Honeywell CT1957, CT1950 specifications Specifications, Installation, Wiring

	CT1950/CT1957
	Chronotherm ™
	Electronic
	Programmable
	Line Voltage
	Thermostat
Your CT1950/CT1957 Programmable Electronic Line	Contents
Voltage Thermostat features digital temperature
	Specifications	. 2
sensing and control for energy efficient
	Installation	. 3
precision operation. It will provide the flexibility
	Wiring	. 4
of 5-1-1 day or 7 day programming and
	Thermostat Programming	. 6
exceptional comfort control of resistance-rated
	Initial Power-Up	. 6
heating equipment.The patented CoolSwitch™
design offers long service life.	Clock	. 7
	Schedule: 7 days	. 8
Depending on local climate, night and day set-
	5-1-1 days	12
back of space temperature can save up to 28%
of the energy used to heat a controlled zone.	Reset	. 6
	Additional Functions	11
According to the Electric Power Research
	Change Display	11
Institute, precision temperature control also offers
up to 12% energy saving during comfort periods	Temporary Program Override	13
compared with conventional bi-metallic electric	Indefinite Program Override	13
heating thermostats.	Copy Program From One Day to Another . .	10
	Checkout	14

SPECIFICATIONS

MODELS: CT1950A/CT1957A - SPST; Makes heating circuit on temperature fall.

CT1950B - DPST; Makes heating circuit on temperature fall. Breaks both sides of 240 volt line with switch in "OFF" position.

Operating range: -20 to +104°F [-30 to +40°C], 5 to 95% RH, non-condensing.

CONTROL RANGE:

7 to 27°C [45 to 80°F] in 1° increments. Factory set at 16°C [61°F] .

SWITCHING:

Patented CoolSwitch™ thyristor with relay conductor.

WIRING CONNECTIONS:

6" [150 mm] stranded copper leadwires suitable for connection to aluminum wiring if approved special service CO/ALR connectors are used.

ELECTRICAL RATINGS, NON-INDUCTIVE:

16 A (3800W) maximum, 2 A (500W) minimum @ 240V, 60 Hz. (12 ft. of baseboard maximum)

SENSING ELEMENT:

Electronic thermistor.

2

5			Display MINUTE of the Day
6			Change MINUTE of the Day
THERMOSTAT PROGRAMMING – TEMPERATURE SETUP 7 Day Mode (factory default setting)
Step	Press This Key	Display will look like this	Description
			Scroll through to display showing the first
7			day of programming [beginning with
			MOnday]
8			Display WAKE time
Note; Broken line outline indicates flashing characters		8
Step	Press This Key	Display will look like this	Description
9			Change WAKE time in 10 minute
			increments
10			Display WAKE setpoint temperature
11			Change WAKE setpoint temperature
12			Display LEAVE time.
			Repeat the adjustments suggested in
			steps 9 - 11 for the LEAVE, RETURN and
			SLEEP periods
		9
COPY FROM – AND COPY TO – ANOTHER DAY
Step	Press This Key	Display will look like this	Description
			Select and display the day to be copied,
13			e.g. MOnday
			Press key to display COPY FROM
14
15			Select and display TUesday program period
			(pressing key will display COPY TO)
			Finally, press FUNC to enter this
16			program.
			Repeat process for each day copied
Note: To exit the programming mode at any time, press		10	Broken line outline indicates

and hold the PROG key for 3 seconds. flashing characters

INSTALLATION

!WARNING

•This thermostat is a line voltage (240 Vac) control. Do not install it unless you are completely familiar and competent with house wiring. If improperly handled, there can be a risk of 240 Volt electric shock hazard which may cause serious injury or death.

•The CT1950/CT1957 is rated for normal full load current on a dual residential 20 A circuit breaker or fuse block. Do not use on circuits protected by higher-rated over-current protection devices. Some sustained fault conditions can cause product failure.

•Do NOT connect to voltage different from device rating.

!CAUTION

•Disconnect power supply before making wiring connections to prevent electrical shock or equipment damage.

•All wiring must comply with applicable codes and ordinances.

•Thermostats are designed to be used with appliances having a limit control.

•Maximum load for thermostat must not exceed 3800W, otherwise a potential fire hazard exists. (ie. greater than 12 ft. of baseboard)

LOCATION:

Install a vertical switch box for mounting the CT1950/CT1957 approximately 1.5 m (5 ft.) above the floor on an inside wall where the thermo stat will be subjected to average room temperature. The thermostat must be placed away from concealed warm or cold water pipes,

air ducts, or drafts from hallways, fireplaces or stairways to sense temperature properly. Do not place thermostat above heater.

3

THERMOSTAT PROGRAMMING – ADDITIONAL FUNCTIONS

To change display	FF	FF	Press and hold both the PROG and FUNC
17			keys. Initially a random 4 digit/letter
			display will occur.
		36	Press PROG key and continue –
18			(“b” will appear for b model only).
Convert to			Press PROG key a second time to
°C or °F
19			display C°. Use [+] key to change to
			F° if desired (or F° to C°)
Convert 5-1-1			Press PROG key a third time to
to 7-day			display “5 1 1 d”; press [+] key to
20			change mode to 7-day programming
			(or vice versa)
	11
PROGRAMMING ADDITIONAL FUNCTIONS cont’d

WIRING:

1. Disconnect power while installing.

Double check that thermostat is rated for voltage and amperage of load to be controlled.

2. Remove cover as needed by carefully prying at the top or bottom edge with a coin or slot screwdriver.

Fig. 1 Wiring
1	Power supply. Provide disconnect means	(A)				(B)
	and overload protection as required.	L2			2	L2
2	Special service CO/ALR solderless
	connections must be used when	1				1
	connecting aluminum conductors;			3		L1
	otherwise, a fire hazard may result.
		L1		L1		BLACK
			BLACK			CT1950B

3	Thermostat breaks heating circuit on	CT1950A/
	temperature rise.		T 1
		CT1957A	4
4	Thermostat is designed to be used with
	appliances equipped with a limit control.		ELECTRIC
		BLACK
5	B Model thermostat breaks both sides of		HEATER
	line with switch in OFF position

4

2

BLACK

5L2

L1

T2

3T 1

RED RED

4

ELECTRIC HEATER

PROGRAMMING: 5-1-1 Day Mode (refer to steps 17-20)
Press This Key	Display will look like this	Description
		Scroll through the displays until the
		screen shows the MOnday to FRiday
		schedule with the WAKE, LEAVE
		RETURN and SLEEP options
		Follow the same programming
		proceedure as steps 8–12

Program SAturday and SUnday separately or use the “Copy From – Copy To” feature (steps 13–16)

cont’d

line outline indicates flashing characters 12

WIRING cont’d

3.When replacing an old line voltage wall thermostat, remove it carefully to avoid damage to the insulation on the wiring. Check the old insulation for cracks, nicks, or fraying and apply certified electrical tape where necessary to achieve adequate insulation, or replace the wires in an approved fashion.

4.Attach wires with solderless wire connectors approved for the size and number of wires to be connected. Be sure that all wire connectors are tight.

CAUTION: Do not short 240 V supply wires with thermostat connected. This will damage the CT1950/CT1957 and void the warranty.

!WARNING: To avoid risk of fire hazard, all connections to aluminum conductors must be made using approved CO/ALR solderless connectors.

5.Secure thermostat to the electrical box with captive mounting screws. Installation Hint: Prebend the solid conductors, then push them and the wire connectors into the electrical box before tightening the mounting screws.

6.Snap cover in place.

7.Turn power on.

5

TO INDEFINITELY OVERRIDE A PROGRAM

Step	Press This Key	Display will look like this	Description
24			Press and release FUNC key to activate
			the HOLD mode.
			Press and hold PROG key to return to
			RUN mode.

TO TEMPORARILY OVERRIDE A PROGRAM

	Press and hold [+] or [-] key until TEMP
25	appears on screen; adjust temperature [+] or
	[-] as desired. Thermostat will return to normal

program status automatically in next period

13

THERMOSTAT PROGRAMMING INITIAL POWER-UP

CHECKOUT

On first power up, the thermostat display will show a self test

status, 00 Edisplay for about 15 seconds, then go blank for one second, followed by this display —

(broken line indicates section is flashing.)

The thermostat will begin temperature control with the default setpoint at 61°F

(16°C) in the HOLD mode. It will continue to operate in this manner until the user presses PROG and proceeds to set the clock (Step 1) below.

Note: To Change display or functions (e.g. to °C or °F, or programming from 5-1-1 to 7-day) see instructions on Additional Functions, p. 11.

FACTORY SET PROGRAMMING

The thermostat is preset with a factory set schedule for 7

days (see Table 1 below). After the clock is set up, if the factory set schedule is satisfactory, no more programming is required. The thermostat will revert to normal RUN mode either by pressing and holding the PROG key for 3 seconds, or left untouched for 5 min- utes.

Table 1 – Initial Factory Schedule for 7-day
Event	Time	Temperature
WAKE	6:00 a.m.	21°C (70°F)
LEAVE	8:00 a.m.	16°C (61°F)
RETURN	6:00 p.m.	21°C (70°F)
SLEEP	10:00 p.m.	16°C (61°F)

THERMOSTAT RESET The reset key is accessed by inserting a bent paperclip or similar wire into the small hole next to the [+] key (with cover removed). This will reset the clock only, programmed schedule will be retained.

6

When the thermostat is first powered up (or after 8 hours of continuous power loss), the display will blink for 2 seconds, then undergo a self test, indicated by OOE for 15 seconds. Once the display shows 1:00 pm flashing, the internal checkout is complete, and the thermostat is ready to program.

To verify the thermostat is turning on the baseboard heater, repeatedly press the [+] key until the displayed setpoint exceeds the room temperature. The [°] symbol should be flashing. Feel near the baseboard heating element and the unit should be starting to generate heat.

Press and hold the PROG key and the thermostat will return to its former RUN mode.

TROUBLE SHOOTING

Display Code	Cause	Action
OLOAd	Connected load exceeded	Ensure that total wattage of baseboard connected do not exceed 3800W.
	3800W	A fire hazard exists if wattage exceeds 3800W. Push reset key to clear
		and reset clock.
06E	Power failure detected	Push reset key to clear and reset clock.
Missing segment or other abnormal display		Push reset key to clear and reset clock. If problem persist call Honeywell.
		14

THERMOSTAT PROGRAMMING CLOCK SETUP

Step	Press This Key	Display will look like this	Description
1			Display DAY of the Week
2			Change DAY of the Week
3			Display HOUR of the Day
4			Change HOUR of the Day
		7

Automation and Control Solutions

Honeywell	Honeywell Limited-Honeywell Limité e
1985 Douglas Drive North	35 Dynamic Drive
Golden Valley, MN 55422	Scarborough, Ontario
	MIV 4Z9

G.H. • 6/02 • © Honeywell Limited 69-1644EF