Rheem RAMP-JEZ Installation Instructions - Page 18

HIGH AND LOW PRESSURE CONTROLS (HPC OR LPC) These controls keep the compressor from operating in pressure ranges which can cause damage to the compressor. Both controls are in the low voltage control cir-cuit. High pressure control (HPC) is a manual reset which opens near 610 PSIG. Do not reset arbitrarily without first determining what caused it to trip. The low pressure control (LPC) is an automatic reset which opens near 50 PSIG and closes near 95 PSIG. NOTE: High and low pressure controls are standard on all (-)ANL, (-)APL, (-)APM models. FIELD INSTALLED ACCESSORIES COMPRESSOR CRANKCASE HEAT (CCH) While scroll compressors usually do not require crankcase heaters, there are instances when a heater should be added. Refrigerant migration during the off cycle can result in a noisy start up. Add a crankcase heater to minimize refrigeration migration, and to help eliminate any start up noise or bearing "wash out." NOTE: A crankcase heater heater should be installed if: the charge of the system exceeds the values in Tables 4 and 5, if the system is subject to voltage variations or when a low ambient control is used for system operation below 55°F. All heaters are located on the lower half of the compressor shell. Its purpose is to drive refrigerant from the compressor shell during long off cycles, thus preventing damage to the compressor during start-up. At initial start-up or after extended shutdown periods, make sure the heater is energized for at least 12 hours before the compressor is started. (Disconnect switch on and wall thermostat off.) TABLE 9 MAXIMUM SYSTEM CHARGE VALUES (-)ANL (-)ANL Model Size 18 24 30/31 36/37 42 43 48/49 60 Compressor Model Number ZP16K5E ZP21K5E ZP25K5E ZP34K5E ZP36K5E ZP38K5F ZP42K5E ZP54K5E Charge Limit Without Crankcase Heat (3 Phase) 8 lbs. 8 lbs. 8 lbs. 10 lbs. 10 lbs. 10 lbs. 10 lbs. 10 lbs. Charge Limit Without Crankcase Heat (1 Phase) 9.6 lbs. 9.6 lbs. 9.6 lbs. 12 lbs. 12 lbs. 12 lbs. 12 lbs. 12 lbs. TABLE 10 MAXIMUM SYSTEM CHARGE VALUES (-)APL (-)APL Model Size 18 24 30 36 42 48 60 Compressor Model Number ZP16K5E ZP20K5E ZP24K5E ZP31K5E ZP36K5E ZP42K5E ZP51K5E Charge Limit Without Crankcase Heat (1 Phase) 9.6 lbs. 9.6 lbs. 9.6 lbs. 9.6 lbs. 12 lbs. 12 lbs. 12 lbs. TABLE 11 MAXIMUM SYSTEM CHARGE VALUES (-)APM (-)APM Model Size 18 24 30 36 42 48 60 Compressor Model Number ZP16K5E ZP20K5E ZP24K5E ZP31K5E ZP34K5E ZP42K5E ZP51K5E Charge Limit Without Crankcase Heat (1 Phase) 9.6 lbs. 9.6 lbs. 9.6 lbs. 9.6 lbs. 12 lbs. 12 lbs. 12 lbs. 18