhhhhhhhhhhhhh

Define open and closed this valve?

 

It may be the seat is stuck or the TRV pin is stuck

 

If the latter go very carefully when lifting the pin. Remove head and tap the area in the first instance.

[vampire]

Connect a hose to the drain off cock/valve on the hall rad,turn boiler off and drain some water out,you should hear the air moving and once it stops making the noise just close the cock/valve.

Sorted.Air lock.

Edited November 3, 2013 by vampire

[BaconBoy]

right lads,i think I,sorry we might of sorted it.

have been messing around for the last hour balancing the system and the bad rad is beginning to get warm.

hopefully it might be sorted now.

a big thanks to everyone for there help

please send any invoices to my accountant at www.nigerianplumbingservices@notacatinhellschanceofgettingpaid.com

thanks again lads

[seph234]

I hope its all sorted for you.

[Del T]

Glad its sorted. Now balance the system , rads nearest the heat source can just be cracked open half a turn on the lockshield and the further ones away can be opened more.

 

Invoice in the post lol

[SEshooter]

Glad it's sorted. You use the same accountant as me, I'll give him the bill next time I'm there