Hi Guys,
I have been redecorating one of our upstairs bedrooms and have had to replace the Rad valves in this room as they were corroded and would not lock off to remove the rad.
I drained the system down from a downstairs rad in the dining room as this was the only place I could get a bucket under the pipe. There was no drain off valve anywhere so whilst I had the system drained I decided to fit a drain to the rad in the living room. This rad is the nearest to the patio doors and best place to fit the drain.
I did find that this rad had not emptied and was still full of water despite draining the system from the dining room. So, I drained this rad from the valve into a bowl then fitted the drain, fitted the new rad valves upstairs and and re-pressurized the system (it is a combi boiler). I then bled all the rads, topped up the pressure and fired up the system. All rads got hot apart from the one that I fitted the drain to. So I concluded there was an airlock.
To fix this I locked of all rads apart from the cold one and fired up the system. There is a load of gurgling and the rad gets hot. I open all other rads and the system is fine with all rads staying hot. I have bled a lot of air out of one of the upstairs rads (about half the rad).
When the system fires up the following day the same rad with the drain is cold and wont start until I lock off all other rads to bring it to life. Does anyone have any ideas what could be causing this and how to fix it? Is it worth re draining the system and running some cleaner through it to stry and clear any sludge build up? I am wondering if there is a build up that needs some higher pressure to shift and get things going, but once it is circulating water it is fine until it cuts out and the sludge settles?
Thanks
Rich
I have been redecorating one of our upstairs bedrooms and have had to replace the Rad valves in this room as they were corroded and would not lock off to remove the rad.
I drained the system down from a downstairs rad in the dining room as this was the only place I could get a bucket under the pipe. There was no drain off valve anywhere so whilst I had the system drained I decided to fit a drain to the rad in the living room. This rad is the nearest to the patio doors and best place to fit the drain.
I did find that this rad had not emptied and was still full of water despite draining the system from the dining room. So, I drained this rad from the valve into a bowl then fitted the drain, fitted the new rad valves upstairs and and re-pressurized the system (it is a combi boiler). I then bled all the rads, topped up the pressure and fired up the system. All rads got hot apart from the one that I fitted the drain to. So I concluded there was an airlock.
To fix this I locked of all rads apart from the cold one and fired up the system. There is a load of gurgling and the rad gets hot. I open all other rads and the system is fine with all rads staying hot. I have bled a lot of air out of one of the upstairs rads (about half the rad).
When the system fires up the following day the same rad with the drain is cold and wont start until I lock off all other rads to bring it to life. Does anyone have any ideas what could be causing this and how to fix it? Is it worth re draining the system and running some cleaner through it to stry and clear any sludge build up? I am wondering if there is a build up that needs some higher pressure to shift and get things going, but once it is circulating water it is fine until it cuts out and the sludge settles?
Thanks
Rich