Lcd Backlight; Low-Battery Detection; Battery Replacement - Horstmann T105NP Instruction Manual

LCD Backlight:

• LCD backlight is activated when BL or any key is
pressed. The backlight will automatically switch off
after 5 seconds if no other button is pressed.
• LCD backlight will not operate when battery is low.
• LCD backlight is illuminated throughout the Clock,
Program, and Temporary Override Temperature
settings.

Low-Battery Detection:

• Battery voltage is sampled every minute. When the
battery voltage drops to a certain level, the Low-
Battery warning indicator appears.
The thermostat functions
normally during battery low.
However, user must change the
batteries as soon as possible
before the battery is too weak
that normal operation cannot
be assured.
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BATTERY REPLACEMENT

It is recommended to replace the batteries when the
display is showing the battery-low icon. To replace
the battery,
1. Turn off the power of the Receiver first.
2. Remove the back housing (as illustrated on Page 10)
3. Replace the old batteries with 2 new AA alkaline
batteries.
4. Replace the back housing and stand.
5. Press the reset button once and then turn on the
power switch of the Receiver.
POWER SWITCH
There is a power switch on the Receiver. When there
is no demand to turn on the heating/cooling device,
e.g. when you go on holiday, it is recommended to
turn the power switch to the Off position.
LED INDICATOR
There are two LED's on the Power Control Unit as
status indicators:
1. The Red LED Illuminates when the unit is receiving
A 230V AC feed and the power switch is in the On
Position.
2. The Green LED Illuminates up on receiving a call
signal from the Control Centre to indicate the heating/
cooling device is energised.
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