ICI Caldaie RIO 140 Installation And Servicing Manual - page 29
9
REPLACEMENT OF COMPONENTS
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7 Re-assemble in reverse order, ensuring the front return edge of the control box top is located under the
front panel return.
8 Test the boiler as described in section 7.5, paragraphs 1,2 and 3.
9.18 SYSTEM TEMPERATURE/PRESSURE GAUGE
1 Ensure that the electricity supply has been isolated.
2 Drain the central heating circuit of the boiler as described in section 8.
3 Remove the four screws securing the control box top cover. Slide the cover back and up to remove it from
the control box.
4 Remove the union nut securing the pressure sensor to the front of the safety valve (to the left of the gas
valve) and withdraw the sensor. Withdraw the temperature phial from the pocket on the central heating
flow pipe (also to the left of the gas valve).
5 Squeeze together the locating tabs on the back of the gauge and push the gauge out of the control panel
fascia. Carefully withdraw the capillaries through the grommet in the back of the control box.
6 Push in a replacement gauge, ensuring it is the correct way round, secure the sensor in place with union
and position the temperature phial in the pocket.
7 Re-assemble in reverse order, ensuring the front return edge of the control box top is located under the
front panel return.
8 Fill the boiler and re-pressurise the system to between 0.8 and 1.5 bar (to match the original system
pressure) as described in section 4.2, paragraphs 2 to 7. Set the adjustable pointer on the pressure
gauge to the system design pressure.
9 Test the boiler as described in section 7.5, paragraphs 1,2 and 3.
9.19 SAFETY VALVE
The safety valve is positioned at the back of the boiler to the left of the gas valve.
1 Ensure that the electricity supply has been isolated.
2 Drain the central heating circuit of the boiler as described in section 8.
3 Disconnect the discharge pipe from the safety valve.
4 Remove the union nut securing the pressure sensor to the front of the safety valve and withdraw the
sensor.
5 Unscrew the safety valve from the central heating flow pipe.
6 Re-assemble in reverse order using a new valve.
7 Fill the boiler and re-pressurise the system to between 0.8 and 1.5 bar (to match the original system
pressure) as described in section 4.2, paragraphs 2 to 7. Turn the safety valve knob a couple of times to
check that it re-seats properly without leaking. Re-pressurise the system if necessary.
8 Test the boiler as described in section 7.5, paragraphs 1,2 and 3.
9.20 PUMP or NON RETURN VALVE
Both the primary water (R/H) and central heating (L/H) pumps are the same. A replacement pump must
be set at setting 3.
A non return valve is fitted directly beneath each pump.
1 Ensure that the electricity supply has been isolated.
2 Drain the hot water or central heating circuit of the boiler as described in section 8.
3 Disconnect the pump wiring connector.
4 Undo the pipe unions from the pump and withdraw the pump. Remove the non return valve if it is to be
replaced.
Note: To gain access to the lower pump union it may be necessary to raise the control box as follows:-
Remove the four screws securing the control box top cover. Slide the cover back and up to remove it from
the control box. From inside the control box remove the four screws securing the box to the boiler.
5 Re-assemble in reverse order using a new pump with new seals or new non return valve. Ensure the
pump is fitted the correct way up - the direction of flow is upwards.
6 Open the mains water supply valve to refill the storage tank and vent the circuit by opening the hot taps,
or fill the boiler and re-pressurise the system to between 0.8 and 1.5 bar (to match the original system
pressure) as described in section 4.2, paragraphs 2 to 7.
7 Test the boiler as described in section 7.5, paragraphs 1,2 and 3.