8
B
R
O
W
N
B
LU
E
G
R
E
E
N
/
Y
E
LL
O
W
FIG. 5 Typical installation - schematic
FIG. 6 Electrical Connections (Schematic)
DIRECT MODELS
INDIRECT MODELS
Note:
On models fitted with two or three elements each element must be
wired individually in accordance with the diagram above.
THERMOSTAT
EARTH
CONNECTION
FUSED (13A) DOUBLE
POLE ISOLATING
SWITCH
A
B
1.5mm
2
3 CORE
HOFR SHEATHED
CABLE
1 2
GREEN/YELLOW
13 AMP MAINS
SUPPLY. 1.5mm2
MIN. CABLE SIZE
TO INDIRECT SYSTEM
CONTROLS JUNCTION
BOX - SEE FIGS. 7/8
GREEN/
YELLOW
BROWN
BLUE
3
DIRECT THERMOSTAT
B
A
1
1
2
2 3
INDIRECT THERMOSTAT
INDIRECT THERMAL CUT-OUT
EXPANSION
VESSEL
COLD WATER
COMBINATION
VALVE
T&P RELIEF
VALVE
TO HOT
OUTLETS
MAINS
WATER
SUPPLY
ISOLATING
VALVE (NOT
SUPPLIED)
TUNDISH
DISCHARGE
PIPE
DRAIN COCK
(NOT SUPPLIED)
PRIMARY
RETURN
PRIMARY
FLOW
ELEMENT /
CONTROLS
HOUSING
INLET
BOOST ELEMENT
CONTROL HOUSING
(HSUDC120 TO HSUDC300
MODELS ONLY)
NOTE: PRIMARY HEATING COIL
FITTED ON HSUIC100 TO HSUIC300
MODELS ONLY
SECONDARY
RETURN
TAPPING (IF
REQUIRED)
BALANCED
COLD WATER
CONNECTION
(IF REQUIRED)
