GRUNDKORT MCB RES.D Part Number 818231 main control board (MCB) used in several NIBE heat pump systems. This is an electronics module, typically installed inside the indoor unit.

GRUNDKORT MCB RES.D
•     Type: Main Control Board (MCB)
•     Brand: NIBE
•     Part Number 818231
•     Controls system logic, sensors, compressor communication, and safety functions
•     Acts as the “brain” of the heat pump

Original control board has failed due to:
•     Power surges
•     Moisture ingress
•     Component burnout
•     Firmware corruption

Compatible NIBE Units
While compatibility varies by production year, this MCB type is commonly associated with:
•     NIBE S series
•     NIBE VVM & SVM indoor modules
•     NIBE S-series heat pumps ( new generation ) S325, S735, S1155, S1156, S1255 & S1256

Important notice: Base Card 818231 CAN NOT be taken out of one unit to another. The part has to be NEW.