Troubleshooting Guide - Honeywell ST9500C User Manual

Troubleshooting Guide

This is a quick guide to help you diagnose and cope with possible problems with
ST9500C. For further assistance, please contact your Installer.
Symptom
ST9500C has a blank
LCD display
ST9500C indicates
that Zone 1 and/or
Zone 2 are ON, but
radiators are cold and/
or taps are running
with cold water.
ST9500C shows the
message 'INTERNAL
FAULT'
FAQ AND TROUBLESHOOTING
Possible Cause
No power to the
heating system
Fault in ST9500C
Temperature controls
are switched off or set
too low
Boiler or other
system controls have
malfunctioned
Fault in ST9500C
Remedy
Check that there is power to the
heating system
Call Installer
Check that the temperature controls
in the system are set to appropriate
levels
Call Installer
Call Installer
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