Honeywell CM900 Thermostat User Manual

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CM900 Wireless  
Installation Guide  
CM927 / CM921 Wireless Programmable  
Room Thermostat & BDR91 Relay Box  
Description  
Table of Contents  
Section  
The Honeywell CM900 Wireless (CM927 or  
a modern wireless programmable  
Page  
CM921) is  
1
2
) Installation Information ................................. 2  
room thermostat based on Honeywell’s proven  
programming philosophy. To further improve the  
ease of use, this product includes an extra large  
LCD display with backlighting and LoT Technology  
to assist customers during daily use.  
) Installing the CM900 Wireless System......... 3  
2.1 Installing the Relay Box................................... 3  
2
.2 Installing the Room Thermostat ........................ 4  
2.2.1 Power Up............................................... 4  
The CM927/921 room thermostat communicates  
with the BDR91 Relay Box on an 868MHz Radio  
Frequency (RF) band to control a single heating  
system component such as a boiler, pump or  
zone valve. Neither product will communicate with  
other RF products that use different frequencies or  
communication protocols.  
2
2
.2.2 RF Communication Check........................ 4  
.2.3 Locating the Room Thermostat ................. 5  
2.3 System Check................................................ 5  
3) Basic Operation of the System..................... 6  
.1 Automatic Operation....................................... 6  
3.2 Temporary Manual Override............................. 6  
.3 Communication Loss ...................................... 6  
3
Note: The RF link between the individual room  
thermostat (CM927/921) and Relay Box (BDR91)  
in system packs provided by Honeywell is pre-  
configured at the factory and therefore SHOULD  
be installed at the same site. This makes the  
installation process fast and easy, but if products  
from individual system packs are separated, or  
mixed with other pre-configured system packs  
during installations please refer to section 5.1  
Binding/RebindingProceduretobindthedesired  
units together and allow them to communicate with  
each other.  
3
4
) Installer Mode................................................. 6  
.1 Entering Installer Mode ................................... 7  
4.2 BDR91 Relay Box Fail-Safe Mode Setup............ 7  
4
4
.3 Using the Room Thermostat for Specific Applications .. 8  
.4 Using the Special Features of the Room Thermostat.. 8  
4
4.5 Installer Parameters Table ............................... 9  
4
4
.5.1 Category 1 - Room Thermostat Settings ..... 9  
.5.2 Category 2 - System Settings.................. 10  
5
6
) Additional Installation Information............. 11  
5
.1 Binding / Rebinding Procedure ...................... 11  
5
5
.2 Multi-Zone System........................................ 11  
.3 Binding an HR80 Radiator Controller  
to the Room Thermostat................................ 11  
) Trouble Shooting.......................................... 12  
6
6
.1 Trouble Shooting Guide................................. 12  
.2 Diagnostics Mode ........................................ 12  
5
0039987-003 A  
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1
) Installation Information  
As these products communicate using RF technology special care must be taken during installation. The  
location of the RF components as well as the building structure may influence performance of the RF  
system. To assure system reliability, please review and apply the information given below.  
Within a typical residential building the two products should communicate reliably within a 30m range. It  
is important to take into consideration that walls and ceilings will reduce the RF signal. The strength of  
the RF signal reaching the Relay Box depends on the number of walls and ceilings separating it from the  
room thermostat, as well as the building construction - the diagram below illustrates an example of typical  
signal strength reduction. Walls and ceilings reinforced with steel or plasterboard walls lined with metal foil  
reduce the RF signal significantly more.  
Once a position is selected for the room thermostat this can be checked using the RF Communication Test  
mode as described in section 2.2.3 Locating the RoomThermostat. If the position is unsuitable the Relay  
Box will not respond and an alternative position must be selected.  
=
Signal Strength  
Wall  
Wall  
Wall  
Ceiling  
Max. Signal Length 30 metres  
Typical example of Building Fabric Signal losses  
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2
) Installing the CM900 Wireless System  
Please follow the illustrations and information below in sequence to install the Relay Box and room  
thermostat correctly. For applications other than gas boilers, enabling special features and to see what  
other system options are available refer to section 4) Installer Mode.  
2
.1 Installing the Relay Box  
=
=
M3.5  
1
2
3 a.  
o
N 6  
2
The Relay Box is a RF device. For the  
best performance install in an open  
space. Leave at least 30cm distance  
from any metal objects including wall  
boxes and boiler housing.  
1
b.  
<
7mm Ø  
Do not mount on metal wall boxes. NOTE: The Relay Box contains  
no user serviceable parts. It  
should be opened and installed  
EMC compliance considerations  
>
7mm Ø  
Keep AC mains supply/load cables by qualified installer only.  
separate from signal wiring.  
WARNING: Electrostatic sensi-  
Refer to Code of Practice standards tive device! Do not touch the  
EN61000-5-1 and -2 for guidance.  
circuit board.  
4
Burner (direct control)  
Combi boiler  
5
A-B:5(3)A  
A-B:5(3)A  
A-C:5(3)A  
BDR91  
BDR91  
A-C:5(3)A  
2
30V  
230V  
50-60Hz  
<5A  
5
0-60Hz  
<
5A  
1
.5-2.5mm²  
Zone valve  
Cooling device  
6mm max.  
A-B:5(3)A  
A-C:5(3)A  
A-B:5(3)A  
A-C:5(3)A  
BDR91  
BDR91  
6
2
30V  
230V  
50-60Hz  
<5A  
5
0-60Hz  
1
<
5A  
V4043H  
NOTE: All wiring must be in accordance with IEE regulations  
CAUTION: Observe ambient temperature and current limits  
see the Relay Box wiring label)  
2
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Installation Guide  
3
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2
.2 Installing the Room Thermostat  
.2.1 Power Up  
2
1
. Remove the battery cover and insert the batteries supplied with the room thermostat (2 x AA LR6  
Alkaline Batteries).  
2
.
On the initial power up the available user interface languages will be displayed (only on certain models).  
Use the or buttons to cycle through the options until the desired language is displayed. Press the  
green button to confirm the selection.  
3
. Set the slider switch to the DATE mode.  
4
. Use the  
confirm.  
or  
or buttons to set the correct time, pressing the green  
Install the batteries (included) and attach the instruction label to flap  
buttons to set the correct day / month / year, pressing the green  
button to  
5
. Use the  
button to confirm.  
2
.2.2 RF Communication Check (Test Mode)  
To check the RF communication, hold the room thermostat about 2-3 metres from the installed Relay Box.  
Move the slider on the room thermostat to the OFF position then press the and buttons together  
with the button for 3 seconds. The unit will display ‘TEST TRANSMIT’ and it will send test signals to the  
Relay Box, flashing the green LED on every 6 seconds (relay output will remain off) for a maximum of 10  
minutes. When the green LED flashes on every 6 seconds proceed to the next step.  
NOTE: If the green LED is not switched at specified intervals, the red LED is flashing or if you are installing  
a replacement Relay Box or room thermostat, follow the procedures described in section 5.1 Binding /  
Rebinding Procedure.  
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.2.3 Locating the Room Thermostat  
While still in the Test Mode, as described in section 2.2.2, the room thermostat should be located taking  
the following into consideration and reviewing the illustrations below:  
1
2
3
.
Find a suitable location where the signal transmission is reliable. Reliable transmission is indicated when  
the Relay Box is flashing the green LED every 6 seconds. NOTE: The Relay Box relay will be off.  
. Install the room thermostat EITHER on the wall using the wall bracket OR attach the optional table stand  
as shown in below.  
. Exit the Test Mode by moving the setting slider to the required operating mode (AUTO or OFF).  
Wall bracket  
Table stand  
✗
✗
✓
1
.2m  
•
•
The room thermostat should be installed in an open space for best performance as it is a radio frequency device.  
Leave at least 30cm distance from any metal objects including wall boxes and at least 1 metre from any other  
electrical equipment eg. radio, TV, PC etc.  
•
Do not mount onto metal wall boxes. • It is recommended that the Relay Box is fully installed.  
2
.3 System Check  
Now a simple test can be completed to check the full system has been installed correctly:  
1
2
3
4
. Set the slider switch to the OFF mode.  
. Check the boiler supply is on and check that the green LED on the Relay Box is off.  
. Set the slider switch to the MAN mode.  
. Adjust the setpoint up to the maximum (35°C) by pressing the  
button. The boiler should come on  
(
green LED ON on Relay Box) after a few seconds and the symbol appears on the room thermostat  
LCD display.  
5
6
. Set the slider switch to the OFF mode. The boiler will go off (green LED OFF on Relay Box) after a few  
seconds and the symbol disappears.  
. Check the system operation by moving the slider between MAN and OFF modes several times, bearing  
in mind the switching delay referred to above.  
Now, you should have completed the installation successfully - to begin operating at the default factory  
settings move the slider to the AUTO mode or select PROG to modify the built-in heating program  
accordingly.  
Installation Guide  
5
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3
) Basic Operation of the System  
3
.1 Automatic Operation  
BDR91 Relay Box  
The Relay Box receives the heat demand (0-  
00%) signal from the room thermostat. The  
room thermostat will display the symbol on the  
1
LCD display whenever more heat is required.  
Depending on the demand the Relay Box will  
switch the heating device on to match the current  
requirements of the system.  
Push button and  
relay status LED’s  
The green LED indicates the status of the relay  
output:  
•
•
Green LED on = relay on  
Green LED off = relay off  
3
.2 Temporary Manual Override  
Pressing the Relay Box button will override the current relay position. As soon as the next signal is received  
from the room thermostat the Relay Box will return back to automatic operation as the automatic control  
has higher priority than manual operation.  
3
.3 Communications Loss  
If the RF communication is lost for a period of 1 hour the red LED will illuminate to indicate that no RF  
messages have been received during the last hour.  
The Relay Box will also enter the failsafe mode as selected in Installer Mode (see section 4.2 BDR91  
Relay Box Fail-Safe Mode Setup). To allow manual control of the Relay Box output manual override is  
available in fail-safe mode. When RF communication is restored the Relay Box will automatically return to  
normal operation.  
You can now use the USER GUIDE supplied with the room thermostat to demonstrate how it works to the  
home owner.  
4
) Installer Mode  
Installer Mode is used to alter the system settings for specific applications, to use the special features of  
the room thermostat in a different way or to alter the factory preset parameters. Parameters are divided  
into two groups:  
-
-
Category 1 parameters – Room Thermostat Setup  
Category 2 parameters – System Setup.  
These are all listed in section 4.5 Installer Parameters Table.  
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.1 Entering Installer Mode  
1
2
D A Y  
COPY  
D A Y  
D A T E  
PROG  
AU TO  
MAN  
OFF  
OFF  
C M 9 2 7  
1..6  
The unit will display the first parameter of installer  
parameter group category 1 (from Parameter n.1  
to n.19) as shown  
Move the slider switch to the OFF mode.  
Press and hold the button and the two  
buttons together.  
&
3
4
Press the  
change factory setting.  
or  
to  
Press the green  
button to confirm the  
change.  
The display will flash  
indicating that a change  
has been made.  
The display will stop  
flashing.  
5
6
7
Press  
button to go to Installer parameter group  
Press  
to the next parameter.  
button to go  
category 2 ( ) (from Parameter n.1 to n.14).  
To exit the installer mode, move the slider switch to  
the AUTO or MAN positions.  
4
.2 BDR91 Relay Box Fail-Safe Mode Setup  
The failsafe mode defines the Relay Box output relay status if the RF communication is lost (e.g. when  
the room thermostat stops communicating due to discharged batteries). The factory setting keeps the  
relay permanently off when communications is lost. If this factory setting needs to be changed follow the  
instructions below:  
1
2
3
4
. Enter Installer mode as described above.  
. Press the  
button to enter category 2 parameters.  
. Select the parameter 7:LC by pressing the  
. Select the fail-safe mode by pressing  
button.  
or buttons:  
•
0 - when RF communication is lost the relay will be held in OFF position.  
1 - when RF communication is lost the relay output will cycle at 20% on 80% off.  
button to accept the change.  
. Attach appropriate label to the Relay Box to indicate the selected fail-safe mode.  
•
5
. Press the green  
6
IMPORTANT: To enable the frost protection when RF communication is lost, select the fail-safe mode 1. For  
systems with separate frost protection thermostat or where frost protection is not required select fail-safe  
mode 0.  
Installation Guide  
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4
.3 Using the Room Thermostat for Specific Applications  
The CM927/921 RF room thermostat is a versatile controller that can be used to control many different  
applications. For most typical applications, like wall-hung gas fired combination boiler control or zone  
valve control, no adjustments from the factory settings are required. For other applications, like controlling  
an oil burner, the best system performance can be achieved by modifying selected parameters of the  
room thermostat in the Installer mode. The table below lists the most common settings used for specific  
applications.  
Specific Application:  
Setting:  
What to change:  
Cycle/  
Hour  
Minimum ON Note: All parameters listed below belong to category 2  
Time  
- System Parameters (see Installer Parameters Table)  
HEATING  
Gas Boiler (<30kW)  
6
3
1
4
No changes required  
Oil Boiler  
Set 1:Ot parameter to 4  
Set 2:Cr parameter to 3  
Thermal Actuator  
Zone Valve  
12  
6
1
1
Set 2:Cr parameter to 12  
No changes required  
AIR-  
CONDITIONING  
To enable switching between cooling and heating  
modes adjust parameter 4:HC in category 2 (0 =  
disabled, 1 = enabled). Now you can switch between  
these modes by pressing the  
and  
buttons  
together for 5 seconds in any of the product operating  
modes (AUTO, MAN or OFF). Explain to the end user  
how to switch between these modes using the  
buttons and ensure the cooling program is modified  
as required.  
and  
Heat Pump / Air-  
Conditioner  
3
6
4
1
Set 1:Ot parameter to 4  
Set 2:Cr parameter to 3  
Fan Coil  
No changes required  
4
.4 Using the Special Features of the Room Thermostat  
Special Feature:  
Description:  
Enable/Disable  
Optimisation  
The thermostat will adjust the start time in the morning/afternoon so the  
desired temperature is reached by the start of the program period. The  
system will restrict the start time to a max of 2 hours.  
To enable: Set parameter 8:  
OP (category 1) to 1.  
(
Variable Start  
Time)  
Heating or Cooling  
Operation  
This product can be used for heating or cooling applications. If you select  
cooling mode the control algorithm and factory default program will be  
modified. You can independently modify the heating and cooling profile.  
To enable: Set parameter 4:  
HC (category 2) to 1.  
Summer/Winter  
Auto time change  
This feature moves time automatically on the last Sunday of March and  
the last Sunday of October. The feature is factory enabled.  
To enable: Set parameter 3:  
tC (category 1) to 1.  
Temperature Offset  
If the thermostat is located in a particularly hot/cold location for reliable  
signal transmission reasons then the measured/displayed temperature  
can be adjusted by +/- 3°C. This is useful if the homeowner wants the  
reading to match another appliance temperature display.  
Set parameter 12:tO  
(category 1) to the required  
offset value.  
Upper/Lower  
Temperature Limit  
The normal upper temperature limit of 35°C can be reduced to 21°C  
to save the homeowner energy. The normal lower limit of 5°C can be  
increased up to 21°C to protect inhabitants from cold.  
Set parameter 6:uL (category  
1) to the desired upper limit.  
Set parameter 7:LL (category  
1
) to the desired lower limit.  
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4
.5 Installer Parameters Table  
.5.1 Category 1 - Room Thermostat Settings  
Parameter  
Parameter Factory Default Setting  
No.  
Optional Setting  
Category 1 Parameters – Room Thermostat Settings  
Display Description  
24 24 hr clock display  
Display Description  
AM-PM / 24hr  
Display  
1:CL  
2:rP  
12  
12 hr – AM/PM clock display format  
format  
Reset Time/ Temp  
Program  
1
Time / Temp profile set  
to factory default  
0
Time / Temperature are as programmed  
To restore the factory profile set to 1  
Changes to 0 when  
one of the time/temp  
profiles are changed  
Auto Summer/  
Winter Time  
Change  
3:tC  
1
Auto Summer/Winter  
Time Change Enabled  
0
0
Auto Summer/Winter Time Change  
Disabled  
LCD Backlighting  
Upper Temp Limit  
5:bL  
6:uL  
1
Backlighting Enable  
Backlighting Disabled  
35  
35°C Upper Temp.  
Limit  
21 to  
34  
21°C to 34°C adjustment in 1°C steps  
Lower Temp Limit  
Optimisation  
7:LL  
8:OP  
12:tO  
5
0
0
5°C Lower Temp. Limit 5 to 21 6°C to 21°C adjustment in 1°C steps  
Optimisation Disabled  
No temperature offset  
1
Optimisation Enabled  
Temperature Offset  
-3 to  
-3°C to +3°C adjustment in 0.1°C steps  
+
3
Proportional Band  
Width  
13:Pb  
19:FS  
1.5  
1
Proportional band of  
1.5 degrees  
1.6 to  
3.0  
1.6°C to 3.0°C adjustment in 0.1°C steps  
Settings are as modified above  
Reset Parameters  
to Factory Defaults  
All settings at factory  
defaults  
0
Changes to 0 when  
one of the parameter  
is changed  
To restore the factory profile set to 1  
Notes  
1
) Remember to always press the green button to confirm that you want to store your new Installer Set-  
Up setting. To exit the Installer Mode move the slider switch to the AUTO or MAN position.  
Installation Guide  
9
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4
.5.2 Category 2 - System Settings  
Parameter  
Parameter Factory Default Setting  
No.  
Optional Setting  
Category 2 Parameters – System Settings (press the  
Display Description  
1 minute minimum  
button to access this category)  
Display Description  
Minimum boiler  
ON time  
1:Ot  
2:Cr  
1
2 to 5  
Selection of 2, 3, 4 or 5 minutes  
ON time  
minimum ON time  
Cycle Rate  
6
6 cycles per hour  
3,9 or  
12  
Selection of 3, 9 or 12 cph  
(
cph)  
Heat/Cool Change  
Pump Exercise  
4:HC  
5:PE  
0
0
Disabled  
1
1
Enabled  
Pump exercise  
disabled  
Pump exercise enabled  
System  
Synchronisation  
6:Sn  
7:LC  
0
0
Standard operation of  
the Room Unit  
1
1
Room unit configured as Synchroniser  
Relay 20% on / 80% off  
Loss of  
Relay Off  
Communications  
Instruction  
The following Parameters are for the control of other Honeywell Wireless products such as Wireless Underfloor Heating  
controls and Wireless Radiator controls. For more information please contact Honeywell sales.  
Room Temperature  
Sensor Use  
8:Su  
0
BDR91 control  
1,2,3  
or 4  
1 - HR80/HM80 control with own/remote  
sensor (no temperature displayed)  
2
- HR80/HM80/HCE80 control with CM  
sensor  
3
- BDR91 control and HR80/HM80/  
HCE80 control with own/remote sensor  
4
– Hr80/HM80/HCE80 control with own/  
remote sensor (temperature displayed)  
HR80 Window-  
Open Function  
9:HO  
10:HL  
11:uF  
12:LF  
13:Ar  
14:Pr  
0
1
Disabled  
Enabled  
1
0
Enabled  
HR80 Local  
Override  
Disabled  
Maximum Flow  
Setpoint  
55  
15  
150  
15  
55°C Maximum Flow  
Temp.  
0 to 99 0°C to 99°C adjustment in 1°C steps  
0 to 50 0°C to 50°C adjustment in 1°C steps  
Minimum Flow  
Setpoint  
15°C Minimum Flow  
Temp.  
Mixing Value Run  
Time  
150 seconds  
0 to  
240  
0 to 240 sec. adjustment in 1sec steps  
Pump Overrun Run  
Time  
15 minutes  
0 to 99 0 to 99 mins adjustment in 1min steps  
Notes  
1
2
3
) Remember to always press the green  
Up setting. To exit the Installer Mode move the slider switch to the AUTO or MAN position.  
button to confirm that you want to store your new Installer Set-  
) These parameters are set centrally for the zoning system at the room thermostat configured as the  
system synchroniser.  
) Minimum on-time setting applies only to the boiler controller. All Relay Box zone controllers will work  
with the minimum on-time of 30 seconds.  
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5
) Additional Installation Information  
5
.1 Binding / Rebinding Procedure  
The binding operation described below is required if:  
•
•
Any of the system components (room thermostat or Relay Box) are replaced.  
The Relay Box has incorrect or no binding data stored (e.g. when pre-bound system pack components  
have been mismatched).  
NOTE: During the binding procedure keep approximately 1m distance between the room thermostat and  
the Relay Box.  
To bind/rebind:  
1
. Press and hold the Relay Box push button for 15 seconds to reset any previously stored data. After 15  
seconds the red LED will change to flashing 0.1sec on/0.9sec off.  
NOTE: After 5 seconds the red LED will start to flash 0.5sec on/0.5sec off, but continue to hold the button).  
. Release the push button.  
2
3
. Press and hold the Relay Box push button for 5 seconds to enter the binding mode. The Red LED will  
start flashing at 0.5sec on/0.5sec off to confirm the binding mode has been entered.  
4
5
6
. Move the room thermostat slider to the OFF position and press the  
and buttons together along  
with the  
button. The unit will display InSt and ‘CONTROL BINDING’.  
.
Press the green  
button to send the binding signal out to the Relay Box. The red LED is switched off to confirm  
successful binding operation. If the red LED still flashes push the button again until binding is successful.  
. Now go to Section 2) Installing the CM900 Wireless System to setup the system.  
5
.2 Multi-Zone System  
Multiple room thermostats and Relay Box sets can also be used to control multi-zone systems and the  
CM927/921 room thermostat is compatible with a variety of other Honeywell products including HR80 radiator  
controllers (see below) and HCE80 underfloor heating controllers. If you intend to use it in this way additional  
installation and user instructions can be obtained by contacting the address at the end of this guide.  
NOTE: Some of the labels supplied with the pack are for use in multi-zone applications.  
5
.3 Binding an HR80 Radiator Controller to the Room Thermostat  
1
. Press the bind button (1) for approximately one second and release. When the  
button is released, the symbol flashes and the software version number is  
displayed for 30 seconds.  
1
2
.
Move the room thermostat slider to the OFF position and press the and buttons  
together along with the button. The unit will display InSt and ‘CONTROL BINDING’.  
. Press the green button to send the binding signal out to the radiator controller.  
. The radiator controller will display once the signal has been received.  
3
4
If several radiator controllers are to be controlled simultaneously in one room:  
1
. Press the bind button on all the radiator controllers to be bound to the room  
thermostat. The symbol flashes continuously on the display of the radiator controller.  
. Move the room thermostat slider to the OFF position and press the and buttons together along  
with the button. The unit will display InSt and ‘CONTROL BINDING’.  
2
3
. Press the green  
button to send the binding signal out to the radiator controllers.  
4
. The radiator controllers will display  
once the signal has been received. The set temperature at the  
radiator controller is automatically set to 20°C.  
NOTE: The radiator controller can take up to 4 minutes to receive data from the room thermostat.  
Installation Guide  
11  
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6
) Trouble Shooting  
6
.1 Trouble Shooting Guide  
Symptom (Fault  
Possible Cause  
Remedy  
Message)  
The room thermostat  
This is normal operation. The Relay Box cycles  
the relay on and off for times proportional to  
the demand signal (0-100%) from the room  
thermostat. The symbol only indicates that the after a few seconds delay.  
demand value is greater than 0%.  
Using the  
button change the  
displays the symbol but  
the Relay Box relay does  
not switch on.  
temperature setpoint by a few degrees.  
The Relay Box should switch the relay on  
The Relay Box does not  
react to setpoint changes  
on the room thermostat.  
The room thermostat and Relay Box are not  
bound.  
Reset the Relay Box by pressing and  
holding the push button for 15 seconds.  
Then follow the binding / rebinding  
procedure as described in section 5)  
Additional Installation Information.  
After the binding procedure  
the red LED is on and the  
green one is flashing once  
every 3 sec on the Relay  
Box.  
Incorrect or incomplete binding procedure.  
Repeat the binding procedure.  
Incorrect position of the room thermostat during  
binding.  
Repeat the binding procedure keeping  
approx. 1 m distance between the Relay  
Box and the room thermostat.  
The red LED on the  
Relay Box is illuminated  
The Relay Box receives no RF messages from  
the room thermostat:  
(
Communication loss)  
RF signal is blocked due to wrong location of the Re-locate the room thermostat following  
room thermostat.  
instructions in section 2) Installing the  
CM900 Wireless System.  
Room thermostat batteries are exhausted.  
Replace batteries in the room thermostat.  
6
.2 Diagnostic Mode  
The CM927/921 room thermostat has a user accessible mode that provides information useful to a remote  
service person and a means of checking whether the boiler is working. To access this move the slider  
switch to the OFF position then press and hold the button for 5 seconds. The room thermostat will enter  
the user settings mode. Next press and hold the and  
buttons together. The room thermostat will hold  
the relay on for 5 minutes and the following information can be viewed on the display by pressing the  
or buttons. : model ID, date code (WW/YY) & checksum.  
Hereby, Honeywell declares that this CM927/CM921 room thermostat and BDR91 Relay Box are in  
compliance with the essential requirements and other relevant provisions of Directive 1999/5/EC, 2006/95/EC  
and 2004/108/EC.  
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, Switzerland by its Authorised Representative Honeywell International Inc.  
Honeywell Control Systems Ltd.  
Arlington Business Park,  
Bracknell, Berkshire  
RG12 1EB  
Technical Help Desk: 08457 678999  
5
©
0039987-003 A  
2009 Honeywell International Inc.  
www.honeywelluk.com  

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