Hi, been having problems with my boiler system. Most likely relates to the radiators not having inhibitor in them for a year - they've now been cleaned and have inhibitor in. Each rad works well in isolation when all others are closed off using the TRV's, so I guess any blockages there are now gone.
The problem now is that the boiler occasionally gets an F23 (water level low) first thing in morning when the timer kicks in, and then gets working after switching off and on again at the mains. However, a constant problem is that the heater will very quickly (about 15 seconds) go from say 34C up to 75C then go into overrun, which just isn't heating enough water up. The rads are just tepid at best. On some occasions the status goes to S.53 (delay mode due to lack of water).
The pressure is at 1.5, the pump speed is set at 100% via D.14, and I've set pump overrun (D.1) to 3 minutes in the hope that more hot water can get pushed round the system. I've also rebalanced the rads by setting the upstairs TRV's to 3, and downstairs to 4 except for the 2 downstairs rads which stay cold unless I direct all flow through them. I've also unscrewed the pumps centre screw slightly and seen a slight dribble, no obvious sound of air.
Any help would be much appreciated.
The problem now is that the boiler occasionally gets an F23 (water level low) first thing in morning when the timer kicks in, and then gets working after switching off and on again at the mains. However, a constant problem is that the heater will very quickly (about 15 seconds) go from say 34C up to 75C then go into overrun, which just isn't heating enough water up. The rads are just tepid at best. On some occasions the status goes to S.53 (delay mode due to lack of water).
The pressure is at 1.5, the pump speed is set at 100% via D.14, and I've set pump overrun (D.1) to 3 minutes in the hope that more hot water can get pushed round the system. I've also rebalanced the rads by setting the upstairs TRV's to 3, and downstairs to 4 except for the 2 downstairs rads which stay cold unless I direct all flow through them. I've also unscrewed the pumps centre screw slightly and seen a slight dribble, no obvious sound of air.
Any help would be much appreciated.