Cold Radiator

[IanW]

Just had a kitchen fitted and builders had to drain the oil fired boiler to move pipework. When it was filled up again i was left with one cold radiator.
When all the others are shut off, the problem one will get hot so there is a flow to it. I have been bleeding them with no success. Is there a sequence I should follow when trying to bleed them
The builders assured me that this had nothing to do with what they did.
Well they would do.

 

[MANDATE]

It could be there was an air lock in the pipe work and by closing off the hot radiators the pump has pushed the air along where it will rise either up the overflow pipe or into the other radiators if they are on.
As each radiator gets a share of the hot water they all get a share of the air, so I would open and bleed each satisfactory radiator in turn at intervals making sure the faulty one is still OK.
You may find as water containing air is circulated then small pockets of air will form in the radiators and you will have to bleed them again say the following day.

 

[oilman]

There is a possibility that some debris has been moved by draining and could be restricting some pipes, if you have a drain cock under this radiator, it would be worth seeing if the water comes out black at first as this will indicate there is debris in the system.

opening the lockshield valve may help, and if it's fully open, check and see if the others are fully open too. If they are the system needs balancing.

 

[IanW]

Thankyou Gentlemen I shall have another go at it tomorrow.

Ian

 

[IanW]

A big thankyou mandate.
I shut all rads off & first one I opened to bleed let all the air out.
All are nice & hot now
Happy new year to all.
Ian