ICI Caldaie RIO 140, Installation And Servicing Manual

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9 REPLACEMENT OF COMPONENTS
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5 Fit a replacement sensor, using a small amount of thread sealant.
6 Reconnect the electrical leads (polarity is not important) and re-assemble in reverse order.
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.
8 Test the boiler as described in section 7.5, paragraphs 1,2 and 3.
9.28 MAIN HEAT EXCHANGER
Take care when handling the new heat exchanger not to damage the fins.
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 eight screws securing the inner case front panel and remove the panel, take care not to
damage the seal.
4 Remove the six screws securing the combustion chamber front cover and remove the cover.
5 Disconnect the flue elbow from the flue and remove it from the top of the boiler
6 Remove the six screws securing the top of the sealed chamber and remove, take care not to damage the
seal.
7 Disconnect the air pressure switch sensing tubes from the fan noting their position.
8 Disconnect the electrical leads from the fan motor, noting their position.
9 Remove the remaining two screws (behind the flue hood) securing the flue hood to the combustion
chamber. Lift up the fan and flue hood assembly to clear the heat exchanger and remove from the boiler.
10 Disconnect the electrical leads from the central heating thermostat (left hand side of the heat exchanger)
and unclip the overheat thermostat bulb (on the right hand side of the heat exchanger).
11 Undo the small socket head grub screws, securing the heat exchanger to the inlet/outlet pipes, by about 3
turns.
12 Lift the right hand side of the heat exchanger up to clear the inlet pipe then withdraw it from the outlet
pipe.
13 Transfer the central heating sensor and overheat thermostat bulb clip from the old heat exchanger to the
new one.
14 Re-assemble in reverse order using new 'O' rings on the heat exchanger connections, ensuring the grub
screws are correctly located and not over tightened. Also replace the flue seals and the seals to the boiler
top cover if necessary.
Note: When reconnecting the air pressure switch sensing tubes to the fan connect the right (transparent)
tube to the upper connector (nearest the fan outlet) and the left (pink) tube to the lower connector.
15 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.
16 Test the boiler as described in section 7.5, paragraphs 1,2 and 3.
9.29 COMBUSTION CHAMBER INSULATION PANELS
Refer to Health and Safety Information on page 2 and dampen the panels before carrying out any work on
them.
1 Ensure that the electricity supply has been isolated.
2 Remove the main heat exchanger as described in section 9.28, paragraphs 2 to 9.
3 Remove the rear panel by carefully pulling it forward at the top and lifting out.
Remove the front and side panels in a similar way.
4 Insert the new panels bottom first then push back into position.
5 Re-assemble in reverse order, ensuring the heat exchanger retaining screws are correctly located and
not over tightened.
Note: Ensure the seals on the sealed chamber top and front panels are intact and in position, and when
reconnecting the air pressure switch sensing tubes to the fan connect the right (transparent) tube to the
upper connector (nearest the fan outlet) and the left (pink) tube to the lower connector.
6 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.
8 Test the boiler as described in section 7.5, paragraphs 1,2 and 3.