Honeywell cm921 User Manual

CM921

WIRELESS PROGRAMMABLE THERMOSTAT

PRODUCT SPECIFICATION SHEET

The CM921 thermostat is designed to provide automatic time and temperature control of heating or cooling systems in villas and apartments.

It can be used as part of a system in conjunction with combiboilers, oil-burners and gas fired boilers, circulation pumps, thermal actuators, zone values and electric heating systems (<10A). In combination with other CM921 room units and HC60NG receivers it can be used to control multi-zone applications (up to 4 zones).

The radio frequency controlled CM921 system pack consists of a room unit CMT921A and a relay box R6660D (HC60NG). No wiring to the room unit is required. The installer only needs to wire the relay box to the controlled device (e.g. boiler) and mount the room unit in a suitable location where RF communication is reliable. The CM921 uses reliable RF communication technology in the 868MHz band.

The CM921 extra large LCD display, dynamic text display and controls layout are identical to the CM901 ‘wired’ thermostat. The unit is ideal for consumers who want reliable and precise temperature control from a modern looking, simple to program and easy-to-use product.

FEATURES

•CM921 can be installed without disrupting your room décor as no wiring connection is required between the room unit and the boiler

•Attractive, slim, ultra-modern styling makes it ideal for location in any type of home

•1-day heating programming

•A dynamic text display on the LCD that gives enhanced feedback to the user / installer

•LCD Backlighting to illuminate the display for easier viewing in low light conditions

•Reliable RF communication utilising 868 MHz band with 1 % duty cycle limit to minimise communication disturbance

•Every room unit can be bound with several relay boxes (e.g. to control several electric heating panels)

•Armchair programmed

• Holiday button that provides energy savings by reducing to a constant temperature for 1 to 99 days when people are on holiday, returning to normal operation (AUTO or MANUAL) on the day of their return.

•EEPROM memory holds the user program indefinitely

•OFF position has an integral frost protection setting at minimum 5°C (installer adjustable) so that pipes in the house will never freeze in winter.

•Communication compatibility with other Honeywell product such as HR80, HM80 and HCE80.

•CM921 can be used to control a zoning system with up to 4 zones

•Maximum system efficiency and extended boiler life due to unique zoning system synchronisation

•Automatic Summer / Winter time change adjusts the time automatically to daylight saving time.

•Standard room units and receiver boxes are used for zoning applications algorithm

•When used with the table top stand the room unit can be positioned anywhere in the room where RF communication is reliable

•24...230V 10A resistive, 3A inductive SPDT relay provides compatibility with most domestic central heating systems reducing the need to stock many different models.

•The HC60NG may be surface or wallbox mounted.

•Installer Set-Up Mode allows extra functions to be set at the discretion of the installer to match the consumer applications and needs:

•Optimisation

•Pump Exercise

•Upper / Lower Setpoint Limit Adjust

•Temperature offset

•Minimum ON time

•Cycle rate

•Heat / Cool Operation

•Proportional Band Width

•Fail-safe mode for communication loss

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Operating temperature

CM921 CHRONOTHERM

CONTROLS/DISPLAY LAYOUT

Room Unit Layout:

1.Day & Date Display

2.Time Display

3.Dynamic Text Display (DTD)

4.Burner On Indicator

5.Battery Low Indicator

6.Temperature Display

7.Temperature Change Buttons

8.Information Enquiry Button

9.Slider Switch

10.Green OK Button

11.Program Buttons

12.Battery Cover

13.Battery Compartment

14.Holiday Button

15.Time Change Buttons

SPECIFICATIONS

ELECTRICAL

Room unit power : 2 x 1.5 V IEC LR6 (AA) Alkaline cells supply

Battery life	: Minimum 2 years
Battery	: Program retained in EEPROM
replacement
Receiver power	: 230V AC +10% - 15%, 50Hz
supply
Switch type	: SPDT potential free
Output rating	: 24-230 V AC, 10 A resistive, 3 A inductive
	0.6 p.f.
Wiring (receiver	: Cable terminals for mains and relay wiring
only)	for max 2.5 mm2 wire
Wire access	: from the rear (wall box mounting), right
	and bottom

RF

RF operation band : ISM (868.0-868.6) MHz, 1% duty cycle

RF communication : 30 m in a residential building environment range

RF communication : short, high rate transmissions to minimise technology air time and avoid collisions

Blocking immunity : Receiver class 2 (ETSI EN300 220-1 version 1.3.1)

RF binding method : Factory pre-bound with the room unit.

ENVIRONMENTAL & STANDARDS

: 0 to 40oC when relay load < 8 A

: 0 to 30oC when relay load > 8 A

Shipping & storage : -20 to 55oC temperature

Humidity	: Humidity range 10 to 90% rh, non-
		condensing
IP class	:	30
Meeting the	:	EN60730-1(Nov 2000), EN55014-1(1997),
following		EN55014-2(2000), ETSI EN300 220-3
standards		(2000), ETSI EN301 489-3(2000)

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TEMPERATURE CONTROL

Sensing element	:	100K (@ 25 oC ) NTC thermistor
Control form	:	Fuzzy Logic Algorithm
Minimum ON		10% of cycle time (min one minute),
time		adjustable to 2 to 5 min (see installer set
		up)
Cycle rate	:	Selectable by application (see installer
		set up)
Temperature	:	+0.5 K (nominal) @ 20oC, 50% load 3K
control accuracy		/hour
Fail-safe mode	:	Off or cycling depending on the CM927
		system set-up

TIME SETTING/PROGRAMMING

Time display	: 24 hour or 12 hour AM/PM format
Time keeping	:	Typically better than 10 minutes per year
accuracy
Program	: 1-day with 6 daily time and temperature
		level changes
Time setting	: Time of day - 1 minute
resolution		Program – 10 minute steps
Temperature	:	Program : 5 to 35oC in 0.5 oC steps Frost
setting range		: 5 oC or equal to lower limit (5
		oC to 16 oC). Frost protection does not
		work in cooling mode
Room	:	From 0 oC to 50 oC
Temperature
display range

CM921 CHRONOTHERM

INSTALLER SET-UP

To enter the installer set-up mode:

a)Move the slider switch to the OFF position.

b)Press and hold the INFO i button and the two program buttons ‘< >’ together.

c)The unit will display the first parameter of installer parameter group category 1 (from n.1 to n.19).

d)Press the TEMP or buttons to change the factory setting. The display will flash indicating that a change has been made.

e)Press the green OK button to confirm this change and the display will stop flashing.

f)Press the + button to go to the next parameter.

g)Press the program button > to go to category 2 in the Installer mode (from n.1 to n.14).

h)To exit the installer mode, move the slider switch to the AUTO or MAN positions.

In Installer set-up we can:

Set-up specific applications parameters

Enable special features

Configure system timing master for the zoning system

Abbreviated Set-Up Description

e.g. Cl = Clock Format

Installer Set-up Number

(Press + or - to change) e.g. 1 = Clock Format

Factory Setting or New Choice

Press TEMP or to change e.g. 12 = AM/PM Format 24 = 24hr Format

Brief Description of the

Parameter Function.

Specific Applications		Setting		What do you need to change?
		Cycle/	Minimum	Note : All parameters listed below belong to category 2 – System
		Hour	ON time	Parameters (see Installer Parameters Table)
			(in minutes)
Heating	Gas Boilers	6	1	No changes required
	(<30KW)
	Oil Boiler	3	4	1.	Set Minimum ON Time to 4 minutes.
				2.	Set Cycle/Hour to 3.
	Thermal Actuator	12	1	Set Cycle/Hour to 12.
	Zone valve	6	1	No changes required.
Air				1.	Configure the thermostat to allow switching between heating
conditioning					and cooling modes (set parameter n.4:HC to 1)
				2.	Set the thermostat accordingly to the required mode of
					operation (heating or cooling) by pressing the TEMP	or
					buttons together for 5 seconds. Modify the cooling program
					as required.
	Heat Pump/	3	4	1.	Set Minimum ON Time to 4 minutes.
	Air conditioner			2.	Set Cycle/Hour to 3.
	Fan coil	6	1	No changes required.

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