Electrical System - Fujitsu WATERSTAGE 112 Maintenance Document

Heat Pump, Split System, Single Service, 3 phase

5.1.2 Electrical System

Outdoor Unit Overvoltage
Check for possible causes in the list below (this list is
not exhaustive):
•
Problem with the compressor
•
PFC board
•
Inverter board
•
Main board
•
Faulty power relay
Inspection of the Power Transistor Module (Inverter board)
Disconnect the compressor relay and the condenser
connection. Measure the resistance value at the
points shown on the illustration, and then compare
the values observed with those in the table.
Multimeter
Maintenance Document 1394-1
Resistor
1 MOhm
or more
Steps to be followed before performing any work
on the Inverter module:
•
First switch off the system using the circuit
breaker at the head of the line.
•
Remove the unit cover and then remove the
Inverter module cover.
•
Measure the voltage at the condenser terminals.
You should find a value of 5 Vdc or less.
Terminal block
59