[kg5ie]

I am attempting to replace a Lennox model 51m33 with a Honeywell TH8320U1008 7day 3/h 2/c Vision PRO 8000 Touchscreen Programmable Thermostat on a heat pump.

The heat pump has one heat, one cool, emergency strip heat.

The Lennox 51m33 was wired as follows:
Orange - Reversing Valve - cool
Red - 24v ac
Green - Fan
Yellow - Y1 First Stage Cooling
White - W1 Aux Heat
Black - 24v Common


I have wired the Honeywell sub - base using the markings for heat pump as follows:

Page 5 of install manual 2h/1c heatpump with aux heat)

White - emergency heat relay
Red - Power jumped to RC (left jumper on)
Orange - o/b changeover valve
Yellow - Compressor relay
Green - fan relay
Black - 24v common

In the setup I have set the following:

170 System Type - 7 (2 heat / 1 cool heat pump (with aux. heat))
0190 Changeover Valve - 0 o/b terminal controls valve in cooling


I left the other settings at factory default.

The unit just does not seem to be operating normally. In the heat mode, the compressor unit is icing up. It never seems to go to a defrost cycle.

Is my wiring correct? Have I missed something critical in the setup?

Thanks in advance.

Bill