Unit Operation
52
•
Pretrip tests are allowed with some Check and Log alarms
present.
Pretrip Test Sequence
Pretrip tests proceed in the order shown below.
Full Pretrip Test
Full Pretrip Tests include all of the tests shown below.
•
Amp Checks - Each electrical control component is
energized and the current drawn is confirmed as within
specification.
•
Engine Start - The Engine will start automatically.
•
Defrost - If the coil temperature is below 45 F (7 C), a
defrost cycle is initiated.
•
RPM Check - The engine RPM in high and low speed is
checked during the Cool Check.
•
Cool Check - The ability of the unit to cool in low speed is
checked.
•
Heat Check - The ability of the unit to heat in low speed is
checked.
•
Report Test Results - The test results are reported when the
Pretrip Test is completed. If the Pretrip Test fails, alarm
codes will exist to direct the technician to the source of the
problem.
Engine Running Pretrip Test
Engine Running Pretrip Tests include all of the tests shown
below. They do not include the Amps Check or the Engine
Start tests.
•
Defrost - If the coil temperature is below 45 F (7 C), a
defrost cycle is initiated.
•
RPM Check - The engine RPM in high and low speed is
checked during the Cool Check.
•
Cool Check - The ability of the unit to cool in low speed is
checked.
•
Heat Check - The ability of the unit to heat in low speed is
checked.
•
Report Test Results - The test results are reported when the
Pretrip Test is completed. If the Pretrip Test fails, alarm
codes will exist to direct the technician to the source of the
problem.