TFC Group HWPRS User Manual

Page 4

Additional functions:

Frost protection: Whilst in the normal running mode, press and hold the button for 3
seconds to activate Frost Protection. The frost protection indicator shown in the illustration will
flash. While frost protection is activated, the temperature set-point is 5

C. In frost protection

mode it is not possible to override the 5

C temperature setting. To turn frost protection off, press

and hold the button for 3 seconds. The frost protection indicator will disappear from the
display, and normal running mode is restored.

Review temperature setting: Briefly press the up or down arrow button. The blue backlight will operate, and the
current temperature setting will be displayed (flashing). In frost protection mode, the LCD will show 5

C. If the

device is in temporary override mode (see next function), the LCD will show the temporary set-point temperature.

Temporary override (temperature adjustment): Press the up or down arrow buttons to temporarily adjust the
temperature setting: press and hold the up or down arrow button for 2 seconds. The display will show the existing
temperature setting (flashing), and then the temperature value will scroll up or down. Keep the button pressed to
scroll rapidly, or press the button repeatedly to adjust the temperature 0.5

C at a time. Release the button when

the new temperature is reached. The display will continue flashing for 3 — 4 seconds, and then time-out to once
again show the existing room temperature. Temporary override remains active until the next timed program is
reached.

LCD backlight: The blue backlight is activated when any button is pressed, and will automatically turn off after 5
seconds. The LCD backlight will not operate when the battery is low.

Low battery warning: When the battery voltage drops below a critical level, the low-battery warning indicator will
be displayed. You should renew the batteries as soon as possible. If low batteries are left in the device, it will
eventually be unable to switch the heating on or off. The transmitter has a capacitive memory which maintains
the time and all other settings for up to one minute. If the batteries are not replaced within one minute, the trans-
mitter will have to be re-programmed.

Sleep mode: Press and hold the up and down arrow buttons simultaneously for 3 seconds to activate sleep
mode. All functions will be paused, saving battery power. The output will be turned off immediately. The clock
will continue running. The display will show just time and weekday. Press any key to de-activate sleep mode,
and restore normal running mode.

Specification:

Battery powered 2 x AA (LR6) alkaline

LCD display

Blue backlight

Time display 12 hour am / pm

Time accuracy: ± 1 min / month

Operating Control range: 10—35

C in 0.5

C steps.

Temperature control differential: 0.5

Frost protection temperature: 5.0

Relay output: Volt-free 3A (resistive)