Honeywell Heat/1Cool User Guide - Page 11

HEAT PUMP THERMOSTAT CROSS REFERENCE/SELECTION GUIDE Changing Fan Operation in Emergency Heat Mode for Electronic Thermostats In the emergency heat mode (system switch in EM. HT. position), the thermostat controls the fan operation with a call for first stage heat. This means that when the thermostat calls for heat, the thermostat also calls for fan operation. However, this fan operation is not desirable on some types of systems. To change the fan operation on the TRADELINE and SUPER TRADELINE models, follow the wiring diagram shown below. Connecting the thermostat and relay to the equipment in this manner disables the fan switch in the emergency heat mode. During normal operation, the fan switch is enabled and the fan operation is as described in the installation instructions. R (Power) E C (Common) E (EM. Heat) G G (Fan) Thermostat R8222B Relay Equipment M13232 Fig. 4 Changing fan operation in emergency heat mode for electronic thermostats. Heat Pump Manufacturer Relay Wiring Connections The wiring connections for some thermostats to specific types of heat pump equipment require a separate relay for proper operation. Refer to Fig. 5 through 13 for the wiring connections of these types of equipment. Existing Control Equipment Function Terminal Designation Transformer Common C 1st Stage Cooling Y1 1st Stage Heating W1 New Terminal Designation C Y O M13235 Fig. 5. Relay wiring connections for Carrier equipment (typical 38BQ), and T8511M, T8611M, PC8900/W8900B1002. Require relay (R8222B1067 typically) for proper operation. 70-6627 • 9