Honeywell Sundial RF Pack 1 Wireless Enabled Timer and Thermostat User Manual

							21
DT92E OPERATING INDICATORS
Low Battery Indicator / Battery Replacement
The battery symbol will start 
to flash if the battery power is 
running low. From this point, 
there will be a minimum of 4 
weeks before the product will 
cease to function.
Batteries are accessed by 
unclipping the front cover at the 
bottom. Note battery polarity. 
Reverse process to refit front 
cover.
Use 2xLR6 (AA) alkaline 
batteries only. 
Immediately on power up, DT92E will try to communicate and synchronise with 
ST9120C. This process may take up to 4 minutes, and will be indicated by the word 
‘Sync’ on the DT92E display.
RF Communications Indicator
A brief flash of the RF symbol  indicates the DT92E 
has been communicating with the other system 
controls.
Lockout
Your DT92E works in conjunction with the ST9120C 
time control. If the timer is set to OFF or CONT it may 
not be possible to override it from the thermostat 
and this is indicated by the lockout symbol 
. To 
switch the heating on you must go to the timer and 
set the Mode to AUTO, ONCE, or CONT. 
2 x LR6 AA Alkaline
1
2 
						

							22
DT92E ENERGY SAVING ECO FEATURE
The ECO button allows you to change to a lower, energy saving set temperature for 
a period of your choice, from 1 to 24 hours. This temperature is pre-set in the DT92E 
Installer Mode, but you can adjust this to any temperature you want when ECO mode 
has been activated. The default ECO temperature is 18°C.
At the end of the time period, the thermostat will return to its original set 
temperature.
Entering ECO Mode and Setting 
the Energy Saving Time Period
Press the green ECO button to enter ECO 
mode. The word ECO will appear on the 
display and the thermostat will allow you to 
set the number of hours you want to be at 
the new set temperature.
Use the 
 and  buttons to set the hours, 
up to a maximum of 24 hours.
Please note – ECO mode is not accessible 
in Holiday mode or if Service shutdown 
has occurred.
What Happens in ECO Mode?
In ECO mode, the display will show a 
countdown of the remaining time (hours 
and minutes) in ECO mode, identified by 
the hourglass symbol. The display will 
alternate every 5 seconds to show the 
current room temperature.
When in ECO mode, pressing the 
 or  
buttons will adjust the set temperature for 
the remainder of the ECO time period. 
5 s 5 s
5 s
1,2,3,4....,24hr 
						

							23
DT92E ENERGY SAVING ECO FEATURE
FINE TUNING YOUR  DT92E
Changing the DT92E Installer Parameters
The DT92E 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.
INSTALLER 
PARAMETERParameter
Default 
Value Options
Description
Temperature 
measurement offset t0
0-3 to 3 K Offset to measured 
temperature
Upper setpoint limit uL3521 to 
35°C Upper set temperature 
limit in °C
Lower setpoint limit LL55 to 21°C Lower set temperature 
limit in °C
Energy saving ECO 
setpoint ES
185 to 35°C Energy saving ECO set 
temperature in °C
Reset parameters 
to factory settings FS
10, 1Parameter will be set to 0 
if any of the other param-
eter values have been 
changed. Set to 1 to get 
back to factory settings.
How to Exit ECO Mode
To exit ECO mode, simply press the green 
ECO button again. ECO will disappear 
from the display and the thermostat will 
control to its previous set temperature. 
						

							24
To Enter Installer Mode:
a. Hold the 
 button for 2 seconds until DT92E is in standby mode.
b. Hold 
 and  buttons for 3 seconds until the word ‘Inst’ appears on the 
display.
c.  Press the 
 button.
The first parameter is now ready to be changed.
To Select a Parameter:
Use the 
 and  buttons to move from one parameter 
to the next. Stop at the Parameter you wish to change.
To Change a Parameter:
Use the standby button to select the parameter value, then the 
 and  buttons to 
change the value. Confirm the change by pressing the  button again to take you 
back to the parameter.
To Exit Installer Mode:
Hold the 
 button for 3 
seconds to exit Installer 
Mode.
Note: The Installer Mode will 
exit automatically after 10 
minutes if  no adjustments 
have been made in this 
time.
FINE TUNING YOUR  DT92E
3 s
3 s
2 s 
						

							25
Automatic Operation
The BDR91T relay box simply switches the boiler on 
and off according to a wireless signal it receives from 
the ST9120C timer. It is mainly used when the boiler 
is installed  in a remote location where it may be 
difficult to run wires direct from the timer. The green 
light indicates the status of the relay output:
Green light on = relay on
Green light off = relay off
Temporary Manual Override
In normal operation it should not be necessary to 
interact with the BDR91T. However it is possible to 
press the button and temporarily override the current 
relay position. This will be cancelled as soon as the 
Relay Box receives another signal from the ST9120C 
timer, because automatic operation has a higher 
priority than manual operation.
Loss of Wireless Communications
If the RF communication is lost for a period of 1 hour the red light will illuminate.
The Relay Box will then enter the failsafe mode as selected by your Installer (see 
page 30).
When RF communication is restored, the Relay Box will automatically return to 
normal operation.
OPERATING YOUR BDR91T RELAY BOX (IF INSTALLED)
Green LED
Red LED
Push button 
						

							26
FAQ  AND TROUBLESHOOTING
How do I set the time only, if the ST9120C clock is not correct?
Your ST9120C contains an accurate digital clock that is factory set. Should you ever 
need to change the time, just follow this procedure:
a. Move the slider to the DAY/TIME position.
b.  Keep pressing the green 
 button until the message ‘SET THE TIME’ is 
displayed. To change the time, press the   or  buttons until the correct 
time is shown. 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’.
c.  Move the slider to the RUN  position, to complete changing the time.
What do I do when the clocks go back in October and forward 
in March?
Your ST9120C is factory set to change the clock automatically at the correct dates, 
so you should never need to adjust the clock forward or backwards yourself. It is 
possible to disable this particular feature, as described in the section ‘Changing the 
Installer Parameters’ (page 15). You may also check the section ‘Configuration & 
Service Data’ (page 30) to see how your Installer has configured your product.
What should I do if I get ‘lost’ while programming the ST9120C?
The LoT™ Display on ST9120C will provide you with help and tips to work through 
the programming. Should you ever get ‘lost’, the simplest thing to do is\
 to move the 
slider to the RUN  position, and then move it back to the appropriate programming 
position where you got lost. At this point just follow the instructions again.
What happens if there is a power failure?
In the event of a mains power failure, the ST9120C display will go blank, the 
indicator lamps will go out, and the control outputs will switch off. The real time 
will be constantly maintained by means of the built-in battery backup, ready to 
power back up as if nothing had happened when the mains power is restored. In 
addition, all programmes and settings are stored in a special memory (called Non 
Volatile  memory) which requires no power to maintain information so will be retained 
indefinitely.
Should the correct time and date ever be lost, for whatever reason, the message ‘SET 
DATE + TIME’ will be displayed whilst the slider is in the RUN  position. In this case, 
simply follow the procedure described under ‘Step 1: Setting the Date & Time’ 
(page 6). It should not be necessary to make any changes to your programmes. 
						

							27
FAQ  AND TROUBLESHOOTING
How reliable is 2-way RF communication?
The 2-way RF communication (also known as wireless communication) used by 
Honeywell is extremely robust and reliable. When installed correctly the Signal 
Strength test feature allows the Installer to locate the system components where 
mutual signal reception is strong. During communication, signals are sent several 
times to ensure receipt, and if any message is garbled, the error detection software 
recognises this and ensures the message is repeated again.
What do I do if RF communication is lost?
Follow the steps in the Troubleshooting Guide on the next page. The most likely 
cause for loss of communications is the DT92E batteries running low on p\
ower. This 
will be indicated on the DT92E display by a flashing battery symbol, or the display 
may even be blank. Simply replace the batteries (as shown on page 21) and wait a 
few minutes for communications to become re-established.
If this does not resolve the problem it may be that the RF signal path between 
the ST9120C and the DT92E is blocked by a metal object. Check the direct path 
between the two devices and reposition any object that may be blocking the signal, 
or move the thermostat.
How do I know when to change the batteries in the DT92E 
room thermostat?
If the DT92E batteries need changing, the battery symbol will flash on the DT92E 
display. DT92E will continue to operate for at least 4 weeks after the indicato\
r begins 
to flash. The ST9120C will also show the message ‘SENSOR LOW BATT’ and the 
radiator symbol 
 will flash. It is important to change the DT92E batteries as soon 
as the low battery condition is indicated, as reduced battery power may affect the 
RF signal strength and impair RF communications.
Can I override the Timer from the DT92E thermostat?
As well as changing the set temperature from the DT92E, it is also possible to 
override the heating system on or off from the DT92E.  This is only possible if the 
ST9120C is in AUTO or ONCE Modes. If ST9120C is in CONT mode it will not\
 be 
possible to switch the heating off from the DT92E. Similarly, if ST9120C is in OFF 
mode, it will not be possible to switch the heating on from the DT92E. If these latter 
overrides are required it is first necessary to change the ST9120C mode setting to 
AUTO or ONCE. 
						

							28
FAQ  AND TROUBLESHOOTING
Troubleshooting Guide
This is a quick guide to help you diagnose and cope with possible problems with 
your wireless control system. For further assistance, please contact your Installer.
SymptomPossible CauseRemedy
ST9120C has a blank 
LCD display No power to the 
heating systemCheck that there is power to the 
heating system
Fault in ST9120C
Call Installer
ST9120C indicates 
the system is ON, but 
radiators are cold and/
or taps are running with 
cold water.
Temperature controls 
are switched off or 
set too lowCheck that the temperature controls in 
the system are set to appropriate levels
Boiler or other 
system controls 
have malfunctioned Call Installer
ST9120C shows the 
message: 
‘INTERNAL FAULT’ Fault in ST9120C
Call Installer
Every few seconds, the 
ST9120C screen shows 
the message:  ST9120C is counting 
down the number of 
days until your next 
boiler service is due.Arrange a boiler service before the 
counter reaches zero.
After servicing your boiler, the Service 
Engineer / Installer will reset the 
ST9120C to remind you when the next 
boiler service is due. Each service is 
normally a maximum of 1 year apart.
Although the heating 
is still operating, the 
ST9120C screen keeps 
flashing the message:Your boiler service is 
overdue.
Arrange an immediate boiler service.
After servicing your boiler, the Service 
Engineer / Installer will reset the 
ST9120C to remind you when the next 
boiler service is due. Each service is 
normally a maximum of 1 year apart.
The ST9120C screen 
shows the message: Your boiler service 
is overdue and 
the boiler has 
been automatically 
switched off to 
ensure your safety.Arrange an immediate boiler service.
If set to do so, it may be possible to 
obtain limited use of the boiler by 
pressing the EXTRA HOUR button. 
Each button press will allow operation 
of the boiler for 1 hour at a time, and 
the screen will display the message 
‘On 1h’.
After servicing your boiler, the Service 
Engineer / Installer will reset the 
ST9120C to remind you when the next 
boiler service is due. Each service is 
normally a maximum of 1 year apart. 
						

							29
SymptomPossible CauseRemedy
ST9120C shows the 
message ‘SENSOR LOW 
BATT’ and a flashing 
radiator symbol DT92E batteries 
are running low on 
power Change the DT92E batteries (see page 
21 for how to do this)
DT92E shows a flashing 
battery symbol 
DT92E display is blank
ST9120C shows the 
message ‘NO SIGNAL’ 
and a flashing radiator 
symbol 
 and DT92E 
shows a flashing RF 
symbol 
DT92E batteries are 
running low on powerChange the DT92E batteries (see page 
21 for how to do this)
RF communication 
path between 
ST9120C and 
DT92E is blocked, 
possibly by a 
metal object Check direct path between both 
products and re-position any objects 
that may be blocking the signal
Relocate the DT92E, if possible
ST9120C shows the 
message ‘NO SIGNAL’ 
and a flashing flame 
symbol 
Red light on BDR91T 
(if installed) is lit 
continuously RF communication 
path between 
ST9120C and 
BDR91T is 
blocked, possibly 
by a metal object
Check direct path between both 
products and re-position any objects 
that may be blocking the signal
ST9120C shows the 
message ‘SENSOR 
FAULT’ and a flashing 
radiator symbol 
DT92E display shows 
‘’ and a flashing 
spanner symbol   Fault with DT92E
Call Installer
Troubleshooting Guide (cont.)
FAQ  AND TROUBLESHOOTING 
						

							3050047645-005 A
CONFIGURATION & SERVICE DATA
Configuration Data (to be completed by Installer)
The tables below are for the Installer to complete to indicate how your ST9120C and 
DT92E have been configured.
Application
Insert application number as per Installation wiring diagrams:
Configurable FeaturesOptionsFactory 
settingInstaller configured 
(tick box or note value)
ST9120C Configuration - standard
24hr or am/pm clock 
display. am/pm display
24hr display
Display backlight operation. Off
on if button pressed
on continuously
Automatic time change.disabled,
enabled
1-day or 5/2-day or 7-day 
operation.1-day operation
5/2-day operation
7-day operation
Number of ON/OFFs per 
day.2 on/offs per day,
3 on/offs per day
Default time programme.
A = standardb = at home
C = economy
Hot water set temperature From 40 to 85°C60°C
Optimum start no optimum start
delayed start
optimum start on
Optimum start limit 1 hour
2 hours
3 hours
Optimum stop disabled
enabled
Frost protection temperature From 5 to 16°C5°C
Minimum ON/OFF time 1, 2, 3, 4, 5 minutes1 minute
Cycle rate 3, 6, 9, 12 cycles 
per hour6 cycles
Proportional band width From 1.5 to 3.0°C1.5°C
Failsafe mode (loss of RF 
communications) Off
On 20%