by jmdunman »
Fri Jan 06, 2023 8:50 am
]I've a 20 year old Potterton Suprema 30. The PCB has been changed about 4 times the last in 2017. The system is 3 zones - up heating, down heating and hot water. After turning down the thermostats to 15 for a week then returning them to 20 the boiler now ceases to function properly. It goes through the start up sequence ie call for heat - air proving and ignition - burner on but after 2-3 minutes there is ignition lockout for 2-3 minutes before the whole sequence starts again without intervention by me. The system is correct at 1 Bar pressure. Boiler thermostat is set to 90% of max. The pump seems to be working. Any ideas please. John.
