a
b
b
d
c
12
Service access
(233)
11
0
357
348
233
48
133
223
308
365
461
84
124
530
324.5
100.5
860
637
Letter
Pipe description
Connection size/type
A
Space heating and cooling/
Indirect DHW tank (primary)
return connection
G1 nut
B
Space heating and cooling/
Indirect DHW tank (primary) fl ow
connection
G1 nut
C
Refrigerant (Liquid)
9.52 mm/Flare
D
Refrigerant (Gas)
15.88 mm/Flare
E
Discharge pipe (by installer) from
pressure relief valve
G1/2” female (valve port within hydrobox casing)
F
Electrical cable inlets
—
For inlets and , run low-voltage wires including
external input wires and thermistor wires. For inlets
and , run high-voltage wires including power
cable, indoor-outdoor cable, and external output
wires.
*For a wireless receiver (option) cable, use inlet .
G
Drain socket
O.D. ø20
A
B
C
D
E
<ERSC> (Split model system)
<Front>
<Right side>
<Rear>
<View from below>
Earth leakage
circuit breaker
Terminal block
Main controller
Pressure relief
valve
G
Automatic air vent
F
5-2. Service access diagrams
Service access
Parameter
Dimension (mm)
a
200
b
150
c
500
d
500
Suffi cient space MUST be left for the provision of discharge pipework as detailed
in National and Local building regulations.
The hydrobox must be located indoors and in a frost-free environment, for
example in a utility room.
OCH532A
