Commissioning - Heatrae Sadia MegaFlo Installation Manual

6

Commissioning

6.1 FILLING AND FLUSHING THE MEGAFLO 6.1 FILLING AND FLUSHING THE MEGAFLO
Ensure that all fi ttings and immersion heaters are correctly fi tted and tightened. An immer-
sion heater key spanner is provided to aid in tightening the immersion heater(s).
i) Open a hot tap furthest from the Megafl o.
ii) Open the isolating valve on the Cold Water Combination Valve by turning the black
handle so that it lies parallel to the direction of fl ow. Open the mains stop cock to fi ll
the unit. When water issues from the tap, allow to run for a few minutes to thoroughly
fl ush through any residue, dirt or swarf, then close tap.
iii) Open successive hot taps to purge any air from the system.
iv) Check all connections for leaks and rectify as necessary.
v) The Strainer housed within the Cold Water Combination Valve should be cleaned to
remove any debris that may have been fl ushed through the main supply pipe. Refer
to Section 8.3 for instructions on how to do this.
6.2 CHECK THE OPERATION OF THE SAFETY 6.2 CHECK THE OPERATION OF THE SAFETY
VALVES VALVES
i) Slowly manually open, for a few seconds, the Temperature and Pressure Relief Valve
situated on the Megafl o unit (see Figure 15). Check water discharged runs
freely away through the tundish and discharge pipework. Close valve, ensure
water fl ow stops and valve reseats correctly.
ii) Repeat for the Expansion Valve situated on the Cold Water Combination Valve or
Expansion Core Unit (see Figures 2 and 3).
6.3 DIRECT UNITS 6.3 DIRECT UNITS
Switch on the electrical supply to the immersion heater(s) and allow the unit to heat up.
Check that the thermostat operates correctly. A storage temperature of approx. 60
ommended (between graduations 4 and 5 on the thermostat). If necessary the temperature
can be adjusted by inserting a fl at bladed screwdriver in the adjustment knob on top of the
immersion heater thermostat and rotating (see Figure 10). The adjustment range 1 to 5
represents a temperature range of between 10
Check that no water is discharged from either the Expansion Valve or Temperature and
Pressure Relief Valve during the heating cycle.
6.4 INDIRECT UNITS 6.4 INDIRECT UNITS
Fill the indirect (primary) circuit following the boiler manufacturer's commissioning instruc-
tions. To ensure the primary heating coil in the Megafl o is fi lled the 2-port motorised valve
(supplied) should be manually opened by moving the lever on the motor housing to the
MAN OPEN setting. When the primary circuit is full return the lever to the AUTO position.
Vent any trapped air by opening the air bleed.
and 70 C.
o o
C is rec-
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