USER GUIDE
TO BE LEFT
WITH USER
ST6400A
Programmer
42009084-006 R1
INTRODUCTION
The ST6400A programmer controls your central
heating system. It will enable you to select the
times when heating and hot water are switched
ON
and
OFF
.
FEATURES
•
24 hour heating programme.
•
24 hour hot water programme.
•
Two
ON/OFF
switching times per day.
•
Built-in programme with typical
ON/OFF
times.
•
Override buttons for heating and hot water.
•
Extra hour buttons for heating and hot water.
•
Built-in battery to prevent loss of programme
during power cuts.
•
12 hour am/pm or 24 hour clock format.
The ST6400A and other Honeywell controls in
your central heating system will provide comfort-
able temperatures in your home when you want
them.
12 HOUR AM/PM or 24 HOUR CLOCK DISPLAY
Your programmer can operate on 12 hour am/pm
or 24 hour clock formats. To change the format,
ensure the setting slider is in the
RUN PRO-
GRAMME
position then press the
+
and
-
buttons
together for about 5 seconds. All the displayed
times will be automatically changed to the new
format.
Repeating this procedure will change the clock
display back to the original format.
OPERATING YOUR CONTROLLER
For normal operation the setting slider must be in
the
RUN PROGRAMME
position.
A red indicator lamp shows when the heating or
hot water is switched
ON
.
Two sliders are provided to select how the heat-
ing and hot water are controlled.
The
HEATING SLIDER
has four positions:
OFF -
The Heating will remain
OFF
.
AUTO -
The heating will be switched
ON
and
OFF
automatically according to the heating
programme.
ONCE -
The heating will come
ON
at the first
programmed
ON
time and go
OFF
at the last
programmed
OFF
time.
CONT. -
The heating will remain
ON
continu-
ously.
The
HOT WATER
slider operates in the same
manner as described above for the
HEATING
SLIDER
.
EXTRA HOUR
The
EXTRA HOUR
buttons switch the heating or
hot water
ON
for up to 3 extra hours without alter-
ing the programme. Pressing either button once
will give one extra hour, and the words
HEATING
+1 HR
or
HOT WATER +1 HR
show on the dis-
play to confirm the button has been pressed.
When the red indicator lamp is
OFF
, pressing the
EXTRA HOUR
button switches the heating or hot
water
ON
for just one hour.
When the red indicator lamp is
ON
, pressing the
EXTRA HOUR
button extends the programmed
ON
period by one hour.
Further presses of the
EXTRA HOUR
buttons will
increase the extra hour period by one hour for
each button press, up to a maximum of 3 hours.
The display will change to show the number of
extra hours, for example
H3 HR
or
HOT
WATER +2 HR
.
To cancel the extra hours, keep pressing the
EXTRA HOUR
button until the
H (1,2
or 3) HR
or
HOT WATER + (1,2 or 3) HR
disap-
pears from the display.
OVERRIDE
The
OVERRIDE
buttons switch the heating or
hot water
ON
or
OFF
without altering the pro-
gramme.
When the indicator lamp is
ON
, pressing the
OVERRIDE
button switches the heating or hot
water
OFF
until the next programmed
ON
time.
When the indicator lamp is
OFF
, pressing the
OVERRIDE
button switches the heating or hot
water
ON
until the next programmed
OFF
time.
RESET
To reset the programmer back to the original
built-in programme press the
RESET
button with
the tip of a pen or pencil.
POWER FAILURE
Your programmer has a built-in battery to ensure
correct operation after a main supply power cut.
No action should be necessary following a power
cut of up to 4 days. Longer power cuts may
require you to re-programme.
