Describe one sequence
State which fixture was used, how the water behaved and whether the unit eventually started. Approximate timing already noticed is sufficient.
Assess the combination
Incoming flow, sensing and appliance condition may all deserve checks. Keep use stopped if water backs up, and let an engineer assess the installed system rather than bypassing controls.
A useful distinction
A delay after a slow-draining basin and one after a toilet flush may involve different incoming flows. Name the fixture and observed sequence so the enquiry does not reduce every delay to a faulty switch.