YHJF24 - YHJF48 Heat Pump Wiring Diagram

THERMOSTAT: This application uses a Honeywell VisionPro Thermostat to control a 2-stage heat, 1-stage cool Heat Pump.

• It is possible to downgrade to a FocusPro or upgrade to a Prestige

SCHEDULE: The VisionPro thermostat is pre-configured as Programmable and has a default schedule with all temperatures set for 68 deg. Heat, 74 deg. Cool. However, the thermostat has the option to be Programmable or Non-Programmable.

To change the Schedule Options:

• From the Home Screen press "MENU"
• Scroll down to highlight and Select "Preferences"
• Scroll down to highlight and Select "Scheduling Options"
  • Select Programmable or Non-Programmable

WIRING: There are several important points to watch for on the wiring.

1. The "Y" wire from the thermostat must connect to "Y/Y2" at the air handler (not Y1), otherwise the indoor blower will operate on the Low Fan speed with compressor operation.
2. The Condensate Overflow Switch must be wired as-shown to break the "Y" signal to the outdoor unit.

FAN SPEEDS: Fan speed selection on the air handler is very important since we are using an oversized blower.

• The Red wire is the "Fan Only" and "Y1 Low Cool" speed. 
  • We default to motor terminal 3 (medium speed), but a lower speed can be selected.
• The white wire is the "Hi Cool/Heat" and "Aux Heat" speed.
  • It should be set no lower than motor terminal 2 (med-high speed). 
  • A higher speed may be necessary if heater limit trips become a problem.

HUMIDIFIER: The thermostat is pre-configured to control a Bypass Humidifier (if applicable).

• To control a humidifier from the thermostat a field jumper must be installed between "Rc" and "U1" at the thermostat.
• The humidity setpoint is accessed by selecting "Preferences" from the home screen, then "Humidity".
• If no humidifier is present, the Humidifier Mode should be set to "Off"