Honeywell CM721, CM727 - Programmable Thermostat Manual

Description of the CM721

The Honeywell CM721 is a programmable room thermostat designed to control your heating system efficiently, providing comfortable temperatures when you are at home and energy savings when you are away. The following instructions explain how to program and use the thermostat to provide the most home comfort at the least cost.

Features of the CM721

• Ergonomic user interface featuring an 'OK-button'.
• Large LCD (Liquid Crystal Display) Screen.
• 4 independent temperature levels (from 5°C to 35°C).
• Automatic Summer/Winter Time Change.
• Optimum Start to achieve the right temperature at the right time.
• Built-in Memory holds the user program indefinitely.

Controls Layout of the CM721

1. LCD Screen

2. Battery Low Indicator

3. Time Display

4. Burner On Indicator

5. Temperature Display

6. Temperature Change Buttons

7. Temperature Enquiry Button

8. Operating Mode Buttons

9. Green OK Button

10. Battery Compartment

11. Battery Cover

12. Program Buttons

13. Time Change Buttons

14. Set Date Button

SETTING-UP THE CM721

This section shows you how to setup and run the thermostat in 3 simple steps:

STEP 1: Installing the Batteries

Note:
Please follow the instructions in this section only if the thermostat screen is blank (no symbols or digits are displayed). If the room temperature is already displayed move on to Step 2: Setting the Date and Time.

To install the Batteries:

1. Lift up the front cover of the thermostat to reveal the battery cover and product controls.
2. Remove the battery cover by pressing down and sliding out.
3. Insert the 2 x AA LR6 Alkaline Batteries supplied with the thermostat, ensuring the correct orientation
4. After a short pause the thermostat will display information on the screen and is now ready for use.
5. Replace the battery cover by sliding it firmly back into the front of the thermostat.

STEP 2: Setting the Date and Time

To set the Date and Time:

1. Press the DATE button to begin setting the date. When you set the date for the first time after the batteries are inserted, the display will show:
   Press the or buttons to set the current day of the month (e.g. d 01 = 1 st day of the month) then press the green button to confirm.
   

2. Press the or buttons to set the current month of the year (e.g. m 01 = January) then press the green button to confirm.
   

3. Press the or buttons to set the current year (e.g. yr 06 = 2006) then press the green button to confirm. The date is now stored.
   

4. Use the orbuttons to set the correct time then press the green button to confirm. Each press of the buttons will change the time by one minute and holding them down will AM change the time slowly at first and get progressively quicker.
   
   Note:
   If this mode is entered accidentally then press the AUTO, MAN or OFF buttons to exit.

STEP 3: Running the Built-in Heating Program

The thermostat is now ready for operation. Press the AUTO button and the built-in heating program will start running.
Note:
The built-in heating program has been designed to provide normal comfort requirements, but if you want to customise the settings please see the next section 'Programming the CM721'.

PROGRAMMING THE CM721

The Built-in Heating Program

The built-in heating program has 4 temperature level changes that can be set between 3.00am and 2.50am the following day - allowing you to maintain the evening temperature after midnight. Each temperature level can be set between 5°C and 35°C, and adjusted in 0.5°C increments. The factory default program for heating is as follows.

Reviewing the Heating Program

To review or edit the heating program use the PROGRAM or buttons to navigate between the 4 individual programming periods.

Modifying the Heating Program

To change the heating program:

1. Press either of the PROGRAM or buttons to enter the programming mode. The time / temperature settings for period will be flashing as shown. The active period is highlighted by a flashing square around the numbers at the bottom of the screen.
   
2. To adjust the period start time use the or buttons, the display will stop flashing and the 'OK?' indicator will be displayed. Holding the button down will change the time quickly.
   Note:
   If you are pressing the or buttons and the display flashes the next period, it means the next period will be pushed forward.

3. Once the required time is reached press the green button to confirm.
   Note:
   If the original time setting did not require adjustment press the green button to move to step 'd'.

4. The temperature setting for period will now be flashing. To adjust this press the or or buttons and confirm the setting again by pressing the green button.
5. The next time and temperature period will now be active. Adjust this by repeating steps b - d above until all 4 periods are set or press the AUTO button to run the program as set, at any time.

Disabling / Enabling Time Periods

The thermostat has 4 periods that can be programmed, but you may not need all of these switch points for your heating requirements. Therefore, any period from 2 to 4 can be removed from (or returned to) the heating program profile.

To disable or enable time periods:

1. To disable unwanted periods go to the desired period ( to ) using the PROGRAM or buttons to navigate, ensure the correct period is highlighted with the flashing square symbol. Press and hold the button for at least 2 seconds and the display will indicate the period has been removed from the program.

2. To enable periods again follow the same procedure as above, navigating to the already disabled period. To enable this period again press and hold the button for at least 2 seconds.

Choosing the Operating Mode

The thermostat can operate in three different modes: Automatic, Manual or Off. To set the operating mode press either of the AUTO, MAN or OFF buttons. The screen indicates which mode is currently active by displaying AUTO, MAN or OFF.

• AUTO (automatic) mode sets the thermostat to follow the built-in temperature program (default or personalised). Operating the thermostat in this mode is the best way to maintain a high level of temperature comfort whilst maximising your energy savings.
• MAN (manual) mode sets the thermostat to act as a simple thermostat with a fixed setpoint throughout the day. The setpoint can be adjusted from 5°C to 35°C by using the or buttons. The thermostat will continue to maintain this temperature until another operating mode or temperature is selected.
• OFF mode sets the thermostat to control to a minimum temperature setting of 5°C (default) that acts as a frost protection measure for your home.

During Normal Operation

• Temperature Enquiry

  In AUTO, MAN and OFF operating modes the thermostat will display the current room temperature. To review the programmed 'target' temperature (the temperature which the thermostat is trying to maintain) press the button. This 'target' temperature value will be displayed flashing for 5 seconds before returning to the current room temperature value.

• Temperature Override

  During normal operation (AUTO mode) the programmed temperature can be adjusted manually by pressing the or buttons or the button. The 'target' temperature will be displayed and flash for 5 seconds - during this time the or buttons can be used to modify the set value.

  Note: This temperature override is cancelled at the next programmed temperature change.

Adjusting the Time

To adjust only the time during normal operation use the or buttons to adjust the time and press the green button again to confirm any changes.

Using the Special Features

• SERVICE indicator
  Note: This option only works if activated by your installer.The 'SERVICE' indicator is displayed at set intervals as a reminder that your heating system requires a routine check. Please call your installer to arrange a maintenance visit.
  The 'SERVICE' indicator will remain on the display of the CM721 until it is either reset or disabled by your installer. The CM721 and heating system will continue to operate as normal.
  
• Automatic Summer/Winter Time Change
  The CM721 has a built-in Automatic Summer/Winter Time Change feature that will automatically adjust the clock forward or backward by one hour for 'Daylight Saving Time'. This is carried out on the last Sunday of March and October each year.
• Optimum Start
  Optimum Start is a program which ensures that the optimum temperature conditions are achieved at the required times. This is an Energy Efficiency feature that adjusts the start time of your heating system depending upon how cold it is. For example, on cold days your heating system will be started earlier to ensure that your home is warm when you get up (at the target temperature) and on warmer days the heating system will be started later to save energy. So, if the Optimum Start Feature is used, then the time / temperature settings which are entered into the thermostat should be set to when you want to be warm by and not when you want the heating system to start.

CM721 FAQ's

How do I change the batteries on the thermostat when they run out?

The thermostat constantly monitors the battery power level, which typically lasts for about 2 years before needing replaced. When the power is running low a flashing symbol will be displayed on the screen.
Note:
While changing the batteries your program settings will be stored but you may need to adjust the time settings to be correct.

How do I set one temperature for the whole day?

To operate as a simple thermostat with one temperature throughout the day, select the manual operating mode by pressing the MAN button. Adjust the temperature by pressing the or buttons - this can be set anywhere from 5°C to 35°C in 0.5°C steps. The thermostat will continue to maintain this temperature until another operating mode is selected or the temperature is adjusted.

BDR91 Relay Box Controls Layout

The relay box will normally be found mounted close to the boiler.

What does it mean when the BDR91 relay box green LED is ON?

The green LED indicates normal operation of the radio frequency system. When the green LED is ON the boiler is also ON. When the LED is OFF the boiler is OFF.

When do I need to use the push button?

You should use the push button to control your boiler only when the RF communication is lost (see the Troubleshooting Guide).

TROUBLESHOOTING THE CM721

Symptom	Remedy
Blank Display (Power Loss).	Check batteries are installed by removing the battery cover. Check batteries have been installed in the correct orientation. Replace the batteries.
Display shows flashing symbol.	The batteries in the thermostat are low on power Replace the batteries.
Display shows symbol.	A fault has occurred in your heating system. Remove and re-insert the batteries. If the symbol does not clear after a few minutes contact your installer.
Display shows the word 'SERVICE'	Your installer has set a scheduled maintenance alert period on your CM721 as a recommendation that your heating system should receive a routine inspection. Call your installer to arrange a maintenance visit. Note: The CM721 and heating system will continue to operate as normal.
BDR91 red LED is constantly on or flashing	RF communication lost due to the wrong location of the room unit - Hook the room unit back on the wall bracket where RF communication was reliable. Call installer NOTE: You can control the boiler manually when the RF communication is lost: Press the BDR91 push button to switch the boiler on and off. When the green LED is on – the boiler is on.

Description of the CM727

The Honeywell CM727 is a programmable room thermostat designed to control your heating system efficiently, providing comfortable temperatures when you are at home and energy savings when you are away. The following instructions explain how to program and use the thermostat to provide the most home comfort at the least cost.

Features of the CM727

• Ergonomic user interface featuring an 'OK-button'.
• Large LCD (Liquid Crystal Display) Screen.
• 7-day heating program to match your lifestyle, whilst maximising energy savings.
• 4 independent temperature levels per day (from 5°C to 35°C).
• Holiday button saves energy by letting you reduce the temperature for 1 to 99 days.
• Automatic Summer/Winter Time Change.
• Optimum Start to achieve the right temperature at the right time.
• Built-in Memory holds the user program indefinitely.

CM727 Controls Layout

1. LCD Screen
2. Battery Low Indicator
3. Time Display
4. Burner On Indicator
5. Day Indicator
6. Temperature Display

7. Temperature Change Buttons

8. Temperature Enquiry Button

9. Operating Mode Buttons

10. Green OK Button

11. Battery Compartment

12. Battery Cover

13. Holiday Function Button

14. Program Buttons

15. Copy Day Button

16. Set Date/Day Button

17. Time Change Buttons

SETTING-UP THE CM727

This section shows you how to setup and run the thermostat in 3 simple steps:

STEP 1: Installing the Batteries

Note:
Please follow the instructions in this section only if the thermostat screen is blank (no symbols or digits are displayed). If the room temperature is already displayed move on to Step 2: Setting the Date and Time.

To install the Batteries:

1. Lift up the front cover of the thermostat to reveal the battery cover and product controls.
2. Remove the battery cover by pressing down and sliding out.
3. Insert the 2 x AA LR6 Alkaline Batteries supplied with the thermostat, ensuring the correct orientation.
4. After a short pause the thermostat will display information on the screen and is now ready for use.
5. Replace the battery cover by sliding it firmly back into the front of the thermostat.

STEP 2: Setting the Date and Time

To set the Date and Time:

1. Press the DATE/DAY button to begin setting the date. When you set the date for the first time after the batteries are inserted, the display will show:
   Press the or buttons to set the current day of the month (e.g. d 01 = 1 st day of the month) then press the green button to confirm.
   

2. Press the or buttons to set the current month of the year (e.g. m 01 = January) then press the green button to confirm.
   

3. Press the or buttons to set the current year (e.g. yr 06 = 2006) then press the green button to confirm.
   The date is now stored and the Day Indicator will be displayed under the current day of the week (e.g. 1 = Monday, 2 = Tuesday, etc.)
   

4. Use the orbuttons to set the correct time then press the green button to confirm. Each press of the buttons will change the time by one minute and holding them down will AM change the time slowly at first and get progressively quicker.
   
   Note:
   If this mode is entered accidentally then press the AUTO, MAN or OFF buttons to exit.

STEP 3: Running the Built-in Heating Program

The thermostat is now ready for operation. Press the AUTO button and the built-in heating program will start running.
Note:
The built-in heating program has been designed to provide normal comfort requirements, but if you want to customise the settings please see the next section 'Programming the CM727'.

The Built-in Heating Program

The built-in heating program has 4 temperature level changes per day that can be set between 3.00am and 2.50am the following day - allowing you to maintain the evening temperature after midnight. Each temperature level can be set between 5°C and 35°C, and adjusted in 0.5°C increments. The factory default program for heating is as follows.

Monday to Friday (Day 1 to 5)

Saturday & Sunday (Day 6 & 7)

Reviewing the Heating Program

To review or edit the heating program use the PROGRAM or buttons to navigate between the 4 individual programming periods for that day. Use the DATE/DAY button to step through each day of the week, so the complete 7 day heating program can be reviewed or edited.

Modifying the Heating Program

To change the heating program:

1. Press either of the PROGRAM or buttons to enter the programming mode. The time / temperature settings for period on Monday (Day 1) will be flashing as shown. The active period is highlighted by a flashing square around the numbers at the bottom of the screen and the selected day is shown with the day indicator.
   
2. To adjust the period start time use the or buttons, the 'OK?' indicator will be displayed to confirm the change. Holding the button down will change the time quickly.
   Note:
   If you are pressing the or buttons and the display flashes the next period, it means the next period will be pushed forward.

3. Once the required time is reached press the green button to confirm.
   Note: If the original time setting did not require adjustment press the green button to move to step 'd'.

4. The temperature setting for period on Monday (Day 1) will now be flashing. To adjust this press the or buttons and confirm the setting again by pressing the green button.

5. The next time and temperature period will now be active. Adjust this by repeating steps b - d above until all 4 periods are set for Monday or press the AUTO button to run the program as set, at any time.

6. You now have a choice of how to set the program for the next day:

   1. Press the COPY DAY button to copy Monday's program into Tuesday. The display will go blank apart from the 'non flashing' day indicator, which indicates the day copied and the 'flashing' target day to copy the program to. To accept this day press the green button. To select a different target day press the DATE/DAY button until the 'flashing' day indicator is under the required day, then accept it by pressing the green button.

      Note:
      Once the target day is confirmed it becomes the day that is copied if the COPY DAY button is pressed again.

   2. OR

      Press the DATE/DAY button to move the day indicator to Tuesday (Day 2). The program for that day can then be adjusted by following steps b to e. Programs for the remaining days can be set in the same way, using the DATE/DAY button to move to the next day.

To exit the programming mode select the desired operating mode by pressing the AUTO, MAN or OFF buttons.
Note:
To run the adjusted program select the AUTO mode.

Disabling / Enabling Time Periods

The thermostat has 4 periods each day that can be programmed, but you may not need all of these switch points for your heating requirements. Therefore, any period from 2 to 4 can be removed from (or returned to) the heating program profile.

To disable or enable time periods:

1. To disable unwanted periods go to the desired period ( to ) using the PROGRAM or buttons to navigate, ensure the correct period is highlighted with the flashing square symbol. Press and hold the button for at least 2 seconds and the display will indicate the period has been removed from the program.
2. To enable periods again follow the same procedure as above, navigating to the already disabled period. To enable this period again press and hold the button for at least 2 seconds.

OPERATING THE CM727

Choosing the Operating Mode

The thermostat can operate in three different modes: Automatic, Manual or Off. To set the operating mode press either of the AUTO, MAN or OFF buttons. The screen indicates which mode is currently active by displaying AUTO, MAN or OFF.

• AUTO (automatic) mode sets the thermostat to follow the built-in temperature program (default or personalised). Operating the thermostat in this mode is the best way to maintain a high level of temperature comfort whilst maximising your energy savings.
• MAN (manual) mode sets the thermostat to act as a simple thermostat with a fixed setpoint throughout the day. The setpoint can be adjusted from 5°C to 35°C by using the or buttons. The thermostat will continue to maintain this temperature until another operating mode or temperature is selected.
• OFF mode sets the thermostat to control to a minimum temperature setting of 5°C (default) that acts as a frost protection measure for your home.

During Normal Operation

• Temperature Enquiry

  In AUTO, MAN and OFF operating modes the thermostat will display the current room temperature. To review the programmed 'target' temperature (the temperature which the thermostat is trying to maintain) press the button. This 'target' temperature value will be displayed flashing for 5 seconds before returning to the current room temperature value.

• Temperature Override

  During normal operation (AUTO mode) the programmed temperature can be adjusted manually by pressing the or buttons or the button. The 'target' temperature will be displayed and flash for 5 seconds - during this time the or buttons can be used to modify the set value.
  Note:
  This temperature override is cancelled at the next programmed temperature change.

Adjusting the Time

To adjust only the time during normal operation use the or buttons to adjust the time and press the green button again to confirm any changes.

Using the Special Functions

• HOLIDAY Function

  The holiday function allows you to set a constant temperature (default = 10°C) for a specified number of days (from 1 - 99 days). This lets you save energy and related costs when you are away from home, but resumes normal operation on the day of your return.

  To set the Holiday function:

1. Ensure the thermostat is running in AUTO or MAN operating modes.
2. Press the holiday button to display the holiday days counter and temperature setting, along with the holiday indicator .
3. Press the or time buttons to set the holiday time (1 - 99 days) and press the green button to confirm.
4. Press the or buttons to set the holiday temperature (5°C - 35°C) and press the green button to confirm.

The thermostat will now control to the new temperature for the set number of days that your home is vacant. At midnight the holiday counter will be reduced by one until the selected number of days have passed. The thermostat will then return to normal operation as set by the MAN or AUTO mode. To cancel the HOLIDAY function or to exit the function at any time press the button a second time.

Using the Special Features

• SERVICE indicator (optional)
  Note: This option only works if activated by your installer.
  The 'SERVICE' indicator is displayed at set intervals as a reminder that your heating system requires a routine check. Please call your installer to arrange a maintenance visit.
  The 'SERVICE' indicator will remain on the display of the CM727 until it is either reset or disabled by your installer. The CM727 and heating system will continue to operate as normal.
• Automatic Summer/Winter Time Change
  The CM727 has a built-in Automatic Summer/Winter Time Change feature that will automatically adjust the clock forward or backward by one hour for 'Daylight Saving Time'. This is carried out on the last Sunday of March and October each year.
• Optimum Start
  Optimum Start is a program which ensures that the optimum temperature conditions are achieved at the required times. This is an Energy Efficiency feature that adjusts the start time of your heating system depending upon how cold it is. For example, on cold days your heating system will be started earlier to ensure that your home is warm when you get up (at the target temperature) and on warmer days the heating system will be started later to save energy. So, if the Optimum Start Feature is used, then the time / temperature settings which are entered into the thermostat should be set to when you want to be warm by and not when you want the heating system to start.

CM727 FAQ's

How do I change the batteries on the thermostat when they run out?

The thermostat constantly monitors the battery power level, which typically lasts for about 2 years before needing replaced. When the power is running low a flashing symbol will be displayed on the screen.
Note:
While changing the batteries your program settings will be stored but you may need to adjust the time settings to be correct.

How do I set one temperature for the whole day?

To operate as a simple thermostat with one temperature throughout the day, select the manual operating mode by pressing the MAN button. Adjust the temperature by pressing the or buttons - this can be set anywhere from 5°C to 35°C in 0.5°C steps. The thermostat will continue to maintain this temperature until another operating mode is selected or the temperature is adjusted.

BDR91 Relay Box Controls Layout

The relay box will normally be found mounted close to the boiler.

What does it mean when the BDR91 relay box green LED is ON?

The green LED indicates normal operation of the radio frequency system. When the green LED is ON the boiler is also ON. When the LED is OFF the boiler is OFF.

When do I need to use the push button?

You should use the push button to control your boiler only when the RF communication is lost (see the Troubleshooting Guide).

TROUBLESHOOTING THE CM727

Symptom	Remedy
Blank Display (Power Loss).	Check batteries are installed by removing the battery cover. Check batteries have been installed in the correct orientation. Replace the batteries.
Display shows flashing symbol.	The batteries in the thermostat are low on power Replace the batteries.
Display shows symbol.	A fault has occurred in your heating system. Remove and re-insert the batteries. If the symbol does not clear after a few minutes contact your installer.
Display shows the word 'SERVICE'	Your installer has set a scheduled maintenance alert period on your CM727 as a recommendation that your heating system should receive a routine inspection. Call your installer to arrange a maintenance visit. Note: The CM727 and heating system will continue to operate as normal.
BDR91 red LED is constantly on or flashing	RF communication lost due to the wrong location of the room unit - Hook the room unit back on the wall bracket where RF communication was reliable. Call installer NOTE: You can control the boiler manually when the RF communication is lost: Press the BDR91 push button to switch the boiler on and off. When the green LED is on – the boiler is on.

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 document. 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, Switzerland by its Authorised Representative Honeywell Inc.

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