Control Of Your System; General Description Of Controls In Your System; The Way To Use A Programmer - Honeywell Y9520Z Sundial RF2 Pack 5 User Manual

CONTROL OF YOUR SYSTEM

General Description of Controls in Your System

Your Honeywell ST9520C provides timing control for both zones in your central
heating system, letting you set ON and OFF periods to suit your own lifestyle.
The ST9520C 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.
With 7-day programming and up to 3 on/off periods per day, every day can be set
differently, and both heating zones can be set at different times from each other.
ST9520C also has a Boiler Service reminder / Shut-down feature, which helps
ensure your gas boiler is regularly serviced in compliance with UK Gas Safety
Regulations. For more details see pages 18 & 19.
Your system includes DT92E wireless room thermostats and may include a BDR91T
Relay Box to switch your boiler remotely. These products use state of the art 2 way
RF communications to share information and give you robust and flexible control of
your indoor environment.
The following instructions explain how to programme and use the ST9520C, and
associated controls, 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 occupy each of the zones. 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.
If Optimum Start has been selected (see page 17), you do not have to allow for this
heat up time as the Programmer is intelligent and will calculate the correct starting
time for your house. This is based on measurements it makes about your system
characteristics, and on the current and target room temperatures. All you have to do
is programme the time periods when you want to be comfortable.
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 zone OVERRIDE button and
the heating will come on in that zone 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.
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