Fine Tuning Your St9420C; Changing From Am/Pm Time Display To The 24 Hour Clock; Changing The Installer Parameters - Honeywell Y9420S User Manual

Changing from AM/PM Time Display to the 24 Hour Clock

Your ST9420C can operate on the 12 hour AM/PM or 24 hour clock formats. To
change the format, ensure the slider is in the RUN position then press and hold the
and buttons together for about 2 seconds. Ignore the 'NOT VALID' message
that will appear briefly. Then the displayed times will be changed automatically to
the new format.
Repeating this procedure will change the clock display back to the original format.

Changing the Installer Parameters

The ST9420C has a special Installer Mode where some features can be adjusted
to suit your lifestyle or preferences – these are called Installer Parameters, and are
listed in the table below, along with a description of the options that are possible.
Your installer should set this up for you to suit your application (see CONFIGURATION
& SERVICE DATA section). However, you may wish to alter some of the settings
yourself, and this section shows you how to do this.
Note: some parameters indicated by * may only be viewed if the previous parameter
is set to a particular value.
INSTALLER
PARAMETER
24hr or am/pm
clock display.
Configure backlight
operation.
Enable/disable auto
time change.
1-day or 5/2-day or
7-day operation.
Number of ON/OFFs
per day.
Select default time
programme.
Set hot water
temperature
Parameter Default
Number Value
1 12
2 2
3 1
4 7
5 3
6 A
8 60°C

FINE TUNING YOUR ST9420C

Options Description
12, 24 12 = am/pm display
24 = 24hr display
0, 1, 2 0 = off
1 = on if button pressed
2 = on continuously
0, 1 0 = disabled
1 = enabled
1, 5, 7 1 = 1-day operation
5 = 5/2-day operation
7 = 7-day operation
2, 3 2 = 2 on/offs per day
3 = 3 on/offs per day
A, b, C A = standard
b = at home
C = economy
40 to Stored hot water set
85°C temperature
15