Troubleshooting Guide - Honeywell ST9100C User Manual

Troubleshooting Guide

This is a quick guide to help you diagnose and cope with possible problems with
ST9100C. For further assistance, please contact your Installer.
Symptom
ST9100C has a blank
LCD display
ST9100C indicates
that the system is
ON, but radiators
are cold and/or taps
are running with cold
water.
ST9100C shows the
message 'INTERNAL
FAULT'
FAQ AND TrOUBLeSHOOTING
Possible Cause
No power to the
system
Fault in ST9100C
Temperature controls
are switched off or set
too low
Boiler or other
system controls have
malfunctioned
Fault in ST9100C
remedy
Check that there is power to the
system
Call Installer
Check that the temperature controls
in the system are set to appropriate
levels
Call Installer
Call Installer
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