Checking The Non-Return Valve - DeDietrich EVODENS PRO Amc 45 Service Manual

8 Maintenance
Fig.138 Cleaning the heat exchanger
8
10
12
Fig.139 Disconnecting the fan
3
5
1
40 AMC Pro
8. Use a vacuum cleaner fitted with a special endpiece (accessory) to
clean the top part of the heat exchanger (combustion chamber).
9
9. Vacuum again without the top brush on the end piece.
10. Clean the lower section of the heat exchanger with the special
cleaning blade (accessory).
11. Check (e.g. using a mirror) whether any visible contamination has
been left behind. If it has, remove it with the vacuum cleaner.
12. Check that the burner cover of the dismantled burner is free from
cracks and/or damage. If not, replace the burner.
11
13. Reassemble the unit in reverse order.
14. Open the gas supply and switch the power supply to the boiler back
on.
AD-3001180-01
8.3.7
1. Remove the air inlet pipe from the venturi.
2. Unscrew the gland of the gas valve unit.
3. Disconnect the fan plugs (on the front and rear).
4. Remove the screwed-on plug from the gas valve unit.
4
5. Remove the ignition electrode plug from the ignition transformer.
2
AD-3001178-01
Servicing the burner is usually not necessary, it is self-cleaning. Use
compressed air to carefully blow away any dust.
Caution
Remember to reconnect the fan plug.
Check that the gasket is correctly positioned between the mixing
elbow and the heat exchanger (the gasket must lie absolutely
flat in the appropriate groove to ensure that no gas can leak).
Tighten the gland on the gas valve unit with a torque wrench to
the firmness of 27,5 Nm.
Tighten the front plate nuts with a torque wrench to the firmness
of 10 Nm.

Checking the non-return valve

7725106 - v.01 - 05062019