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Accepts Optional IR Remote Control Accepts Comfort Call Phone Control Accessory Use with most Air Conditioning & Heating Systems including: 1 or 2 Stage Electric Cooling & 3 Stage Gas Heating, Heat Pump, Electric or Hydronic Heat. INSTALLATION INSTALLATION INSTRUCTIONS INSTRUCTIONS Venstar Inc. 08/07...
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(1) this device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation. Thermostat T1800 Tested to Comply with FCC Standards FOR HOME OR OFFICE USE...
Table of Contents Preparation Remove & Replace the Old Thermostat Configuring the MISC Outputs Wire Connections Wiring Diagrams Test Operation Calibrating the Thermostat Sensors TroubleShooting Page...
SECTION 1 Preparation Proper installation of the thermostat will be I2:00 accomplished by following these step by step AUTO instructions. If you are unsure about any of these steps, call a qualified technician for assistance. Assemble tools I2:00 AUTO Flat Blade Wire cutter Screwdriver &...
SECTION 2 Remove & Replace the Old Thermostat Remove the cover of the old thermostat. I2:00 AUTO If it does not come off easily check for screws. Loosen the screws holding the thermostat I2:00 AUTO base or subbase to the wall, and lift away. Disconnect the wires from the old thermostat.
SECTION 3 Configuring the MISC Outputs Section 3 Contents: Configuring the Jumpers..3.2 Explanation of Jumper Settings........3.3 Page 3.1...
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Configuring the Jumpers For additional flexibility, your thermostat has three configurable outputs. These outputs are designed to have different functions depending on how the jumpers are set (below). Each output, labeled MISC1, MISC2, and MISC3 may be set for one of the five choices available.
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Explanation of Jumper Settings W3 JUMPER SETTING If the jumper for MISC1, MISC2, or MISC3 is set to W3, the corresponding MISC screw terminal on the backplate will control a third stage of heat. W3 MULTI-STAGE OPERATION EXPLAINED - SECTION 13 of the Owner’s Manual The 3rd Stage of Heat is turned on when: (A) The 1st and 2nd stages have been on for the time required (steps #22...
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Explanation of Jumper Settings (continued) DEHUM JUMPER SETTING If the jumper for MISC1, MISC2, or MISC3 is set to DEHUM, the corresponding MISC screw terminal on the backplate will be connected to the dehumidification terminal of a furnace board. NOTE: Not all furnaces have a dehumidification terminal. DEHUMIDIFICATION OPERATION - SECTION 10 of the Owner’s Manual If your HVAC unit is equipped with a dehumidification system the thermostat will operate in one of two ways.
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Explanation of Jumper Settings (continued) Y2 JUMPER SETTING If the jumper for MISC1 is set to Y2 the MISC1 screw terminal on the backplate will control a second stage of cooling. Y2 OPERATION - SECTION 13 of the Owner’s Manual Control up to two Cool stages.
SECTION 4 Wire Connections If the terminal designations on your old thermostat I2:00 AUTO do not match those on the new thermostat, refer to the chart below, or the wiring diagrams that follow. Wire from the Install on the new thermostat old thermostat Function connector marked...
SECTION 6 Test Operation Turn the power on to the Heating/Air Conditioning I2:00 AUTO system. Press the MODE button repeatedly until the I2:00 AUTO HEAT icon appears on the display. Press Up or Down buttons until the set temperature is 10 degrees above room temperature.
SECTION 7 Calibrating the Thermostat Sensors Under normal circumstances it will not be necessary to adjust the calibration of the temperature and humidity sensors. If calibration is required, please contact a trained HVAC technician to correctly perform the following procedure. I2:00 Place the thermostat in the MODE...
SECTION 8 TroubleShooting SYMPTOM: The air conditioning does not attempt to I2:00 turn on. AUTO CAUSE: The compressor timer lockout may prevent the air conditioner from turning on, for a period of time. REMEDY: Consult the Owner's Manual in the Setup section to defeat the cycles per hour and compressor timeguard.
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TroubleShooting SYMPTOM: When controlling a residential heat pump, I2:00 AUTO and asking for cooling, the heat comes on. CAUSE: The thermostat reversing valve jumper is set for “b”. REMEDY: Set the reversing valve jumper for “O”. See pages 5.4 and 5.5. SYMPTOM: When calling for cooling, both the heat I2:00 AUTO...
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