Replacement Of Parts - Sime FORMAT SYSTEM 25 HE Installation And Servicing Instructions

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REPLACEMENT OF PARTS

6. 1 EXPANSION VESSEL
- Turn off power supply
- Remove boiler cover
- Isolate flow and return valve
- Drain boiler using fitted drain vent
- Disconnect expansion èipe
- Loosen top fixing screw and remove lower
fixing screw
- Remove vessel
- Check new vessel for correct pressure 1-
1.25 bar
- Refit in reverse order.
6.2 IGNITION/IONISATION
ELECTRODE
- Turn off power supply
- Remove boiler cover
- Remove sealed cover
- Disconnect electrode from ignition trans-
former
- Pull lead through grommet
- Remove electrode fixing screw
- Replace in reverse order.
6.3 MAIN BURNER
- Turn off power supply
- Isolate gas supply
- Remove boiler cover
- Remove sealed chamber cover
- Disconnect gas connection at injector
- Disconnect air sensing tube
- Disconnect two plugs to fan
- Remove ignition/ionisation electrode as
described in 6.2
- Remove 6x10 mm nuts securing burner
to heat exchanger
- Carefully lift out burner assembly
- Refit in reverse order
- Test for gas soundness.
6.4 FAN ASSEMBLY
- Remove burner assembly as described in
6.3
- Remove 4x8 mm bolts securing fan to
burner assembly
- Refit in reverse ensuring injector assem-
bly is fitted with arrow pointing from fan to
burner
- Recommision boiler
- Test for gas soundness.
6.5 MAIN HEAT EXCHANGER
- Turn off power supply
- Isolate gas supply
- Isolate flow and return valves
- Drain boiler using drain vent
- Remove burner assembly as described in
6.3
- Remove flue connection
- Disconnect 95° stat
- Disconnect 90° stat
- Remove condensate drain connections
- Remove upper auto air vent
- Disconnect flow and return connections
- Remove two fixing brackets
- Lift out heat exchanger
- Refit in reverse order
- Recommission boiler
- Test for gas soundness:
6.6 95° SMOKE STAT
- Turn off power supply
- Remove boiler cover
- Remove sealed chamber cover
- Disconnect 95° stat
- Unscrew from smoke chamber
- Refit in reverse order.
6.7 90° LIMIT STAT
- Turn off power supply
- Remove cover
- Remove sealed chamber cover
- Disconnect 90° stat
- Unscrew stat
- Replace in reverse order.
6.8 100° SAFETY STAT
- Turn off power supply
- Remove cover
- Remove sealed chamber cover
- Disconnect 100° safety stat
- Remove fixing screws
- Refit in reverse order.
6.9 THERMISTOR (SM SENSOR)
- Turn off power supply
- Remove cover
- Isolate flow and return valves
- Drain boiler using drain vent
- Disconnect thermistor
- Unscrew thermistor (catch any water
lost)
- Refit in reverse.
6. 1 0 GAS VALVE
- Turn off power supply
- Isolate gas supply
- Remove boiler cover
- Disconnect wiring from gas valve
- Disconnect sensing tube
- Remove gas valve complete with gas shut-
ter
- Split gas shutter from gas valve
- Refit in reverse order ensuring seals are
replaced as required
- Recommission boiler
- Check for gas soundness.
6. 1 1 GAS SHUTTER
- As gas valve 6. 1 0.
6. 1 2 PRINTED CIRCUIT BOARD (PCB)
- Isolate from power supply
- Remove screws securing control panel
- Lower panel to horizontal position
- Remove PCB cover
- Disconnect all wiring
- Remove heat control knobs
- Remove PCB fixing screws
- Transfer trimmer spindles to new board
- Ensure PCB links are matched to old
board
- Refit in reverse order
- Recommission boiler.
6. 1 3 PUMP MOTOR
- Turn off power supply
- Remove boiler cover
- Isolate flow and return valves
- Drain boiler using drain vent
- Remove plug connection
- Remove 4 x fixing screws, catch any lost
water
- Refit in reverse using new gasket.
6. 1 7 TOP AUTO AIR VENT (AAV)
- Turn off power supply
- Isolate flow and return valves
- Drain boiler using drain vent
- Unscrew AAV
- Refit in reverse.
6. 1 8 INTERNAL AUTO AIR VENT (AAV)
- Turn off power supply
- Isolate flow and return valves
- Remove boiler cover
- Drain boiler using drain vent
- Remove AAV
- Replace in reverse order.
6. 1 9 SAFETY VALVE
- Turn off power supply
- Isolate flow and return valves
- Remove boiler cover
- Drain boiler using drain vent
- Disconnect pipe from safety valve
- Remove safety valve securing clip
- Remove safety valve, catch any water lost
- Refit in reverse.
6.20 PRESSURE/TEMPERATURE
GAUGE
- Turn off power supply
- Isolate flow and return valves
- Remove boiler cover
- Drain boiler using drain vent
- Remove the clip securing the pressure
sensor
- Remove the clip securing thermometer
bulb
- Carefully remove the gauge
- Refit in reverse order.
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