Lift grille from unit. 4. Disconnect compressor leads (crankcase heater, low-pressure switch, defrost thermostat and solenoid coil) from electrical components and pull them thru the wire access opening into the PRESSURE AT LIQUID SERVICE VALVE coil section. Lift fan orifice/control ring after pinching and pressing down on 3 plastic pins of tube supports. 5. Remove louvered casing by taking out 16 screws securing it to the cabinet and sliding it away from the coil. 6. Using a midget tubing cutter, cut liquid and discharge lines on the coil and suction and discharge lines at a convenient place near the compressor for easy reassembly with copper slip couplings. 7. After plugging connections, remove condenser coil by pinching plastic pins of tube supports that extend into basepan and lift vertically. Set coil on a clean, flat surface. 8. Remove compressor holddown bolts and slide out compressor. Remove crankcase heater. CHARGING AND Fig. 8 — 38QB015 with 28HQ.VQ018, 40AQ018 or 40DQ018 Cooling Cycle Charging Chart 9. Carefully unbraze suction and discharge line piping stubs from compressor after noting position of stubs to assist when reinstalling. 10. Install new compressor, placing crankcase heater around compressor. Be sure compressor holddown bolts are in place. 11. Replace coil; braze suction and discharge lines to compressor piping stubs (at points where cut, Step 6); rewire compressor and leak test. 12. Replace fan orifice/control ring; connect compressor wires after feeding them thru control ring; replace fan/grille assembly and rewire; connect high- and low-voltage power wiring; and replace louvered casing. 13. Replace top cover by running 4 screws into orifice loosely (2 on each side of unit) and tighten when cover is in place. Replace remaining screws. 14. Evacuate and recharge system. CHECK CHARTS Fig. 9 — 38QB015 with 28HQ,VQ018, 40AQ018 or 40DQ018 Heating Cycle Operation Check Chart 10 (kPa) PRESSURE AT SUCTION SERVICE VALVE Fig. 10 — 38QB018 with 28HQ,VQ024, 40AQ024, or 40DQ024 Cooling Cycle Charging Chart (kPa) PRESSURE AT SUCTION SERVICE VALVE Fig. 12 — 38QB024 with 28HQ,VQ024,030, 40AQ024,030 or 40DQ030 Cooling Cycle Charging Chart Fig. 11 — 38QB018 with 28HQ.VQ024, 40AQ024 or 40DQ024 Heating Cycle Operation Check Chart Fig. 13 — 38QB024 with 28HQ,VQ024,030, 40AQ024.030 or 40DQ030 Heating Cycle Operation Check Chart 11 (kPa) PRESSURE AT SUCTION SERVICE VALVE Fig. 14 — 38QB030 with 28HQ,VQ030,036, 40AQ030,036, 40DQ030 or 40FS160 with 28HQ,VQ036 Cooling Cycle Charging Chart (kPa) PRESSURE AT SUCTION SERVICE VALVE Fig. 16 — 38QB036 with 40AQ036,042, 28HQ,VQ036,042, 40QB,QH042 or 40FS160 with 28HQ,VQ036,042 Cooling Cycle Charging Chart Fig. 15 — 38QB030 with 28HQ,VQ030,036, 40AQ030,036, 40DQ030 or 40FS160 with 28HQ,VQ036 Heating Cycle Operation Check Chart (kPa) SUCTION PRESSURE AT SERVICE PORT Fig. 17 — 38QB036 with 40AQ036,042. 28HQ,VQ036,042, 40QB,QH042 or 40FS160 with 28HQ,VQ036,042 Heating Cycle Operation Check Chart 12 PSIG (441) (469) (496) (524) (552) (579) (kPa) PRESSURE AT SUCTION SERVICE VALVE Fig. 18 — 38QB042 with 40QB,QH042, 28HQ,VQ042 or 40FS160 with 28HQ.VQ042 Cooling Cycle Charging Chart (kPa) PRESSURE AT SUCTION SERVICE VALVE Fig. 20 — 38QB048 with 28HQ,VQ048, 40FS200 with 28HQ,VQ048 or 40QB.QH048 Cooling Cycle Charging Chart 50 (345) SUCTION PRESSURE AT SERVICE PORT 60 (4I4) Fig. 19 — 38QB042 with 40QB,QH042. 28HQ.VQ042 or 40FS160 with 28HQ,VQ042 Heating Cycle Operation Check Chart 33 F 10 PSIG <69> (kPo) * HFf ' ( A / $ m ■ P / / ..... ¥ i r+!~ / 'i fs- T7"ÎT' 1 -t-H- | ; 15 rfi rttf : 60 F : : (I5.6C)i iW-:i DRY-BULB TEMP AIR : ENT INDOOR UNIT 20 30 40 50 (138) (207) (276) (345) SUCTION PRESSURE AT SERVICE PORT Fig. 21 — 38QB048 with 28HQ,VQ048, 40FS200 with 28HQ,VQ048 or 40QB,QH048 Heating Cycle Operation Check Chart 13 (kPa) PRESSURE AT SUCTION SERVICE VALVE Fig. 22 — 38QB060 with 40QB,QH060 Cooling Cycle Charging Chart (kPa) SUCTION PRESSURE AT SERVICE PORT Fig. 23 — 38QB060 with 40QB.QH060 Heating Cycle Operation Check Chart Filter Drier — Install field-supplied filter drier (Table 3) in system liquid line when refrigerant system is opened for service as described under Compressor Removal. Position drier in liquid line at convenient location. Pumpdown Procedure — The system may be pumped down in order to make repairs on low side without losing complete refrigerant charge. 1. Attach pressure gage to suction service valve gage port. 2. Frontseat the liquid line valve. 3. Start unit and run until suction pressure reaches 5 psig (35 kPa) (see Caution). 4. Shut unit off and frontseat suction valve. 5. Vent remaining pressure to atmosphere. Unit Controls and Safety Devices HIGH-PRESSURE RELIEF VALVE is located in compressor. Relief valve opens at a pressure differential of approximately 500 psig (3448 kPa) between suction (low side) and discharge (high side) to allow pressure equalization. INTERNAL...