Installation - Direct Units - Heatrae Sadia MegaFlo Installation Manual

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Installation - Direct units

4.1 IMMERSION HEATER(S) 4.1 IMMERSION HEATER(S)
The Megafl o is supplied with either one (D models), two (DD models) or three (DDD models)
factory fi tted immersion heaters. Each immersion heater is rated 3kW at 240V.
The DDD models are supplied with three immersion heaters and a blanking plug fi tted to the
uppermost of the three lower immersion heater bosses. Should a different combination be
required the blanking plug and the upper (boost) immersion heater can be swapped.
To remove the blanking plug:
Ensure the cylinder is drained of water fi rst. Open the cover to the uppermost of the three lower
immersion heater bosses. The cover is secured by a cross-headed screw. Unscrew brass
backnut using the key spanner provided with the unit. Remove the blanking plate and sealing
gasket from the boss.
To remove the immersion heater:
Open the cover to the upper immersion heater. Unplug the thermostat from the element by gen-
tly pulling the thermostat outwards. Unscrew the brass backnut using the key spanner provided.
Remove the immersion heater assembly and sealing gasket from the boss.
Replacement:
Insert the immersion heater and sealing gasket into the required boss. Ensure that the sealing
gasket is not displaced when inserting. It may be helpful to support the immersion heater using
a round bladed screwdriver inserted into one of the thermostat pockets. Hand tighten the brass
backnut. Secure the immersion heater in position by tightening with the key spanner provided.
Insert the blanking plate into the remaining boss ensuring the sealing gasket is not displaced
when inserting. Hand tighten the brass backnut. Secure in position by tightening with the key
spanner provided.
If an additional immersion heater is required order part no. 95 970 510.
4.2 WIRING (see Figure 8) 4.2 WIRING (see Figure 8)
All electrical wiring should be carried out by a competent electrician and be in accordance
with the latest I.E.E. Wiring Regulations. Each circuit must be protected by a suitable fuse and
double pole isolating switch with a contact separation of at least 3mm in both poles.
The immersion heater(s) should be wired in accordance with Diagram 9. The immersion heat-
ers MUST be earthed. The supply cable should be 1.5mm
be routed through the cable gland provided with the outer sheath of the cable fi rmly secured by
tightening the screw on the cable gland. Replace the immersion heater cover(s) before operat-
ing ensuring that the threaded edge clip is in position to provide a suitable thread for the cover
screw.
DO NOT OPERATE THE IMMERSION HEATER(S) UNTIL THE MEGAFLO HAS BEEN DO NOT OPERATE THE IMMERSION HEATER(S) UNTIL THE MEGAFLO HAS BEEN
FILLED WITH WATER. FILLED WITH WATER.
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3 core HOFR sheathed and must
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