Another 1 Radiator not working

[Daze190]

You may be bored with this but i have read through all the answers and i'm still stuck

My house is about 16 years old and i had my boiler changed about 8 years ago to a Worcester Bosch 24i junior combi.
A couple of years ago i had a kitchen extension so the radiator was moved 6 feet into the new bit, since then that radiator has got worse and worse until it stopped altogether ! So thinking that it was blocked with sludge i decided to buy a new rad and move it through into the conservatory so after connecting everything up and refilling the system i fired up the boiler bled all the rads but the new one doesn't get hot ! even the pipes are cold.
I have tried turning all the other rads off but nothing the boiler just turns off !! If i bleed all the water out of the rad so the hot water has to come through it gets warm around the valve but when i stop bleeding it goes cold again
Please help...

 

[petertheplumber12]

when all the other rads are turned off set the thermostat on boiler to the lowest temp while still on. You should be able to get the water to flow into radiator by turning both valves off, removing one from rad and catch any water from rad. Then open 1 rad valve and keep the pressure on the boiler at about 1.5bar that should push the air out and water thro, then repeat for valve on other end of rad. use valve not bleed nipple. Much easier with 2 people 1 at boiler pressurising the other at rad collect water and controlling valve. Wet and dry vac from Wicks or wherever is the easiest way.

 

[Daze190]

Hi Peter, thanks for the info i just tried it and it worked for a while but as soon i connected the second valve the flow stopped and the radiator went cold again

 

[petertheplumber12]

do you do the same procedure for both valves, and of course you will need to bleed the rad of air when re-connected, and make sure both valves are fully open.

 

[Daze190]

yep yep and yep

 

[petertheplumber12]

If the water is flowing freely from each valve and there is now obvious air lock then there must a blockage. With only one rad with valves open there is no other answer, although air lock can be very difficult to remove sometimes but not I would have thought with a combi. If you have a wet and dry vac, remove the nut that has the bleed valve in it, with both rad valves off of course, then open a valve and see how well water flows without air spurting, 1st 1 valve then the other. keep the filling loop going at the same time. Empty the vac of water between 1 valve and the other, If that doesn't work with just 1 rad open then i am running out of ideas. Unless of course you have mixed up the pipework, if it runs as a 1 pipe system instead of 2 pipe or the pipes don't connect as 1 for flow and the other for return.

 

[Daze190]

Should water come out of both valves ? The left hand valve runs hot when disconnected and will fill the rad but the right hand valve does nothing ?

 

[petertheplumber12]

then make sure left one is closed and only right on is open then do the test the filling loop fills both sides of system flow and return so as long as both isolating valves are open on the boiler the pressure filling should go to the right side valve and start flowing, or there is a blockage. Make sure you run the water for st least 5 minutes. as long as the boiler pressure gauge doesn't increase in pressure the water must be filling pipe. If pressure goes up on boiler there is a blockage or faulty pipework.

 

[hazetimesfive]

what kind of valve on the RH. can u see inside and see thats its actually open?

 

[Daze190]

ok so how do i test if the filling loop fills both sides of system flow and return and how do i check that both isolating valves are open on the boiler ?

 

[Daze190]

what kind of valve on the RH. can u see inside and see thats its actually open?

Its a normal valve ! i thought the same thing so i disconnected the pipe in and could open and close the valve stopping the rad draining and emptying when open.

 

[Daze190]

Don't know if it helps but i connected a flexi to the rh valve (which i presume is the return ) and tried to blow down it but couldn't ! so if i couldn't blow water down it how can the heating pump move it round ??

 

[petertheplumber12]

Kinked or a blockage, get rid of flexible pipe they kink easily when hot if not straight.

 

[Daze190]

Not good ! could it be anything else before i have to start ripping walls apart

 

[petertheplumber12]

sorry for delay have been out this evening, flow /return doesn't matter if 1 pipe is not flowing rad will stay cold. you have no choice it must be the flex pipe that is the cause, also the standard flex pipe has a bore of about 10mm not 15mm do what ever you have to do to remove it. and do it properly. If you have a wife or partner pretend it was not your fault. javascript:emoticon('')javascript:emoticon('')