Addition of ACC0410 Add-A-Wire to Venstar Thermostats

Addition of ACC0410 Add-A-Wire to Venstar Thermostats

The ACC0410 Add-A-Wire is an accessory used when an extra wire needs to be added to the Venstar thermostats, when adding heating or cooling to a heat-only or cool-only system or when fixing a broken wire. It can also be used when adding cooling to a heat-only system.



Sample Wiring Diagrams

For thermostats that need 5 wires, the accessory is used with the existing 4 wires. This is where no extra wires can be run.

Systems that have heating with 3-wires can also use the accessory to introduce cooling.

Where heating and cooling is needed, It can be used with 2 existing wires. In this setup there is no independent fan switching.


In the sample diagram below, the 4 existing wires can be used to accommodate a single stage heat pump.

In some cases, you may need to sacrifice the independent indoor unit fan control. Follow the steps below:
  1. Connect the wire from the G terminal (which controls your indoor fan) to the C terminal (common) on the thermostat.
  2. Move the G terminal (controls indoor fan) wire to the C terminal.
  3. Connect a jumper wire from the Y terminal to the G equipment terminal at the heating and cooling equipment. This way, when the thermostat calls for heating or cooling the fan will turn on without the option of independent fan control.
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