Heat Engine Renewal - IDEAL LOGIC + Combi 24 Installation And Servicing

73 NO FLOW ThERMIsTOR REpLACEMENT
1. Refer to Frame 49.
2. Drain down the boiler. Refer to Frame 63.
3. Unplug the electrical lead.
4. Unscrew the thermistor (to facilitate removal a
13mm socket spanner should be used).
5. Fit the new thermistor using the sealing washer
provided.
6. Reassemble in the reverse order.
7. Refill the boiler. Refer to Frame 29.
8. Check the operation of the boiler. Refer to Frames
37-40.

74 hEAT ENgINE RENEWAL

Refer also to Frame 6 - 'Boiler Exploded View'
IMpORTANT
Before starting the removal procedure, protect the gas and
electrical controls with a waterproof sheet or plastic bag.
1. Refer to Frame 49.
2. Drain the boiler. Refer to Frame 63.
3. Remove the fan / venturi assembly and place on one side.
Refer to frame 50.
4. Remove the burner and place on one side. Refer to Frame
52.
5. Remove the ignition and detection electrodes and divertor
actuator head. Refer to Frames 54, 55 and 58.
6. Remove the spark generator. Refer to Frame 56.
7. Remove the gas valve. Refer to Frame 57.
8. Remove the expansion vessel. Refer to Frame 75.
9. Remove the no flow thermistor. Refer to Frame 73.
10. Remove the 2 M5 screws retaining the gas valve mounting
bracket and transfer bracket to the new heat exchanger.
11. Undo the inlet pipe union nut and remove the retaining spring
clip and remove pipe.
12. Undo the flow pipe union nut and remove pipe.
13. Remove the condensate rubber pipe. Refer to Frame 59, no. 2.
14. Remove the two heat exchanger fixing screws.
15. Remove the Heat exchanger.
16. Reassemble in reverse order, ensuring the heat exchanger
LH retaining bracket is correctly positioned. Replace any
new 'o' rings supplied with new heat exchanger and replacing
gaskets or seals if any sign of damage is evident. When
replacing the spring clips located on both the flow and return
pipe connections, ensure clip is oriented to correctly match
connecting pipe diameters.
54
sERVICINg
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4
17. Ensure the trap/siphon is filled with water. Refer to
Frame 59.
18. Refill the boiler. Refer to Frame 29.
19. Check operation of the boiler. Refer to Frames 37-40.
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Ideal Logic
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Combi -
Installation and Servicing
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