Hey all. I've had some builders in doing work and they needed to drain the central heating system. I think they've shut valves on the boiler to do so. I've put the radiators back on and filled them up and bled them. But there's no ch hearing flowing through them. Firstly can you confirm I've put the knobs on the boiler in the correct position? Then any ideas why ch wouldn't be flowing? I've turned all the radiators off except one and ensured that the magnet and radiator are both free of air. I've checked the air release valves in the loft are open. Still nothing. I've set the boiler temperature to max, I don't currently have a working room thermostat, it's a hive one and I don't have internet in the property at the moment. Perhaps that's the issue? The boiler reads that the Ch water is at 78-80° but the pipes are very cold. Any clues to get me going would be great. Thanks.