Heatrae Sadia Megaflo Eco Solar Series, Product Manual

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Unvented Hot Water Cylinder
Unvented Hot Water Cylinder
INST
ALLA
TION AND
COMMISSIONING INSTRUCTIONS (2)
Wiring
All electrical wiring should be carried out by a competent electrician and be in accordance with the latest I.E.E. Wiring Regulations.
The MEGAFLO Eco Solar Indirect combined thermostat and thermal cut-out are factory pre-wired. The 2-port motorised valve supplied MUST be
wired in series with the Indirect controls such that the power supply to the valve is interrupted should either the Thermostat or Thermal cut-out
operate. The Figures 13 and 14 (see p. 21) detail the wiring required between these controls and the motorised valve. Wiring to external controls
is made via the terminal block fitted. The cable should be routed through the aperture in the terminal cover and secured using the cable grip
provided.
The Indirect Thermal cut-out MUST NOT be bypassed.
Heating System Controls
The controls provided with the MEGAFLO Eco Solar will ensure the safe operation of the MEGAFLO Eco Solar within a central heating system.
Other controls will be necessary to control the space heating requirements and times that the system is required to function. Depending on the
boiler selected, heating circuit design and controls used it may be beneficial to incorporate a system bypass in the heating system pipework.
The MEGAFLO
Eco
Solar is compatible with most heating controls, examples of electrical circuits are given in Figures 13 and 14, (see p. 21).
However, other systems may be suitable,
refer to the controls manufacturers’ instructions, supplied with the controls selected, for
alternative system wiring schemes.
Immersion Heater(s)
The MEGAFLO Eco Solar indirect units (Indirect models) are supplied with an immersion heater which can be used as an alternative heat source
should the boiler supply need to be isolated from the MEGAFLO Eco Solar unit. The immersion heater is located within the controls housing.
refer to sections, “Wiring and Operation” (see p.22). for details of wiring and operation of the immersion heater, 210 litre models and above are
supplied with a second blanked off boss which can be used for the connection of a second immersion heater should this be required.
To remove the blanking plug:
Ensure the cylinder is drained of water first. Open the cover to the upper immersion heater boss. Unscrew the brass backnut using the key spanner
provided with the unit. Remove the blanking plate and sealing gasket from the boss.
Fitting additional immersion heater:
Insert the immersion heater and sealing gasket into the upper boss. Ensure that the sealing gasket is not displaced when inserting. It may be helpful
to support the immersion heater using a round shafted 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. If an additional immersion heater and thermostat assembly is
required order part no. 95:970:554
Figure 12 - Indirect Wiring layout
L N 1 2 3
Control Housing Details
Element Connections
1.5mm² 3 Core
HOFR sheathed
cable Indirect control
wiring