No water ?ow can be detected through the controller. De-aeration cycle is started. When water ?ow is detected during this cycle, the de-aeration cycle is terminated and the burner is released. The controller checks the water pressure during static and dynamic situation.
Check the installation for the presence of air;If there is a secondary pump installed and it is not hydraulicly separated, it could cause pressure differences. Check the use of balancing valves.
