Technical data
Installation and Operation manual ETHOS 36C and ETHOS 54C –1511/05-issue1
Page 26
6.2 Table of solutions
1. Check or replace the cable; check the connection on the terminal block.
2. Replace room thermostat or cable: check if the proper thermostat is installed.
3. Replace sensor or locate error in cable.
4. Try to loosen the pump shaft or replace pump drive.
5. Add water and locate leak; also check the expansion tank for internal leaks.
6. Too much water added, check expansion tank pressure or replace expansion tank.
7. Install plug: plug section with cables at fan side.
8. Clean fan blades.
9. Replace fan.
10. Turn on gas tap.
11. Check pipe and gas meter; if necessary, make a resistance calculation.
12. Modify gas pipe.
13. Install code key, check if code key is connected properly
14. Replace fuse; check all 230 V connections: pump, three-way valve, fan, PCB connection
15. Reset burner control unit by pressing the Info button
16. See section 5.8.1 Max. heat input setting
17. Check wiring by using wiring diagram; check its connection to the gas valve; check for moisture.
18. Check the cable for short circuits or overheating close to the steel plate; check spark plug cap for cracks and
replace cap, if necessary.
19. Replace burner control unit.
20. Moisture inclusion, check if cables sleeves are inserted properly into connector; check cable sleeve position and
rectify, before connector is inserted.
21. Check if connector(s) are pressed together with the right amount of pressure.
22. Open the flush pipe (left side of the appliance) by removing the sediment strainer; hold a container or bucket
under the pipe to collect the water. Use a pin to puncture the pipe to the upper left and upper right. If necessary,
remove the burner unit from the appliance and pour water into the heat exchanger to flush the siphon.
23. Not only bleed the boiler, but also the entire installation. Pull the appliance's 230V plug from the socket for this
type of bleeding, because the central heating pump should be switched off for bleeding.
24. Inspect the shut-off valve of the three-way valve by removing the pump motor with the 4 mounting screws. The
valve can be inspected from the inside of the pump housing.
The drive motor can be disassembled by removing the mounting screw at the front of the housing (lower right)
and then pressing the clicking lip at the side of the housing, just above the motor, and at the same time pushing
the motor downwards.
25. Check if the supply/discharge pipe is clogged.
26. Check discharge and supply system.
27. Check discharge and supply system.
28. Loosen the cold water connection of the appliance; remove the flow adjusting cock and clean it.
29. It is recommendable to first remove the burner control unit from the appliance to avoid water damage to the
printed circuit board. After draining the appliance, the T-piece couplings in the supply pipe and the flat coupling
of the return pipe at the pump must be removed.
Remove the earth cable, the spark plug cable and the high limit thermostat wires (upper right).
Loosen the 3 clamp-screws holding the heat exchanger. Pull heat exchanger partly forward and disconnect the
fan plug.
30. Replace limit thermostat by unscrewing it from the brass connector. System doesn’t need to be drained. ( Note,
do not remove brass adaptor )
31. Adjust according to par 5.5.1 Max. CH supply temperature or 5.5.2 Max. CH heat output
34. Remove the burner control unit with housing from the appliance by:
a. Removing the cover
b. Removing the wiring on the PCB connectors.
Then remove the display cable from the PCB and remove the burner control unit from the housing and replace
it.
35. Replace or bend. Always bend the electrode near the burner plate or else it might break.
36. If necessary, dry with hot air (blow-dryer) and check if it functions properly. If not, replace.
37. See 36.
38. See 36.
39. See 36. Remove the connection and dry it by blowing and/or using a blow dryer.
Table 12 Solutions to failures