Saswell T21STK-2 User manual

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OPERATING
T21STK-2
INSTRUCTION

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T21STK-2 SINGLE STAGE PROGRAMMABLE THERMOSTAT
1 Heat / 1 Cool single stage thermostat.
5+2 Programmable, Compatible with heat pump system
Installation and Operation Manual
Specification:--------------------------------------------------------------------------------
Power Supply: 20VAC-30VAC 50-60HZ or Battery powered.
Terminal Load: 1.0A per terminal, 3.0A maximum total load
Set Point Temperature Range: 45ºF to 90ºF (7ºC to 32ºC).
Accuracy: +/- 1ºF or +/- 0.5ºC.
Dimensions: 6.0” W X 4.7” H X 1.1” D
Color: White

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FEATURES:---------------------------------------------------------------------------------
Large LCD display with backlight, continuous backlight option
Simultaneous heat and cool set point storage
Display of room temperature, set temperature and current time simultaneously
Fan switch with ON and AUTO
Permanent user setting retention during power loss. No batteries are required.
Operates from 24VAC, or from 2 size “AA” alkaline batteries
Optional temperature display of Fahrenheit or Celsius scale.
Air Filter change Indicator
Low Battery Indicator
Display temperature calibration.
Separate 5-day (weekday) and 2-day (Saturday/Sunday) programming with

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four separate time/temperature periods per day.
Intelligent Recovery Option for optimizing comfort
IMPORTANT SAFETY INFORMATION-------------------------------------------
Always turn off power at the main power source by removing the fuse, or
switching the circuit breaker to the off position before installing, removing,
cleaning, or servicing this thermostat.
Read all of the information in this manual before installing this thermostat.
Use a professional contractor to install this thermostat.
This is a 24VAC low-voltage thermostat. DO NOT INSTALL ON VOLTAGES
HIGHER THAN 30 VAC.
ALL wiring must conform to local and national building and electrical codes
and ordinances.

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Do not short (jumper) across terminals on the gas valve or at the system
control to test installation. This will damage the thermostat and void the
warranty.
Do not switch the system to cool if the temperature is below 50ºF (10ºC). This
can damage the air conditioning system and may cause personal injury.
Replace batteries when the battery icon indicates the low battery message.
Change the Air Filter when the Filter Change Icon begins blinking.
Use this thermostat only as described in this manual.
REMOVE THE OLD THERMOSTAT--------------------------------------------------------------------------
WARNING!: Electrical Shock Hazard
1. Turn off power at the main service panel by removing the fuse or switching the
appropriate circuit breaker to the OFF position before removing the existing
thermostat.

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2. Turn off power to the heating and cooling system by removing the fuse or
switching the appropriate circuit breaker off.
3. Remove the cover of the old thermostat. This should expose the wires.
4. Label the existing wires from the existing thermostat before removing.
5. After labeling the wires, remove the wires from the wire terminals.
6. Remove the existing thermostat from the wall.
7. Refer to the following section for instructions on how to install this thermostat.

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INSTALL THE THERMOSTAT---------------------------------------------------------------------------------
ATTACH THERMOSTAT BASE TO WALL PULL THE COVER OFF THE BASE.

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WARNING!: Electrical Shock Hazard
Turn off power at the main service panel by removing the fuse or switching the
appropriate circuit breaker to the OFF position before removing the existing thermostat.
1. Turn off power to the heating and cooling system by removing the fuse or
switching the appropriate circuit breaker off.
2. Place the system switch (COOL/OFF/HEAT) in the OFF position.
3. Place the FAN (AUTO/ON) switch in the AUTO position.
4. Gently pull the cover straight off the base. (See figure 1.)
5. Put the thermostat base against the wall where you plan to mount it. (Be sure
the wires will feed through the wire opening in the base of the thermostat.)
6. Mark the placement of the mounting holes.
7. Move the base out of the way. Drill mounting holes. Use a hammer to tap in
the supplied anchors into the mounting holes.

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8. Fasten the base loosely to the wall as shown in Figure 1, using two mounting
screws. Place a level against the bottom of the base and adjust until level,
then tighten the screws. (Leveling is for appearance only, and will not affect
thermostat operation.)
9. Insert stripped, labeled wires into matching wire terminals. See “Wiring
Diagrams”, Figure 2.
CAUTION: Be sure exposed portions of wires do not touch other wires.
10. Tighten screws on terminal block. Gently tug on each wire to be sure of
proper connection. Double check that each wire is connected to the proper
terminal.
CAUTION: Installing batteries backwards can damage the thermostat.

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11. Install two fresh “AA” alkaline batteries in the battery compartment. Be sure
to match positive (+) ends of batteries with positive (+) battery terminals in the
battery compartment. (The thermostat will operate from 2 size “AA” alkaline
batteries or 24VAC power. When operated from 24VAC power, your thermostat will
maintain time and continuously display the temperature during a loss of AC power
with the batteries installed.)
12. Replace the cover on the thermostat by snapping it in place.
13. Turn on power to the system at the main service panel.
14. Test thermostat operation as described in the following section.
FAN OPTION SWITCH
Read the following information before setting the fan option switch (See figure 3). If you
are unsure of your application, contact a qualified service person.