A customer purchasing a Hot-swap for Calibration is, in good faith, returning an engine that is operational and younger than 6 years.
A customer with a failed (broken, not-operating) engine cannot use the Hot-swap for Calibration service. They have the option to purchase a new engine.
If a returned engine cannot be refurbished, it is considered to be a failed engine and the customer will need to pay the Hot-swap for Failure surcharge (the difference between the cost of the two services).
A failed engine is considered when one of the following is true:
no-data can be produced,
the profiler red light is activated,
the engine is physically older than 6 years
the station has not been maintained (filters, etc) within the last 3 years (i.e. neglect)
Hot-swaps for Calibration cannot be sold to pre-paid customers however they can purchase Hot-swap for Failures.