Mars 70801 Installation And Operating Instructions Manual

[Page 1] Mars 70801

INSTALLATION AND OPERATING INSTRUCTIONS Non-Programmable Electronic Thermostat Heat/Cool ® Model 70801 70801-IM 12/14/06 3:06 PM Page 1 ...

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2 Compatible with low voltage single stage gas, oil or electric heating or cooling systems and single stage heat pumps. For use on 24VAC systems (not to exceed 30VAC) and 250mv to 750mv millivolt heating only systems. WARNING! • To prevent electri...

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3 Removing The Existing Thermostat 1) CAUTION: Make certain the power to the system has been disconnected. 2) Remove the cover of the old thermostat and locate the wires that are connected to the terminal board. IMPORTANT: Before removing these wi...

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4 • GAS / ELECTRIC: Configures the thermostat to either gas/oil or electric heating systems. • C / F: Sets the display in either Celsius or Fahrenheit. • NORM / HP: Configures the thermostat for normal heating/cooling systems or heat pump syste...

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5 5) Set the system switch to the OFF position. The system should shut down within several seconds. The LCD will again display only the room temperature. 6) Set the system switch to the COOL position and depress the blue arrow key until the tempe...

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6 Operating The New Thermostat 1) Set the System switch to either the HEAT or COOL position and the Fan switch to either the AUTO or ON position. NOTE: In AUTO, the system blower will run only when the A/C or heat is running. In ON, the system blo...

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7 Troubleshooting SYMPTOM CORRECTIVE ACTION Display is blank Check thermostat wiring & connections. Check circuit breaker/fuse panel. No heat Set system switch to HEAT and raise set point above room temperature. Check thermostat wiring and connec...

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8 Wiring Diagrams Typical 4-Wire System RC RH C G Y WBO FAN CONTROL HEAT CONTROL Install Jumper 24 VAC TRANSFORMER COOL CONTROL COM HOT 70801-IM 12/14/06 3:06 PM Page 8 ...

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9 Wiring Diagrams Typical 5-Wire System RC RH C G Y WBO FAN CONTROL HEAT CONTROL COOL CONTROL HEAT 24 VAC TRANSFORMER COM HOT COOL 24 VAC TRANSFORMER COM HOT 70801-IM 12/14/06 3:06 PM Page 9 ...

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10 Wiring Diagrams Typical 2-Wire Millivolt System RC RH C G Y WBO HEAT CONTROL 24 VAC TRANSFORMER COM HOT Typical Single Stage Heat Pump System RC RH C G Y WBO FAN CONTROL COMPRESSOR CONTROL REV. VALVE COOL ENERGIZED REV. VALVE HEAT ENERGIZED 24 ...

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11 Warranty ONE YEAR LIMITED WARRANTY Motors & Armatures Inc. warrants each new MARS thermostat against any defects due to non-conforming material or workmanship for a period of one year after the original date of purchase by a professional servi...

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INSTALLATION AND OPERATING INSTRUCTIONS Non-Programmable Electronic Thermostat Heat/Cool ® Model 70801 70801-IM 12/14/06 3:06 PM Page 12 ...