Keeprite Refrigiration Condensing Unit KMS150L6

Enter the compressor discharge pressure

Enter the compressor suction pressure

Is the liquid line sight glass clear and expansion valve operating correctly?

Enter the oil level in the compressor sight glass

Is the thermostatic expansion valve set for proper superheat?

Enter the voltage reading at the compressor terminals

Enter the amperage reading at the compressor terminals

Is the high pressure control setting correct?

Measure the suction pressure at the bulb location using a gauge in the external equalizer line or directly in the suction line.

Measure the temperature of the suction line at the thermostatic expansion valve bulb location.

Temperature Conversion and Calculation

Convert the measured suction pressure to a saturated evaporator temperature using a Pressure-Temperature chart.

Subtract the saturated temperature from the actual suction line temperature to determine the superheat.

Is the superheat within the recommended range for the system's design TD?

Ensure all connections are tight

Check compressor crankcase oil level (if equipped with sight glass)

Verify compressor components are properly in place

Ensure compressor discharge and suction shut-off valves are open

Ensure all pressure and safety controls are adjusted properly

Is the room thermostat set for normal operation?

Compressor Superheat Measurement

Measure the suction pressure at the suction service valve of the compressor

Determine the saturated temperature from the Pressure-Temperature chart

Measure the suction temperature of the suction line

Calculate the actual superheat at the compressor

Is the superheat within the range of 20 to 45 °F (11.2 to 25.2 °C)?

Describe any adjustments made to the suction superheat

Pressurize the system to a maximum of 150 psig (1136 kPa) with dry nitrogen

Is the system free of major leaks?

Detailed Leak Testing for A1 Refrigerants

Discharge the initial dry nitrogen charge and add refrigerant to raise the system pressure up to 10 psig (170 kPa)

Add dry nitrogen to increase the system pressure to a maximum of 150 psig (1136 kPa)

Use an electronic leak detector to check for leaks

Hold the pressure for a minimum of 12 hours

Recheck the system for leaks after 12 hours