Maximum Safety Sensor; Flue Overheat Thermostat; Auto Air Vent; Gas Valve - Worcester 27Ri Compact Installation, Commissioning And Servicing Instructions

SERVICE AND SPARES

6.8.5 "MAXIMUM SAFETY SENSOR"

▶ Disconnect the electrical connectors to the "Maximum safety sensor".
1. Remove the screw securing the sensor.
2. Remove the sensor from the heat exchanger.
▶ When replacing the sensor, ensure that the assembly is properly
located on the orientation pin.
Fig. 80 Overheat sensor

6.8.6 FLUE OVERHEAT THERMOSTAT

▶ Disconnect the lead to the thermostat.
Take care not to damage the housing when removing the
thermostat.
▶ Using a small screwdriver, gently prise the thermostat from the
housing taking care not to damage the housing or grommet.
Fig. 81 Flue overheat thermostat
▶ To replace, push the thermostat and new grommet gently back into
the opening until contact with the locating ridge is felt.
▶ The Flueway will have to be removed if the thermostat falls into the
housing, refer to section 6.8.9.
40
2.
1.

6.8.7 AUTO AIR VENT

Ensure that the boiler has been fully drained.
1. Remove the spring clip completely.
2. Lift the air vent out of the housing and remove.
Fig. 82 Auto air vent
When re-assembling ensure that the "O" ring is fitted to the Auto air vent
and NOT the heat exchanger, otherwise the Air vent will be difficult to fit.
Apply silicone grease to the "O" ring to ease assembly.

6.8.8 GAS VALVE

▶ Isolate the gas supply at the boiler gas cock.
▶ Remove the combustion air inlet pipe.
▶ Disconnect the electrical connector from the valve
1. Remove the gas pipe from the top of the valve.
2. Undo the bottom gas pipe connection.
3. Remove the screw securing the gas valve.
4. Lift the gas valve to clear the bottom gas connection.
5. Pull the gas valve forward out of the boiler.
4.
Fig. 83 Gas valve
▶ When fitting the new valve, start the bottom gas connection and
tighten by hand before making any other connections to the valve.
▶ Secure the valve with the screw.
▶ Tighten the bottom connection firmly with a suitable spanner.
▶ Connect the top gas pipe.
▶ Reconnect the electrical connector.
▶ Check that all the gas connections for gas tightness.
▶ Open the boiler gas isolator.
Greenstar Ri Compact 6 720 646 610 (2013/12)
2.
1.
1.
5.
3.
2.