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lock-out condition.
A unit that is locked out can be unlocked using any
one of the following methods:
• Remove mains power from the unit for at least
3 seconds, then restore power.
• Issue an ‘unlock’ command via Modbus RTU serial
communications.
• Reset the controller via Modbus RTU serial
communications.
If a unit has locked out and has been unlocked twice,
then locks out for a third time without having
managed at least once to stop once under normal
control, then the controller will no longer allow the
unit to be unlocked by the method described.
The controller display will show the message
"Lockout".
If this has happened the following steps must be
taken to unlock the unit:
i) Remove power, then restore power.
ii) Press push button SW3 on the controller.
iii) Start the unit heating as normal.
iv) Stop the unit by means of a normal off-command
(e.g. via the thermostat, remote on/off signal or
Modbus control).
Ensure the unit does not stop on yet another trip by
identifying and remedying the cause of the fault.
Refer to Temperzone (page 6) if assistance is
required.
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