Panasonic WU-144MF1U9E 3-Way Service Manual - Page 58

5. Recovering Refrigerant 3-WAY VRF SYSTEM Outdoor Unit Repair Procedures (6) Recover the remaining refrigerant from the indoor unit using the refrigerant recovery unit. NOTE To determine completion of refrigerant recovery, follow the instructions that came with the refrigerant recovery unit. Ball valve (separately purchased) Outdoor unit side Suction tube Discharge tube Liquid tube Manifold gauge Service port Solenoid valve kit Solenoid valve kit Refrigerant recovery 2 unit Refrigerant recovery cylinder Fig. 2-10 Indoor unit 5-2-3. Refrigerant recovery procedures (2): for indoor unit with no ball valve Refrigerant in all indoor units and the refrigerant tubing circuit must be pumped into the outdoor unit. The maximum refrigerant storage capacity per a single outdoor unit is approx. 529 oz. Thus, in order to collect all refrigerant from the system, a separate refrigerant recovery unit is necessary. Follow these procedures to correctly perform pump down. Perform work correctly, according to the work procedures given below. ➀ Connect the manifold gauge to the high- and low-pressure outlet ports on the outdoor unit where pump down will be performed. Be sure that no air enters the tubing at this time. ➁ Fully close the discharge tube valve on the outdoor unit where pump down will be performed. ➂ Follow the instructions in "5-2-1. Cooling operation (for all units)" and operate all units in Cooling mode for approximately 5 minutes. Then fully close the liquid tube valve on the outdoor unit where pump down will be performed. ➃ When the high-pressure gauge reaches 406.1 psi or higher, or the low-pressure gauge reaches 72.5 psi or below, at the outdoor unit where pump down is being performed, press the ON/OFF button on the outdoor unit maintenance remote controller to stop operation at all units. Then immediately fully close the suction tube valve on the outdoor unit where pump down is being performed. * If the outdoor unit maintenance remote controller is unavailable, follow the procedure below to stop all of the units. Pull out the SCT connector (2P) (YEL) (CN231) on the outdoor unit control PCB of the unit where pump down is being performed. When the SCT connector is pulled out, immediately alarm F12 (sensor trouble) occurs and all outdoor units stop operating. Be sure that you do NOT grasp the lead wire when pulling out the connector. Removing any other connector may not cause the units to stop. Therefore be sure to pull out the SCT connector only. CAUTION It is not necessary to recover the refrigerant from the balance tube. Therefore do not operate the balance tube valve. ➄ Turn off power to all equipment in the system. Then pull out the RC1 connector (4P) (BLU) (CN106) on the outdoor control PCB in the outdoor unit for which pump down has been completed. * By pulling out the RC1 connector, communication between the main and the sub outdoor units will be isolated. ➅ Change the setting of controllable outdoor unit numbers (reduce by 1 unit). * If the setting is incorrect, the E30 alarm (outdoor unit serial communication signal error) occurs and the unit will not operate. ➆ Turn on power for all equipment in the system and let the remaining outdoor units run in Cooling mode. ➇ Repeat steps (1) through (7) and complete pump down for all outdoor units. 2 - 12