Carrier 38APS025 Manual

Also see for 38APD115: Installation instructions

Carrier 38APS025 Manual Manual pdf 41 page image

41START-UPCompressor crankcase heaters must be on for 24 hours be-fore start-up. To energize the crankcase heaters, close the fielddisconnect and turn on the fan circuit breakers. Leave the com-pressor circuit breakers off/open. The crankcase heaters arenow energized.Preliminary Charge — Refer to GTAC II (GeneralTraining Air Conditioning), Module 5, Charging, Recovery,Recycling, and Reclamation for charging procedures. Usingthe liquid charging method and charging by weight procedure,charge each circuit with the amount of Puron® refrigerant(R-410A) listed in Table 11. This table is based on 25 ft (7.6 m)of liquid line and does not include the indoor coil refrigerantcharge which must be added to the preliminary charge amount.For liquid lines longer than 25 ft (7.6 m), additional charge isrequired and can be found in the notes section of the table.Adjust Refrigerant ChargeTable 11 — Preliminary Puron Refrigerant (R-410A)Charge, lb (kg)NOTES:1. Preliminary charge is based on 25 ft (7.6 m) of interconnecting liquid linepiping between indoor and outdoor units.2. For liquid line piping longer than 25 ft (7.6 m), use the followinginformation:1/2 in. (12.7 mm) liquid line — 0.6 lb per 10 linear ft (0.27 kg per 3 m)5/8 in. (15.9 mm) liquid line — 1.0 lb per 10 linear ft (0.45 kg per 3 m)7/8 in. (22.2 mm) liquid line — 2.0 lb per 10 linear ft (0.91 kg per 3 m)11 /8 in. (28.6 mm) liquid line — 3.5 lb per 10 linear ft (1.59 kg per 3 m)1 3 /8 in. (34.9 mm) liquid line — 5.1 lb per 10 linear ft (2.32 kg per 3 m)Due to the compact design of microchannel heat exchang-ers, refrigerant charge is reduced significantly. As a result,charging procedures for MCHX units require very accuratemeasurement techniques. Charge should be added in smallincrements. Using cooling charging charts provided, add orremove refrigerant until conditions of the chart are met. Asconditions get close to the point on the chart, add or removecharge in 1/4 lb. (0.11 kg) increments until complete. Ensurethat all fans are on and all compressors are running when usingcharging charts. If the unit is equipped with a digital compres-sor, disable the digital operation while charging the machine tomaintain stable operation. To disable the digital compressoroperation, set ConfigurationoUNIToA1.TY (CompressorA1 Digital?) to NO. Be sure to re-enable the digital operationafter charging operation is complete. If charging at low out-door ambient, the condenser coil can be partially blocked inorder to increase head pressure.NOTE: Do not use recycled refrigerant as it may containcontaminants.IMPORTANT: Before beginning Pre-Start-Up or Start-Up,review Start-Up Checklist at the back of this publication.The checklist assures proper start-up of a unit and provides arecord of unit condition, application requirements, systeminformation, and operation at initial start-up.CAUTIONCrankcase heaters on all units are wired into the control cir-cuit, so they are always operable as long as the main powersupply disconnect is on (closed), even if any safety deviceis open. Compressor heaters must be on for 24 hours priorto the start-up of any compressor. Equipment damagecould result if heaters are not energized for at least 24 hoursprior to compressor start-up.CAUTIONNever charge liquid into the low pressure side of system.Do not overcharge. During charging or removal of refriger-ant, be sure indoor fan system is operating. Failure to com-ply could result in personal injury or equipment damage.CAUTIONCharging procedures for MCHX (microchannel heatexchanger) units require very accurate measurement tech-niques. Charge should be added in small increments. Usingcooling charging charts provided, add or remove refriger-ant until conditions of the chart are met. As conditions getclose to the point on the chart, add or remove charge in1/4 lb (0.11 kg) increments until complete. Ensure that allfans are on and all compressors are running when usingcharging charts (Fig. 50-76). Failure to comply may resultin equipment damage.38AP UNIT SIZE CIRCUIT A CIRCUIT B38APS025 24 (10.9) —38APD025 12 (5.6) 12 (5.6)38APS027 26 (11.6) —38APD027 13 (6.0) 13 (6.0)38APS030 29 (12.9) —38APD030 14 (6.5) 14 (6.5)38APS040 39 (17.7) —38APD040 21 (9.5) 17 (7.8)38APS050 48 (21.5) —38APD050 22 (9.9) 26 (11.6)38APD060 27 (12.1) 29 (12.9)38APS065 — 55 (25.0)38APD070 29 (12.9) 33 (15.1)38APD080 29 (12.9) 46 (20.7)38APD090 39 (17.7) 46 (20.7)38APD100 46 (20.7) 46 (20.7)38APD115 46 (20.7) 55 (25.0)38APD130 46 (20.7) 71 (32.3)IMPORTANT: For proper charging, units equippedwith a digital compressor must have the digital com-pressor operation disabled to maintain stable operation.To disable digital compressor operation, set Configura-tiono UNITo A1.TY (Compressor A1 Digital?) toNO. Be sure to re-enable the digital operation aftercharging operation is complete.