NATE Light Commercial Refrigeration
What is the MOST important aspect about installing a rooftop package unit? - Answer The roof will
support the weight
What could be at fault of an air cooled system that operates 50°F over ambient temperature? - Answer
An overcharge, air in the system, or air re-circulating over the condenser
Where should the sensing bulb on a TXV be located? - Answer As close to the evaporator as possible on
a horizontal line
When a transformers secondary windings are wired in parallel, it is important to wire them
____________ - Answer In phase with each other
If a single phase compressor is cycling on its overload protector, what should be checked? - Answer
Voltage input, test capacitors, start relays, and motor windings.
What is the maximum pressure drop across an R-404A suction line filter dryer? - Answer 2 PSI (2 degree
saturation temp)
What type of maintenance do water cooled condensers require? - Answer Clean the coil with scale
remover and adjust the water valve
If a CSR motor starts and operates with a high amperage, what could be at fault? - Answer A faulty run
capacitor
