Heatrae Sadia Megaflo Eco 125DD, Manual

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Descaling immersion heater(s)
`
Turn off the mains water supply, isolate the electrical
supply and turn off boiler
`
Attach a hosepipe to the drain cock having sufficient
length to take water to a suitable discharge point
below the level of the unit.
`
Open a hot tap close to the unit and open drain
cock to drain unit.
`
Open the cover(s) to the immersion heater
housing(s) and disconnect wiring from immersion
heater(s) thermostat(s).
`
Unscrew the immersion heater and withdraw the
immersion heater from the cylinder. Take care when
lifting the immersion heater out of the cylinder and
work within safe working practices.
`
Carefully remove any scale from the surface of the
element(s).
CAUTION
DO NOT use a sharp implement as damage
to the element surface could be caused.
`
Ensure sealing surfaces are clean and seals are
undamaged, if in doubt fit a new immersion heater
gasket. (spare part number
7035165
)
`
Replace immersion heater(s), making sure not to
trap the immersion heater gasket.
`
Rewire, check, close and secure immersion heater
housing cover(s).
Expansion volume re-charge
The air volume within the Megaflo Eco will periodically
require recharging to ensure expanded water is
accommodated within the unit. A discharge of water
INTERMITTENTLY from the expansion valve will
indicate the air volume has reduced to a point where it
can no longer accommodate the expansion.
To recharge the air volume:
• Turn off the heat source to the cylinder
• Turn off the water supply to the unit by turning the
isolating valve on either the pressure reducing
valve or expansion valve. Turn the blue handle so
it lies 90
o
to the direction of flow.
• Open the lowest hot tap supplied by the Megaflo
Eco.
• Hold open the temperature & pressure relief valve
by twisting the knob on top of the valve until water
ceases to run from the tap and gurgling noise at
the valve stops.
• Close the temperature & pressure relief valve by
releasing the knob.
• Turn on the isolating valve by turning the blue
handle so it lies parallel to the direction of flow.
When water flows from the hot tap,close the tap.
• The air volume will be automatically recharged as
the unit refills.
• If after following this procedure water still discharges
from the expansion valve further advice should be
sought from a competent installer or the Megaflo
Service Division.
Re-commissioning
`
Check all electrical and plumbing connections are
secure. Close the drain cock.
`
With a hot tap open, turn on the cold water supply
and allow unit to refill.
`
DO NOT switch on the immersion heater(s) or
boiler until the unit is full.
`
When water flows from the hot tap allow to flow
for a short while to purge air and flush through any
disturbed particles.
`
Close hot tap and then open successive hot taps in
system to purge any air.
`
When completely full and purged check system for
leaks.
`
The heating source (immersion heater(s) or boiler)
can then be switched on.
INFO
http://www.baxi.co.uk/information-and-advice/how-to-
videos.htm