Nibe VVM 500 - Troubleshooting Guide

Troubleshooting guide
Alarm 1 - sensor fault
Is the actual sensor correctly
connected?
YES
YES
YES
Are the characteristics for the
sensor OK, measured from any
external joint in the sensor cable?
(See "Data for temperature
sensor" section.)
Is any external joint in the sensor
cable correctly connected?
Defective sensor. Replace.
NO
NO
Action.
Are the characteristics for the
sensor OK, measured from
connected sensor cable on the
input card (AA3)?JSH (See "Data
for temperature sensor" section.)
Action.
NO
Check wiring and switches.
NO
Is the output voltage from the card
correct? (See "Data for
temperature sensor" section.)
Defective input circuit board
(AA3). Replace.
YES
Check wiring and switches.
NO
YES
23Chapter 6 | TroubleshootingNIBE™ VVM 500