Pipe Length Dip Switch Settings; Refrigerant Filling Level; Refrigerant Recovering Method - Hitachi RAC-112SQB Installation Manual

□3-3 Pipe Length DIP Switch (DSW) Settings
Adjust DSW2 settings as shown below when the refrigerant pipe is under 5m or over 30m.
□3-4 Refrigerant Filling Level
(1) Refrigerant filling level and standard pipe length at shipping by model

Refrigerant filling level

(kg)
112SQB 3.2
125/140/160SQB 3.4
Calculate the additional pipe length before filling in additional
refrigerant to ensure the required quantity of refrigerant. Calculate the
required quantity of refrigerant as shown below and 3-2 Guidelines for
Additional Refrigerant Filling.
(2) Calculation of additional refrigerant filling
Pipe length L(m) calculation
a) L(m)<30m: No need of additional refrigerant.
b) L(m)>30m: Add refrigerant.
Calculate the required quantity of refrigerant as shown
below:
W (additional refrigerant) = ( L-l) x P
(Example)
L=34m
L-l =34-30=4m
Additional quantity of refrigerant
W=( L-l) x P=4m x 60 g/m =240g
(3) Fill in the additional quantity of refrigerant (W) calculated in (2).
□3-5 Recovering Refrigerant
Follow the steps below to recover refrigerant from the outdoor unit before
relocating the indoor and/or outdoor unit(s).
1) Connect the manifold gauge set with the gas interceptor valve and
liquid interceptor valve.
2) Turn on the A/C power.
3) Set DSW1-1 on the outdoor unit to ON (unit operation starts). Close
the liquid interceptor valve. Start refrigerant recovery.
4) When the low pressure (gas interceptor valve) is -0.01MPaG
(-75mmHg), quickly run the following actions:
1. Close the gas interceptor valve.
2. Set DSW1-1 to OFF (unit operation stops).
5) Shut down the power.
Caution: Make sure pressure is not below -0.01MPaG.
Pressure below -0.01MPaG will cause compressor damage.
Standard pipe length
(m): l
30
DSW2 (pipe length and auxiliary function setup)
Change settings when the refrigerant pipe is under 5m or over 30m
Factory Settings
Pipe is under 5m
Tolerance of refrigerant filling level: ±0.1kg.
Over- or under-filling of refrigerant will cause
anomalies or compressor fault. Fill in exact
level of refrigerant only.
Make sure R410A refrigerant is in liquid
form before filling.
L: Pipe length
l: Standard pipe length (30m)
P: Compensational value (60g/m).
Manifold
gauge set
12
Pipe is over 30m
Set DSW1-1 to
ON.
Gas interceptor valve
Liquid interceptor valve