Certikin MB20S, Operating, Installation And Servicing Instructions

Page: 35 / 40

6.0 Servicing
35
Genie S
Gas valve
(See 6.4 for illustration)
• Remove the ignition control, see above.
• Release the gas elbow by undoing the four shoulder
bolts holding it to the gas valve. Remove the off set
tube from the gas valve by pushing the end of the
connector inwards and then pulling the pipe out.
Unscrew the off set connector and transfer to the new
gas valve.
• Release the gas valve from the venturi by undoing
three screws.
IMPORTANT: Ensure the rubber seal (and
ori
fi ce if propane) is transferred from the
old Valve and placed between the venturi
and gas valve before assembly.
• Replacement is the reverse.
• Fire up the heater and check for gas leaks.
• After fi ve minutes check the rate and combustion
is correct to the data table. (inside cover). Adjust
using the throttle on the gas valve.
Fan
(See 6.4 for illustration)
• Remove the two electrical connectors on the fan.
• Remove the two screws holding the venturi to the
fan.
• Undo the four nuts holding the fan to the heat ex-
changer and withdraw.
(See 6.4 for illustration)
• Transfer the venturi gasket to the new fan.
• Replacement is the reverse.
Venturi
(See 6.4 for illustration)
• Remove the ignition control and gas valve, see
above.
• Pull off the air tube (See 6.4 for illustration)
• Undo the two screws holding the venturi to the
fan and remove.
• Ensure the gasket is transferred to the new venturi or
positioned on the fan before positioning the replace-
ment.
• Replacement is the reverse.
• Fire up the heater and check for gas leaks.
• After fi ve minutes check the rate and combustion is
correct. (see inside cover). Adjust using the throttle
on the gas valve if required.
(See 6.4 for illustration)
Pump
(See 6.4 for illustration)
• Drain the primary waterside of the heater.
• Disconnect the pump mains lead from the six way
connector in the electrical chassis.
• Undo the two water connections of the pump and
remove.
• Transfer the mains lead to the new pump.
• Replacement is the reverse.
IMPORTANT
: It is essential that all the air
is removed from the heat exchanger before
the heater is
fi red. Operating the heater
which contains air inside may damage the
heat exchanger and invalidate the warranty.
Expansion vessel
(See 6.4 for illustration)
• Remove the single screw holding the retaining
strap.
• Release the fl exible hose connection to the vessel
and remove it.
• Replacement is the reverse.
Heat exchanger
(See 6.4 for illustration)
• Remove the expansion vessel
• Remove the spacer below the secondary heat
Exchanger by removing the two screws and pull-
ing forward.
• Release both the heat exchanger demountable
connections.
(See 6.4 for illustration)
• Undo the screws holding the panels around the
demountable connections.
(See 6.4 for illustration)
• Lower pipework away from the heat exchanger.
• Remove the front top panel and disconnect the
fl ue thermostat connections.
• Pull the air duct and fl ue up and away from the
heater fl ue adapter.
• Disconnect the heat exchanger combustion sen-
sor by pressing the latch and pulling off .
• Remove the four screws holding the rear top
panel.
• Lift the rear top panel with the fl ue adapter clear of
the heat exchanger.
• Remove the fan, gas valve and ignition controller.
• The heat exchanger is now only retained by the
two side brackets and releasing the four front
screws will enable it to be pulled forward. Before
releasing ensure there is support available.
• Replacement is the reverse.

IMPORTANT :
In order to maintain suf-
fi cient frost protection levels it is rec-
ommended that after a drain down, the
heater is re-
fi lled with a suitable anti-
freeze. The manufacturer recommends
Sentinal X500 or Fernox Alphi 11
Secondary heat exchanger
(See 6.4 for illus-
tration)
• Drain the pool side suffi ciently so that the
heaters pool connections can be released.
• Remove the case retaining plates around the
heater’s pool connections.
• Drain the primary system with the drain cock
provided. Ensure an air vent is open to fully re-
lease the water.
• Remove the pool sensor from the secondary
heat exchanger.
• Remove the expansion vessel.
• Remove the two fi xing screws holding the spacer
below the secondary heat exchanger.
• Pull the space out & forwards to remove.
• Undo the primary compression connections on
the secondary heat exchanger and allow it to
drop off its connections and remove.
• Remove the four screws fi xing the secondary heat
exchanger to its mounting plate.
• Replacement is the reverse.