YHJF60 - Low Heat / Low Cool

York Heat Pump: YHJF60

Re: Low Heat / Low Cool

The 5 Ton model of the YHJF heat pump uses a 2-stage scroll compressor and a Yorkguard VI control module.

It should also be matched with a Variable Speed air handler.

Since the 5 Ton model is the only unit in this series that uses a 2-stage compressor, it is very common to see one of the following issues:

• Wrong or Mis-Configured Thermostat
• Mis-wired Low-Voltage
• Wrong Air Handler

1. Wrong or Mis-Wired Thermostat

The YHJF60 requires a thermostat that is capable of controlling, and is configured for, a 3-Stage Heat / 2-Stage Cool Heat Pump. R, Y1, Y2, O, G, Aux, C

As of 4/20/17 the three thermostats we have that are capable of controlling this unit are:

• TH8320U VisionPro
• TH8320R or TH8321R VisionPro
• Prestige IAQ

2. Mis-Wired Low Voltage

If Y2 is not hooked-up at the Yorkguard module, the compressor will never operate at full capacity.

The following low-voltage wiring should be followed: