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WHAT IS A PROGRAMMER?
General Description
Your Honeywell ST9500C provides timing control for 2 zones within your central
heating system, letting you set ON and OFF periods to suit your own lifestyle.
The ST9500C does not directly control the temperature but works together with other
temperature controls, such as room thermostats, to control your heating system in
your home. It is common to set the living area as zone 1, and the bedroom area as
zone 2.
With 7-day programming and up to 3 on/off periods per day, every day can be set
differently, and each zone can be set to come on at different times from each other.
The following instructions explain how to programme and use the ST9500C 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 are in each zone. These are the times you should
use as the basis for the programmes. It will be necessary to allow some heat-up time
for the heating system after periods when it has been off – this would typically be 1
- 1½ hours, depending on your house and your preferences.
Other features are commonly available on the Programmer to enhance comfort and
convenience, for example, OVERRIDE, EXTRA HOUR, and MODE buttons.
A typical use of the OVERRIDE feature is when you return home unexpectedly for
the rest of the day and the heating is off. Just press the 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 to remember 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 was 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 each zone
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.
