General
Description
Your
Honeywell
ST9400C
provides timing control for both your central heating and
hot water systems, letting you set ON and OFF periods to suit your own lifestyle.
. . .
The ST9400C does not directly control the temperature butworks togetherwith other
temper~ture
controls, such as room thermostats and cylinder thermostats,
to
control
your heating and hot water system
in
your home.
With 7-day programming and up to 3 on/off periods per day,
ev-ery
day can be set
differen.tly, and heating and hot·water can be set at different times from each other.
The following instructions explain how to programme and use the ST9400C to
provide the most home comfort at the least cost.
The
way
to use a Programmer
Think about the time periods when you are typically in the house and when you are
not, and also the times when you use a lot of hot water. These are
~he
times you
should use as the basis for the programmes. It will be necessary
to
altow some
heat-up time for the heating system after periods when it has been off -this would
typically be 1 - 1
Y2
hours, depending on your house and your preferences.
Other features are commonly available on the Programmerto enhance comfort and
convenience, for example, OVERRIDE, EXTRA HOUR, and MODE buttons.
A typical use ofthe OVERRIDE feature is whenyou return home unexpectedlyforthe
rest of,the day and the
heating
is off. Just press the heating OVERRIDE button and
the heating will come on until the next programme time, at which point it will follow
the normal programme. The advantage here
·is
that you
do
not have toremember to
switch off because the normal time programme does this for you.
•
A typical use of the EXTRA HOUR·button would be if you returned to the house for
a short period when the heating and hot water were off. Pressing the appropriate
EXTRA HOUR button gives you
1,
2,
or 3 hours of heating, exactly when you need
it.
Another typical use is when the heating
is
already on and you want it to stay on a
little
longer-
just press EXTRA HOUR and, for that
day
only,
an
hour will be added
to the end of the time at which heating normally goes off.
The MODE buttons allow you to select how you want to operate heating and hot
water independently. The most obvious use is to switch heating OFF during the
summer months, but you may also use this feature if you take a mid-week day off
work, you can then set the MODE to ONCE to keep the system ON during the day
from the first programmed ON time till the last programmed OFF time.
