I thought a faulty zone would be a steady led, but I must admit I can't remember, hence asking if it's a fire zone that's tripped.
The only real way to tell is to either find the paperwork that identifies the zones or get a competent person in who can sort it and service it maybe @ the same time.
If your landlord had it fitted they may have the paperwork, and in most cases it's up to them to resolve in any case.