Operation; General - Heatrae Sadia Megaflo Eco 70i Manual

8. Operation

8.1 General

WARNING
If water discharges from the Temperature
`
& Pressure relief valve on the cylinder
shut down the heat source and/or switch
off the immersion heater(s). DO NOT
turn off the water supply. Contact a
competent installer for unvented water
heaters to check the system.
DO NOT tamper with any of the safety
`
valves fitted to the system. If a fault is
suspected contact a competent installer.
Disconnect from the mains electrical
`
supply before removing any covers.
DO NOT bypass the thermal cut-out(s)
`
in any circumstances.
Water stored at temperatures in excess
`
of 60 C can scald. Consideration to
o
blend down water delivery temperatures
at the point of use to a safe level should
be given
All electrical wiring should be carried
`
out by a competent electrician and be in
accordance with the latest I.E.E Wiring
Regulations.
Temperature controls – direct units immersion
heater(s)
A combined thermostat and thermal cut-out is
`
provided for each immersion heater fitted. The
thermostat is factory set to give a water storage
temperature of approx. 60
set to control between 10
usually have been done during installation and
commissioning. Adjustments can only be made by
opening the controls covers.
Access to the thermostat can be made by opening
`
the controls housing cover - DISCONNECT THE
ELECTRICAL SUPPLY BEFORE OPENING THE
COVER(S).
Temperature adjustment is made by rotating the
`
adjustment knob on the top of the thermostat. The
adjustment represents a temperature range of
10°C to 70°C (see page 20, fig 14 for method of
adjustment).
Maximum working temperature is 70°C. In very
`
hard water areas limit to 60/65°C to minimise the
build up of limescale on the immersion heater
element surfaces.
DO NOT bypass the thermal cut-out(s) in any
circumstances.
24
C, however it can be
o
C and 70 C. This will
o o
Temperature controls - indirect units
A combined thermostat and thermal cut-out is
`
provided for the control of the external boiler. The
thermostat is factory set to give a water storage
temperature of approx. 60
set to control between 10
usually have been done during installation and
commissioning. Adjustments can only be made by
opening the controls covers.
Access to the thermostat can be made by opening
`
the controls housing cover - DISCONNECT THE
ELECTRICAL SUPPLY BEFORE OPENING THE
COVER(S).
Temperature adjustment is made by rotating the
`
adjustment knob on the top of the thermostat. The
adjustment represents a temperature range of
10°C to 70°C (see page 20, fig 14 for method of
adjustment).
Maximum working temperature is 70°C. In very
`
hard water areas limit to 60/65°C to minimise the
build up of limescale on the heat exchanger coil
surfaces.
The boiler thermostat and thermal cut-out must
`
be wired in series with the 2 port motorised zone
valve supplied to interrupt the flow of primary water
around the heat exchanger coil when the control
temperature has been reached.
The controls fitted to the cylinder will affect the
`
temperature of the stored water only, other
controls will be provided in the system for time
and temperature control of the space heating
requirements. Consult the instructions provided
with those controls for details of adjustments.
DO NOT bypass the thermal cut-out(s) in any
circumstances.
Flow performance
When initially opening hot outlets a small surge in
flow may be noticed as pressures stabilise. This is
quite normal with unvented systems. In some areas
cloudiness may be noticed in the hot water. This is due
to aeration of the water, is quite normal and will quickly
clear.
Operational faults
Operational faults and their possible causes are
detailed in the Fault Finding section (page 27) of this
book. It is recommended that faults should be checked
by a competent installer
C, however it can be
o
C and 70 C. This will
o o