d- If there is no loose contact in the cables and the resistance of the resistors are within normal
values, take measurements from other resistors in the same group. If all the resistors in a single
resistor group are dead, check that the relay trigger cables are undamaged and connected to both
the mainboard and relay board sides. On the mainboard, these cables should be connected to the
following ports:
- For 6 and 9 kW devices: "Relay Group 1"
- For 12 and 15 kW devices: "Relay Group 1" and "Relay Group 2",
- For 18, 24 and 27 kW devices: "Relay Group 1", "Relay Group 2" and "Relay Group 3".
e- If the connections are correct, disconnect the input electricity supply of the device from the Circuit
Breaker, disconnect the dead resistor cables from the relay boards and unplug them, and turn on the
Circuit Breaker again and put the device into test mode with K3 and K5. While the device is in test
mode, measure the resistance between the pins you disconnected. If you're reading a resistance
close to 0 between the relay pins, the relay board and mainboard are steady.
f- If you see the open-circuit ("OL") value between the relay pins, look at the LEDs on the relay
board and check if the lamps are lit.
g- If the lamps are on and "OL" (open-circuit) is still displayed on the screen, replace the relay
board.
h- If the trigger cable is properly connected but the LED lamp does not light, plug the trigger cable
into the port of another relay board and recheck the LED lamps.
- If the lamps of new relay board light, the problem will be solved by replacing the relay board.
- If the LEDs of the new relay board do not light, replace the mainboard.
- Put the device in test mode after the part replacements, and check if the resistors are activated.
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