Benchmark Metropolis DGT 25 BF, Installation And Servicing Instrucnion

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- Remove the air pressure switch fixing
bracket.
- Transfer the bracket to the new air pres-
sure switch.
- Refit in reverse order.
6.8 DHW SENSOR (SB)
- Isolate the boilers power supply
- Remove the boiler cover, see 4.3.
- Disconnect the SB sensor from the pipe.
- Disconnect the electrical connections.
- Refit in reverse order.
6.9 GAS VALVE
- Isolate the boilers power supply
- Remove the boiler cover, see 4.3.
- Isolate the gas supply.
- Disconnect the electrical connection to
the gas valve.
- Disconnect the vent pipe.
- Disconnect the upper and lower gas con-
nections.
- Refit in reverse order, using new gaskets.
- Reset the gas valve as described in 4.2.1
and 4.2.2.
- Ensure that the tightness of the gas con-
nections on completion of the work.
6.10 PUMP
- Isolate the boilers power supply.
- Remove the boiler cover, see 4.3.
- Close the flow and return isolation valves.
- Drain the boiler using the fitted drain
vent, see fig 15.
- Disconnect the electrical connections to
the pump.
- Remove the four fixing screws.
- Refit in reverse order.
6.11 AIR RELIEF VALVE (AAV)
- Isolate the boilers power supply
- Remove the boiler cover, see 4.3.
- Close the flow and return isolation valves.
- Drain the boiler using the fitted drain
vent, see fig 15.
- Remove the clip securing the AAV
- Remove the AAV
- Replace in reverse order.
6.12 PRINTED CIRCUIT BOARD
- Isolate the boilers power supply
- Remove the boiler cover, see 4.3.
- Remove the control panel fixing screws.
- Lower the panel and remove the rear
cover.
- Disconnect the wiring from the PCB
- Unclip the PCB from the control panel.
- Refit in reverse order, pay particular
attention to the connection of the ignition
electrode, ensure that it is positioned on
the terminal and not down the side of it.
- The new PCB will require configuring as
shown in 3.2
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ENG
IT
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