Installation
6 720 805 339 (2014/09)
19
Connecting the immersion heater (Heaters conform to
EN60335.2.73)
It is essential that the water level within the tank or cylinder is such that
water fully covers the heating elements to a depth of at least 100 mm.
Under no circumstances must the heater be permitted to run dry -
serious damage may result to the heater in addition to danger of
personal injury & damage to property.
Check the heater for possible leakage before wiring. See below for
schematic wiring diagram.
Wire the heater through a double-pole fused spur, having contact
separation of at least 3 mm, with a minimum breaking capacity of
13 Amps.
Use a rigid cable, 2 m long max, with 1.5 mm
2
cross-section and a
temperature resistance of at least 85°C. Rubber Insulated HOFR
Sheathed, complying with BS6141 Table 8. It must be fully earthed.
Ensure all terminal connections are securely made. Do not however use
excessive force when tightening the terminal screws.
NEMKO Approval will only apply to this heater if the Thermowatt RTS
plus thermostat is used.
Immersion heater conforms with EEC Directive 76/889 for Radio
Interference and comply with BS800: 1977.
WIRING THE IMMERSION HEATER:
▶ Remove the terminal cover from the immersion heater. Use the
accessories supplied in the plastic bag located under the cover of the
immersion heater to complete the wiring.
Fig. 16 Wiring diagram
E
Earth (Green/Yellow)
N
Neutral (Blue)
L
Live (Brown)
Fig. 17 Rigid cable end preparation
E
Earth (Green/Yellow)
N
Neutral (Blue)
L
Live (Brown)
▶ Provide 90 mm length for the Live (L) and Neutral (N) cables and
bare the end of each cable 8 mm minimum.
▶ Provide 105 mm length for the Earth cable (E) and bare the end of
the cable 20 mm minimum. Make a circle with the end of the Earth
cable (E) to turn around the earth stud (1) to ensure a full contact
between the cup washer (6) and the plain washer (4) (refer to the
fitment of earth cable to stud).
▶ Fit the Live and Neutral cables on the thermostat.
Fig. 18 Fitment of earth cable to stud
[1]
Earth stud
[2]
Nuts (x2) *
[3]
Shake-proof washer *
[4]
Plain washer *
[5]
Earth cable
[6]
Cup washer *
[*]
supplied in the plastic bag
▶ Ensure the mains voltage corresponds to the voltage
rating of the heater as shown on the rating label on
the terminal cover.
▶ Only use rigid wires 1.5 mm
2
for main supply.
Flexible wire may cause poor electrical connection to
the heater, resulting in overheat.
▶ When connecting the thermostat please ensure the
male pins are securely located within the female
sockets.
▶ Accessories (washers, cable grip, screws…)
delivered in the plastic bag under the terminal cover
of the heater have to be used to complete the
connection to the earth and to fix the rigid cable.
DANGER:
Risk of electric shock!
▶ Isolate from mains supply.
▶ This heater must be earthed.
E
N
L
AQU-32-3W
L
N
E
E
AQU-33-3W
105
90
20
8
L = 2 m max
(3x1.5 mm² - 85 °C)
