Other features, Wiring diagrams troubleshooting – Comfort Stat CP1820 User Manual

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H OLD

CLEAR

HOLD

CLEAR

DAY

HOUR

HO LD

CLEAR

HO LD

CLEAR

FOR WINTER

NUMBER

PROGRAM

MONDAY

TIME
TEMP

TUESDAY

TIME
TEMP

WEDNESD
AY

TIME
TEMP

THURSDAY

TIME
TEMP

FRIDAY

TIME
TEMP

SATURDAY

TIME
TEMP

SUNDAY

TIME

TEMP

TIME

TEMP

TIME

TEMP

TIME

TEMP

FOR SUMMER

NUMBER

PROGRAM
1

PROGRAM
2

PROGRAM
3

PROGRAM
4

MONDAY

TIME
TEMP

TUESDAY

TIME
TEMP

WEDNESD
AY

TIME
TEMP

THURSDAY

TIME
TEMP

FRIDAY

TIME
TEMP

SATURDAY

TIME

TEMP

TIME

TEMP

TIME

TEMP

TIME

TEMP

SUNDAY

TIME
TEMP

Programming Your Thermostat

Your thermostat can be programmed in two different ways.

1. Autoprogram method 2. Manual method

Before programming, position the HEAT/OFF/COOL selector to be programmed.

Auto Programming

Our thermostat is preprogrammed guidelines for energy efficiency. Note that it is easier

to modify these programs than to programs than to program the thermostat manually.

■ Press once. During Auto Programming, the display

will change as shown.

■ The thermostat will be programmed for all 7 days of

the week as shown below.

Temperature in ˚F/℃

Program Number

Time

Heat

Standard

6:00am

68 ˚F (20℃)

78 ˚F (26℃)

8:00am

60 ˚F (16℃)

85 ˚F (29℃)

4:00am

68 ˚F (20℃)

78 ˚F (26℃)

10:00am

60 ˚F (16℃)

85 ˚F (29℃)

■ Refer to Manual Programming entering or changing the programs.

Manual method

In this method, each program is inserted according to your personal programming

schedule.

Familiarize yourself with manual programming. The following example demonstrates the

manual programming method. You can program or change the program of weekdays,

weekends, or individual days.

NOTE:1) The program time is set in increments of 15 minutes.

2) The program temperature is set in increments of 1℉.

3) When setting PM time, make sure the “PM” indicator appears on the display.

Weekday Programs

Press Display Reads

■ Normal display of time, temperature,

and day of the week.

Step 1

■ Selects days Mon to Fir for same set of 4

programs each day.

Step 2

■ Program indicator(1) is displayed.
■ 68℉ is displayed.

■ Mon to Fir is displayed.

Step 3

■ Press and hold until 6:00 is displayed.
■ Note AM/PM

Step 4

■ Press once to change temperature to 69℉.
■ Weekday program 1 is complete.
■ Press PROG to move to program 2,3, and 4

and follow the same steps.

Use to insert or change time and temperature

of other programs.

■ Selects weekend days Sat, Sun for same

set of 4 programs each weekend day.

■ Follow steps 24 to enter programs.

Similar to weekday programming.

to insert weekend programs.

Individual Day Programming

To program for each individual day separately by a different set of programs, first select

day by displaying the day of program, then insert the desired times and temperatures.

Press Display Reads

■ Mon to Fir are selected. Mon to Fir will have

Same programs.

■ Sat to Sun will have

Same programs.

■ Mon is selected, program for Mon only.

Use to enter programs for Monday.

Similarly Tue to Sun can be selected.

Display the day to be programmed and use

to enter programs.

NOTE: Another approach to programming is to first program all weekdays Mon

through Fir and Sat and Sun as same programs. Then, display and change the

programs of only those days which will have different programs.

Reviewing Programs

You may want to review the programs to see that the settings are compatible with your
lifestyle.

■ Normal display of current time, day of week

temperature, and day of week.

■ 1st weekday program is displayed.
■ Program indicator(1) appears.
■ Mon to Fri indication appears.

■Continue pressing

to view each day.

■Continue pressing

to view each period.

If you are armchair programming the thermostat, before you mount the face of the

thermostat, turn the system selector to the OFF position.

Temporary Manual Override
To temporarily change the current set temperature without affecting your program:

Press

and to change to your desired new

temperature.

■Press to RUN to normal mode, or wait 15 seconds for it

to return automatically.

■The current program number will flash to signify the Temporary Override. At

the next program change, the Temporary Override, and the next program

temperature becomes the set point temperature.

To end the Temporary Manual Override:

■Press and wait for HOLD to display on the lcd.
■Press HOLD key. This will return the set temperature to the current program

set temperature.

Permanent Override or a Designated Day Override

To hold your Manual Override for vacation or Until a Designated

Day

■ Press to make the current program temperature

the HOLD temperature. HOLD will be displayed on

the LCD, and the Program number will disappear.

■ Follow the Temporary Manual Override instructions above to change the

Permanent Manual Override temperature.

■ You can confirm the held set temperature by pressing for less than 1

second.

■ Press again. Hold day will be displayed on the lcd

and the clock will disappear

■Press Day key to add override days.

Press Hour key to reduce override days

■ Follow the Temporary a Designated Day

Override instructions above to change the Permanent Manual

Override

temperature.

To end Override:

Under Permanent Override Press hold/return key twice. Under a Designated Day

Override press the hold once. The thermostat will return to the current program, and the

HOLD display will be canceled.

Other Features

12Hr. / 24 Hr. Time Format

Your thermostat is set from the factory in normal 12 (AM/PM) time format. To change to

24 hour (military) time, press during time and day setting mode to toggle

between the 12 hour and 24 hour formats. The AM / PM indicator will not be displayed

in 24 hour mode. Both the current time and all programs will automatically change to

the selected format.

Backlighting

Your thermostat has an electroluminescent lamp that backlights the display for easy

viewing in the dark.

When any key is pressed the display is illuminated.

The display will remain illuminated for 8 seconds after the last key is pressed. This

allows the light to stay on if you need to operate several keys.

Note: If the thermostat is in Low Battery warning condition, the backlight will not operate.

Replace with 2 new AA alkaline batteries to restore the Backlight function.

Filter Monitor

Your thermostat also keeps a record of the number of hours your

filter has been in use. To maximize your system’s performance and

energy efficiency, change or clear your filter regularly.

When the total system run time for heat and cool reaches 400 hours,

you need clean or change your system’s filter, “FILT” will continue to

flash until the counter is set back to zero.

■ Press to review total filter usage. The display will blink “FILT”

Then show the filter Monitor counter. After 15 seconds, the display

will return to normal mode, or you can hit RUN to exit immediately.

The Filter Monitor will display up to 999 hours and 59 minutes of usage. In this example,

the counter is at 410 Hours, 26 minutes.

■ To reset the Filter Monitor counter, depress FILTER for 3 seconds. The display will

blink, and The counter will be reset to zero.

Auto Recovery

Auto Recovery calculates how early to turn you system back on, so that the room

temperature is already comfortable by the start of the comfort

temperature program period. Auto Recovery work’s in both Heat

and Cool modes.

■When the thermostat is in Auto Recovery mode, the display will

alternate “RECO” with time, and the program indicator will flash.

■Auto Recovery can be disabled by sliding the Recovery switch on the circuit board to

disable.

■Auto Recovery will not operate if Permanent hold or Temporary hold is in operation.

■Auto Recovery can be canceled manually if HOLD is pressed during the recovery

process.

■Auto Recovery will be canceled and change to next period.

Details of Auto Recovery Operation:

■ Auto Recovery can be disabled by sliding the Recovery switch on the circuit board to

this position.

■ Auto Recovery will not operate if Permanent hold or Temporary hold is in operation.

■ Auto Recovery can be canceled manually if HOLD is pressed during the recovery

process. If a recovery process is canceled manually then the recovery process will not

start again until the next program period starts (an exception is that if time or program is

changed then the thermostat will check Auto Recovery conditions immediately).

Error Mode

If the thermostat is unable to control your system due to an

unexpected battery problem, the thermostat will enter Error Mode.

In this condition, the thermostat flashes “E1”or “E2”on the LCD

display, and shuts off your system. To correct this problem,

replace the batteries with 2 new AA alkaline batteries, even if you

have recently replaced them. Move the battery out hold any key

then place the battery again. You will need to reprogram your

thermostat and confirm normal operation.

Lcd display

information

Lcd display

information

Sensor Error

System switch

Low Battery Warning

Your thermostat has a twostage lower battery warning system. When the batteries are
first detected to be weak, the first stage low battery warning is indicated

by “BATT” flashing on the LCD display. At your earliest
convenience, you need to replace the batteries with 2 new AA

alkaline batteries.
When the batteries become too weak for normal operation, the

thermostat enters the second stage low battery warning which
shuts down the thermostat. In this condition, “BATT” flashes alone

on the display, and the thermostat will turn your system Off. Your
system will remain shutoff until the batteries are replaced.

NOTE: The thermostat will still keep the current Set Temperature and Filter run time in
memory until new batteries are installed. After confirming that new batteries have been

inserted, the thermostat will return to normal operation.

Wiring Diagrams

Troubleshooting

Problem

Solution

SCRAMBLED OR DOUBLE DISPLAY 1. Remove clear mylar sticker.

(numbers over numbers)

NO DISPLAY

1.Check battery connections and batteries.
2.Move the battery out, and then hold any key to

release the rest energy. Then place the battery
again.

ENTIRE DISPLAY DIMS

1.Replace batteries.

PROGRAM DOES NOT CHANGE

AT YOUR

1.Check that time is set properly to “AM” or “PM”

DESIRED SETTING

2.Check that thermostat is not in “HOLD” mode.
3.Check for correct day setting.

AUTO/FAN DOES NOT COME ON

1.Move HG/HE system selector to opposite

Position.

HEATING OR COOLING DOES NOT GO ON OR OFF

1.Check that function switch is in correct

position (“HEAT” or “COOL”).

2.There may be as much as 20 seconds delay

before the system turns on – wait and check .

3.Check your circuit breaks and switches to ensure

there is power to the system.

4.Replace batteries.
5.Make sure your furnace blower door is closed

properly.

6.If your system only uses 4wires, be sure the

jumper wire is installed between the RC and RH
terminals.

ERRATIC DISPLAY

1.Move the battery out, and then hold any key to

release the rest energy. Then place the battery
again.

IF UNIT CONTINUES TO OPERATE 1.Replace unit.
IN OFF POSITION

THERMOSTAT PERMANENTLY

1.Replace unit.

READS “HI”, “LO”, OR “E1”,“E2”..

If you experience any other problems, call us for technical assistance.

The service number is 18665919898

HOUR

DAY

PROG

DAY

PROG

HOUR

MIN

DAY

PROG

DAY

PROG

DAY

PROG

AUTO
PROG

DAY

PROG

HOUR

MIN

DAY

PROG

HOUR

MIN

DAY

PROG

R U N

12/24

HO URS

HOUR

MIN

PROG

DAY

PROG

THERMOSTAT

120V
AC

AC24V