I live in a chalet bungalow. Some years ago when I had a new boiler fitted, the installers draining my cold tank and refilled the system afterwards without any problems.
Three times in the past couple of years I've drained the cold tank myself, twice when I replaced a different tap washer and once for some other reason, I forget what. Each time I've refilled the cold tank, I've somehow created airlocks in the hot water pipes and had to do the recommended trick of connecting the hot and cold feeds to the washing machine and using mains pressure to shift the airlock. But I shouldn't have to do this every time, should I? I'm clearly doing something wrong when I refill.
I've tried various sequences of shutting the taps off upstairs and downstairs during refill but to no avail, the airlock appeared each time. On two occasions I had drained the hot tank at the same time as the cold tank but I can't remember about the third occasion. If I didn't, or if it was only partially drained, I still got the airlock.
So can somebody tell me the correct procedure?
Three times in the past couple of years I've drained the cold tank myself, twice when I replaced a different tap washer and once for some other reason, I forget what. Each time I've refilled the cold tank, I've somehow created airlocks in the hot water pipes and had to do the recommended trick of connecting the hot and cold feeds to the washing machine and using mains pressure to shift the airlock. But I shouldn't have to do this every time, should I? I'm clearly doing something wrong when I refill.
I've tried various sequences of shutting the taps off upstairs and downstairs during refill but to no avail, the airlock appeared each time. On two occasions I had drained the hot tank at the same time as the cold tank but I can't remember about the third occasion. If I didn't, or if it was only partially drained, I still got the airlock.
So can somebody tell me the correct procedure?