Honeywell CM727 User Manual page 15

TROUBLESHOOTING THE CM727
Symptom
Blank Display (Power Loss).
Display shows flashing
symbol.
Display shows symbol.
Display shows the word 'SERVICE'
BDR91 red LED is constantly on
or flashing
Remedy
Check batteries are installed by removing the battery
cover.
Check batteries have been installed in the correct
orientation.
Replace the batteries.
The batteries in the thermostat are low on power
- Replace the batteries.
A fault has occurred in your heating system. Remove
and re-insert the batteries.
If the symbol does not clear after a few minutes
contact your installer.
Your installer has set a scheduled maintenance alert
period on your CM727 as a recommendation that your
heating system should receive a routine inspection.
Call your installer to arrange a maintenance visit.
Note: The CM727 and heating system will continue to
operate as normal.
RF communication lost due to the wrong location of
the room unit - Hook the room unit back on the wall
bracket where RF communication was reliable.
Call installer
NOTE: You can control the boiler manually when the
RF communication is lost: Press the BDR91 push
button to switch the boiler on and off. When the green
LED is on – the boiler is on.
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