I have a Trane CGAEC605AEA1DERM chiller. The unit has sat dormant for several years and now we are starting to try and bring it back on line. It all looks function and my service tech has been able to start it but it only runs for around 2 minutes then shuts down and displays "8A" which it says is the inlet water sensor. Is this what this code actually means? Is there any way of verifying that this is the problem that is shutting the unit down?