Honeywell Sundial RF Pack 3 Wireless Enabled Programmer and Thermostats User Manual

							User Guide
Y9420S Sundial RF2 Pack 3
How to use:
  ST9420C Wireless Enabled Programmer
  DT92E Wireless Room Thermostat
  CS92A Wireless Cylinder Thermostat
  BDR91T Wireless Enabled Relay Box (if installed) System Components
Energy Efficiency and the Environment
Home energy use is responsible for more than ¼ of the total UK carbon emissions 
which contribute to climate change. Heating and hot water systems based on 
boilers account for 
 of this figure, so it is important to understand how your 
controls can help to maximize energy efficiency while maintaining your comf\
ort.
Your Programmer should be used in conjunction with appropriate temperature 
controls. In order to save energy the following general points should be observed:
1.  Ensure your system contains a room thermostat and a hot water thermostat, 
and that both are set to appropriate temperature levels: typically 20°C for the 
room temperature and between 50 - 60°C for the hot water temperature.
2. 
Programme your heating and hot water to be off when you are not in the house. If 
you are concerned about possible frost damage to any exposed pipe work, it is 
advisable to fit a frost protection system – your installer can advise you about this.
3.  Think about how you use your domestic hot water – if you have a stora\
ge 
system, it is not necessary to have this switched on all the time, even when you 
are in the house.
4.  Consider the heat up times required for your central heating. Every home 
responds differently when the heating is switched on. Adjust the start time so 
that you are not cold when you get up in the morning. A shorter heat up time is 
required for other heating periods.
5.  In the evening, when the house is up to temperature, it is often possible to 
switch off the heating up to an hour before you go to bed, without any noticeable 
reduction in comfort.
This document is to be left with the user
and forms part of a Home Information Pack
This section is to be completed by the Installer
Honeywell Control Systems Ltd.
Arlington Business Park,
Bracknell
Berkshire
RG12 1EB
Technical Help Desk: 08457 678999
www.honeywelluk.com 50047645-008 A
© 2011 Honeywell International Inc.
PLEASE RESPECT YOUR ENVIRONMENT!
Take care to dispose of this product and any 
packaging or literature in an appropriate way
WHAT IS A PROGRAMMER?
...an Explanation for Householders (as recommended by the Energy Savings Trust)Programmers allow you to set ‘On’ and ‘Off’ time periods. Some models switch the central heating and 
domestic hot water on and off at the same time, while others allow the domestic hot water and heatin\
g to 
come on and go off at different times. Set the ‘On’ and ‘Off’ time periods to suit your own lifestyle. On some 
programmers you must also set whether you want the heating and hot water t\
o run continuously, run under 
the chosen ‘On’ and ‘Off’ heating periods, or be permanently off. The time on the programmer must be 
correct. Some types have to be adjusted in spring and autumn at the changes \
between Greenwich Mean 
Time and British Summer Time. You may be able to temporarily adjust the 
heating programme, for example, ‘Override’, ‘Advance’, or ‘Boost’\
. These 
are explained in the manufacturer’s instructions. The heating will not work 
if the room thermostat has switched the heating off. And, if you have a hot-
water cylinder, the water heating will not work if the cylinder thermostat 
detects that the hot water has reached the correct temperature.
WHAT IS A ROOM THERMOSTAT?
...an explanation for Householders (as recommended by the Energy Savings Trust)A room thermostat simply switches the heating system on and off as necessary. It works by sensing 
the air temperature, switching on the heating when the air temperature falls below the thermostat 
setting, and switching it off once this set temperature has been reached. Turning a room thermostat to 
a higher setting will not make the room heat up any faster. How quickly the room heats up depends on 
the design of the heating system, for example, the size of boiler and ra\
diators. Neither does the setting 
affect how quickly the room cools down. Turning a room thermostat to a lower setting will result in the 
room being controlled at a lower temperature, and saves energy. The heating system will not work if 
a time switch or programmer has switched it off. The way to set and use your room thermostat is to 
find the lowest temperature setting that you are comfortable with, and then leave it alone to do its job. 
The best way to do this is to set the room thermostat to a low temperature – say 18ºC – and then turn 
it up by one degree each day until you are comfortable with the temperature. You won’t have to adjust 
the thermostat further. Any adjustment above this setting will waste energy and cost you more money.
If your heating system is a boiler with radiators, there will usually be only one room thermostat to 
control the whole house. But you can have different temperatures in individual rooms by installing 
thermostatic radiator valves (TRVs) on individual radiators. If you don’t have TRVs, you should choose 
a temperature that is reasonable for the whole house. If you do have TRVs, you can choose a slightly 
higher setting to make sure that even the coldest room is comfortable, then prevent any overheating 
in other rooms by adjusting the TRVs.
Room thermostats need a free flow of air to sense the temperature, so they must not be covered by 
curtains or blocked by furniture. Nearby electric fires, televisions, wall or table lamps may prevent the 
thermostat from working properly.
Location
ST9420C
DT92E
(typically in living room or hallway)
CS92A
(typically next to hot water tank, in bedroom)
BDR91T
(If installed, typically next to boiler) 
						

							HOT WATERHEATING
EXTRA HOUR
OVERRIDE EXTRA HOUR
OVERRIDE
NEXT
D AY
COPY
D AY
HOLIDAY
OK
NEXT DAY/TIME
HOT WATER HEATING RUN
Hot Water ‘ON’ period indicator
Time Display
LoT™ Technology Display
Programme Time Markers
Day of Week Indicator
RF Symbol
Heating ‘ON’ period indicator
Heating Extra Hour Button
Heating Indicator Lamp
Heating Override Button
Boiler Status Indicator
Slider
ECO Mode Active
Frost Protect Indicator
ECO Countdown Indicator
Heating Demand Indicator
Setpoint Change Buttons
ECO Button
OFF/Standby Button
OFF/Standby Indicator
RF Communications Indicator
Battery Low Indicator
Fault Indicator
Setpoint Indicator
Temperature Display
Sensor element Transceiver
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15
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16
11
17
12
18
13
19
21
20
Heating Operating Mode Indicator
Heating Operating Mode Button
OK/Next Button
Clock – and + Buttons
Hot Water Operating Mode Button 
Hot Water Operating Mode Indicator
Holiday Button
Copy Day Button
Next Day Button
Hot Water Override Button
Hot Water Indicator Lamp
Hot Water Extra Hour Button
22
23
24
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35Keep this document in a Home Information Pack
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CS92A CONTROLS LAYOUT
DT92E CONTROLS LAYOUTST9420C CONTROLS LAYOUT
11
ST9420C
This product and its associated documentation and packaging are protected by various intellectual 
property rights belonging to Honeywell Inc. and its subsidiaries and existing under the laws of the UK 
and other countries. These intellectual and property rights may include patent applications, registered 
designs, unregistered designs, registered trade marks, unregistered trade marks and copyrights.
Honeywell reserves the right to modify this document, product and functionality without notice. This 
document replaces any previously issued instructions and is only applicable to the product(s) described.
This product has been designed for applications as described within this docume\
nt. For use outside of 
the scope as described herein, refer to Honeywell for guidance. Honeywell cannot be held responsible 
for misapplication of the product(s) described within this document.
Manufactured for and on behalf of the Environmental and Combustion Controls Division of Honeywell 
Technologies Sàrl, ACS-ECC EMEA, Z.A. La Pièce 16, 1180 Rolle, Swit\
zerland by its Authorised 
Representative Honeywell Inc.
CONFIGURATION & SERVICE DATA
Boiler & System Service Log
The space below can be used to provide a record of boiler & system services and 
the names and contact numbers of the Installer and Service Personnel.
This information is important for a Home Information Pack.
Service/Installation 
DateInstallation/Service 
Engineer Telephone Number / 
Contact Details
Configurable Features
OptionsFactory 
settingInstaller configured 
(note value)
DT92E Configuration
Measurement offset -3.0°C to 0 to 3.0°C0
Upper setpoint limit 21 to 35°C35°C
Lower setpoint limit 5 to 21°C5°C
Energy saving ECO setpoint 5 to 35°C18°C
Green light 
(under button)
Button
Red light 
(under button) 
						

							3
Contents
CONTROL OF YOUR SYSTEM
 General Description of Controls in Your System ................................................... 4
  The way to use a Programmer ........................................................................\
...... 4
  The way to use a Room Thermostat / Control of Your Boiler / Optimisation  .........5
GETTING STARTED WITH YOUR ST9420C
  Step 1: Setting the Date & Time ........................................................................\
.... 6
  Step 2: Running a Built-in Programme ................................................................. 7
PROGRAMMING YOUR  ST9420C
  The Built-in Programmes / Your Personal Programme .......................................... 8
  Reviewing the Programme Times / Modifying the Hot Water Programme  ............9
  Modifying the Heating Programme / Disabling or Enabling Time Periods ......... 11
OPERATING YOUR  ST9420C
  Choosing the Operating Mode ........................................................................\
... 12
  Overriding the Operation Without Changing the Programmes  ...........................12
  The Extra Hour Function / The Holiday Function ................................................ 13
  Enquiry Mode ........................................................................\
............................. 14
FINE TUNING YOUR  ST9420C
  Changing from AM/PM Time Display to the 24 Hour Clock  ................................15
  Changing the Installer Parameters ..................................................................... 15
 Optimisation ........................................................................\
................................ 17
  How to set your Hot Water Set Temperature ....................................................... 18
BOILER SERVICE REMINDER
  Countdown to Service / When Service is Due .................................................... 18
 Shut-down ........................................................................\
................................... 19
OPERATING YOUR  DT92E
  Inquiring about the Set Temperature / Adjusting the Set Temperature ............... 19
  Switching Off / Display Updates / Heating Indicator / Frost Protection  ..............20
DT92E OPERATING INDICATORS
 
Low Battery Indicator / Battery Replacement / RF Communications Indicator / Lockout ... 21
DT92E ENERGY SAVING ECO FEATURE
  Entering ECO Mode and Setting the Energy Saving Time Period  ......................22
  What Happens in ECO Mode? ........................................................................\
.... 22
  How to Exit ECO Mode ........................................................................\
............... 23
FINE TUNING YOUR  DT92E
  Changing the DT92E Installer Parameters ......................................................... 23
OPERATING YOUR CS92A HOT WATER THERMOSTAT
  Basic Operation / Battery Replacement / Error Indications  ................................25
OPERATING YOUR BDR91T RELAY BOX (IF INSTALLED)
  BDR91T Controls Layout / Automatic Operation ................................................ 26
  Temporary Manual Override / Loss of Wireless Communications  ......................26
FAQ  AND TROUBLESHOOTING
  Frequently Asked Questions ........................................................................\
....... 27
  Troubleshooting Guide ........................................................................\
................ 29
CONFIGURATION & SERVICE DATA
  Configuration Data (to be completed by Installer) ............................................. 34
  Boiler & System Service Log ........................................................................\
...... 35 
						

							4
General Description of Controls in Your System
Your Honeywell ST9420C 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 ST9420C does not directly control the temperature but works together with 
other temperature controls, such as room thermostats and cylinder thermostats or 
sensors, to control your heating and hot water system in your home.
With 7-day programming and up to 3 on/off periods per day, every day can be set 
differently, and heating and hot water can be set at different times from each other.
ST9420C 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 a DT92E wireless room thermostat 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 ST9420C, 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 use a lot of hot water. 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 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 to remember to 
switch off because the normal time programme does this for you.
CONTROL OF YOUR SYSTEM 
						

							5
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.
The way to use a Room Thermostat
The way to set and use your room thermostat is to find the lowest temperature setting 
that you are comfortable with, and then leave it alone to do its job. The best way to do 
this is to set the room thermostat to a low temperature – say 18°C – and then turn it 
up by one degree each day until you are comfortable with the temperature. You won’t 
have to adjust the thermostat further. Any adjustment above this setting will waste 
energy and cost you more money.
DT92E has a green ECO button, which enables you to set a period of time at a lower 
temperature. This energy saving feature is most useful if you are out of the house 
for a few hours, or if you want a reduced temperature for a while and don’t want to 
have to remember to turn the temperature back up (see pages 22 & 23 for details).
Control of Your Boiler
There are two ways your boiler may be controlled. It may be switched directly using 
the ST9420C timer, or, if installed in a remote location, it may be switched using a 
BDR91T relay box. 
In each situation the operation of the boiler is determined automatically by the 
combination of inputs from the room thermostat and the timer, and in such a way as 
to maintain your comfort with minimal energy use. The timer will indicate the on/off 
status of the boiler by showing the flame symbol 
.
Optimisation (see page 17 for explanatory diagrams)
Your control system has some features called Optimisation, which aim to save 
energy while making you as comfortable as possible. These may or may not be 
enabled – check page 34 where your Installer should have indicated how these 
were set. Optimisation does not apply to your Hot Water, only to your Heating.
Optimum Start works by measuring how quickly your system normally heats up, and 
CONTROL OF YOUR SYSTEM 
						

							6
Your ST9420C should have been set up to work correctly when it was installed. 
However, the following will show you how you can modify your settings to meet 
your particular lifestyle.
To assist you with programming and everyday use your ST9420C will display text 
messages at every stage to help you get the most out of your central heating and hot 
water system. The ST9420C uses LoT™ Technology to constantly update the display 
to give you feedback about what is required.
Step 1: Setting the Date & Time
Your ST9420C had the date and time set at the factory, and these are normally 
maintained by a backup battery in the event of power failures. If you wish to change 
the date or time, or if the LoT™ Display shows the message ‘SET DA\
TE + TIME’ just 
follow the instructions below. Otherwise, go to Step 2.
a. Move the slider to the DAY/TIME position. The message ‘SET DATE + TIME’ will 
show briefly on the screen, followed by ‘SET THE DAY’, and the day of the month 
will now be flashing to indicate it can be changed.
GETTING STARTED WITH YOUR ST9420C
HOT WATER HEATING
DAY/TIME
HOT WATER HEATING RUN
using this to calculate the correct time to switch on to reach your comfort temperature, 
when you want it. So the times you set are when you want the heating to be at 
the correct temperature, and the system adjusts the starting time to meet this.
Delayed Start is an alternative to Optimum Start. It works by using your normal 
programmed start times, compares the actual temperature with the set temperature, and 
delays the start a little depending on how close these temperatures are to each other.
Optimum Stop saves energy, and money, by switching off a little earlier than the 
normal programme time. If the house is up to temperature, you will not notice the 
effect on the temperature, but you will see a difference in your fuel bill.
The radiator symbol on ST9420C will flash to let you know whenever Opt\
imisation 
is operating. 
The other controls in your system should not require adjustment.
CONTROL OF YOUR SYSTEM 
						

							7
GETTING STARTED WITH YOUR ST9420C
b. To change the day of the month, press the   or  buttons until the correct 
day is shown.  Each press of the button will change the date by one day. As soon 
as a change has been made, the message ‘IS DAY OK?’ will be displayed. Once 
the correct day is reached, press the green 
 button to confirm, and move to 
the next step. If you do not need to make a change, just press the  button 
immediately and this will move you to the next step.
c.  The month digits will now be flashing and ‘SET THE MONTH’ will be displayed. To 
change the month, press the 
  or  buttons until the correct month is shown. 
The message ‘IS MONTH OK?’ will be displayed. Press the green  button to 
confirm the month is correct and move to the next step.
d.  The year digits will now be flashing and ‘SET THE YEAR’ will be displayed. To 
change the year, press the 
  or  buttons until the correct year is shown. The 
message ‘IS YEAR OK?’ will be displayed. Press the green  button to confirm 
the year is correct. If you have made a change and the date is a valid date, the 
message ‘DATE SAVED’ will show, and you can move to the next step. If the date 
you set was not valid, for example 31 September, the message ‘INVALID’ will 
show and you will be returned to the start of the date setting operation.
e.  The time will now be flashing and the message ‘SET THE TIME’ will be displayed. 
To change the time, press the 
  or  buttons until the correct time is shown. 
Each press of the button will change the time by one minute. Holding the button\
 
down for more than a few seconds will change the time slowly at first, then 
quickly. The message ‘IS TIME OK?’ will be displayed. Press the green 
 button 
to confirm the time is correct.  If you have made a change, the message ‘TIME 
SAVED’ will show, followed quickly by ‘DATE + TIME COMPLETE’.
f.   Move the slider to the RUN  position to complete setting the date and time.
Note: if the slider is moved at any time before the date and time have been set 
correctly, the message ‘DATE UNCHANGED’ will be displayed briefly, and your 
changes will not be saved.
Step 2: Running a Built-in Programme
With the date and time correct, your ST9420C Programmer will now be operating 
to the built-in programmes. These have been designed to provide heating and hot 
water at typical times throughout the day, but if you want to customise the settings, 
please see the next section ‘PROGRAMMING YOUR  ST9420C’ (page 8). 
						

							8
PROGRAMMING YOUR  ST9420C
The Built-in Programmes
The built-in programmes give you a starting point that you can personalise to your own 
requirements. Your Installer should have selected one and ticked the box alongside it. \
If there 
is no tick, the product normally leaves the factory with Profile A installed, but it is a simple 
matter to select one of the other profiles (see Changing the Installer Parameters, page 15).
 Built-in Programme (Profile A)ON 1OFF 1 ON 2OFF 2 ON 3OFF 3
Monday to 
Friday Heating
6:30am8:30am12:00pm 1:00pm4:30pm10:30pm
Hot Water 6:30am8:30am12:00pm 1:00pm4:30pm10:30pm
Saturday & 
Sunday Heating
6:30am9:30am12:00pm 1:00pm4:30pm11:00pm
Hot Water 6:30am9:30am12:00pm 1:00pm4:30pm11:00pm
 Built-in Programme (Profile b)
ON 1OFF 1 ON 2OFF 2 ON 3OFF 3
Monday to 
Friday Heating
6:30am9:30am12:00pm 1:00pm4:30pm11:00pm
Hot Water 6:30am9:30am12:00pm 1:00pm4:30pm11:00pm
Saturday & 
Sunday Heating
6:30am9:30am12:00pm 1:00pm4:30pm11:00pm
Hot Water 6:30am9:30am12:00pm 1:00pm4:30pm11:00pm
 Built-in Programme (Profile C)
ON 1OFF 1 ON 2OFF 2 ON 3OFF 3
Monday to 
Friday Heating
6:30am7:30am12:00pm 12:00pm 5:00pm10:00pm
Hot Water 6:30am7:30am12:00pm 12:00pm 5:00pm10:00pm
Saturday & 
Sunday Heating
8:30am9:30am12:00pm 1:00pm5:30pm10:30pm
Hot Water 8:30am9:30am12:00pm 1:00pm5:30pm10:30pm
ON 1OFF 1 ON 2OFF 2 ON 3OFF 3
Monday Heating
Hot Water
Tuesday Heating
Hot Water
Wednesday Heating
Hot Water
Thursday Heating
Hot Water
Friday Heating
Hot Water
Saturday Heating
Hot Water
Sunday Heating
Hot Water
Your Personal Programme
The table below has been left blank for you to record your own personal programme. 
						

							9
PROGRAMMING YOUR  ST9420C
Reviewing the Programme Times
To review your hot water programme, move the slider to the HOT WATER position. 
To review your heating programme, move the slider to the HEATING position.
To review the programme times, press the 
 button repeatedly. The appropriate 
ON and OFF markers will be displayed to show you which time is being reviewed. 
Any of these times can be adjusted by using the 
  or  buttons, and then 
confirmed using the  button. Remember to return the slider to the RUN  position 
after reviewing is complete.
Modifying the Hot Water Programme
The hot water programme has three pairs of ON/OFF switching times per day. Each 
time can be set between 3.00 am and 2.50 am (on the next day) to allow\
 you to 
programme the hot water to stay on past midnight, if required. 
a.  Move the slider to the HOT WATER position. ‘SET HOT WATER’ will show briefly 
to verify this action.
b.  ‘SET ON-TIME 1’ will then be displayed and the time setting for th\
e first ON 1 
time for MONDAY will now be flashing to indicate it can be changed. If you do 
not wish to change the time, press the green 
 button and move to the next 
step. If you do wish to make a change, use the   or  buttons to change 
the first ON 1 time. Each press of the button will change the time by 10 minutes. 
As soon as the time has been changed, the message ‘ON-TIME 1 OK?’ \
will be 
displayed. Press the green 
 button to confirm the time is correct and move to 
the next step. ‘SAVED’ will be displayed for a moment to confirm that any change 
has been saved to memory.
HOT WATER HEATING
DAY/TIME
HOT WATER HEATING RUN
HOT WATER HEATINGHOT WATERHEATING 
						

							10
Note: When pressing the  button the next ON or OFF marker may start to flash. 
This indicates you have tried to set a time equal to one of the next programme times 
already in the memory.  Similarly, when pressing the 
 button the previous ON or 
OFF marker may start to flash. This indicates you have tried to set a time equal to 
one of the previous programme times. If this happens the ST9420C simply moves 
both times together as long as you continue to press the 
  or  buttons.  Follow 
the procedure in ‘Reviewing the Programme Times’ (page 9) to check and adjust 
these times as necessary.
c. 
‘SET OFF-TIME 1’ will be displayed and the first OFF 1 time will now be flashing. If 
you do not wish to change the time, press the green  button and move to the next 
step. Otherwise, use the   or  buttons to change the time. Press the green  button to confirm the time is correct and move to the next step. ‘SAVED’ will be 
displayed for a moment to confirm that any change has been saved to memory.
d.  The remaining ON and OFF times (ON 2, OFF 2, ON 3, OFF 3) can be set by 
using the   or  buttons to change the time then the green  button to 
confirm the time is correct and move to the next step. If you do not wish to 
change the time, just press the green 
 button to move directly to the next ON/
OFF time without making any changes.
e.  After setting or reviewing the last off time, OFF 3, the message ‘COMPLETE’ will 
be displayed to indicate the times for Monday have been set.
You now have a choice of how to set the programme for the next day:
Copying One Day’s Programme to Another Day (example Monday to Tuesday):
f.   Whilst the day is showing Monday, Press the COPY DAY button. The message 
‘COPY MON TO TUESDAY OK?’ will be displayed and the letters TUE will flash 
to indicate the programme for Monday can be copied to Tuesday.
g.  To select a different day to copy to, press the NEXT DAY button to cycle through 
the days. With each press of the NEXT DAY button the message will change to 
indicate the new day you are copying to.
h.  When the required day is indicated, press the green 
 button to confirm, and 
the message ‘MON COPIED’ will be displayed for a moment. The day i\
nto which 
Mondays programme has been copied is now available to have its programme 
edited.
Note:  Once a day’s programme has been confirmed in this way, it now becomes the 
day whose programme is copied if the COPY DAY button is pressed again.
OR
Programming a Different Day:
i.  Press the NEXT DAY button to select the next day, which is displayed along the 
top of the screen.  The programme for that day can then be adjusted by following 
steps  b – e above.  Programmes for the remaining days can be set in the same 
way, using the NEXT DAY button to move to the next day.
PROGRAMMING YOUR  ST9420C