Resideo HZ432K/U TrueZONE® HZ432 Panel Kit

The HZ432K is a TrueZONE forced-air zone panel from Resideo (Honeywell Home) — 4 Zones, 3 Heat/2 Cool, supplied as a kit.

Zoning is what you do when one thermostat cannot describe the whole house. The panel takes a call from each zone thermostat, opens that zone’s dampers, closes the others and runs the equipment at the stage the call needs — so the finished attic and the north bedroom stop fighting each other through a single stat in the hallway.

Two numbers decide which panel. Zones is how many separately controlled areas it handles — this one is rated for 4 Zones. Stages is how much of the equipment it can drive: 3 Heat/2 Cool. A panel with enough zones but not enough stages will run a two-stage furnace as though it were single-stage, and the equipment loses the efficiency that was paid for.

It is also expandable to 32 with TAZ-4H panels — worth knowing before ruling this panel out on a larger job.

Heat pump compatible, with an emergency heat switch and automatic changeover. A zone panel that cannot handle a heat pump properly is the one that ends up running auxiliary strip heat when it should not.

Individual zone fan control lets one zone run its fan without calling the others — useful where a room needs circulation rather than heat.

It works with a discharge air temperature sensor, which is the part that protects the equipment when a single small zone calls: the panel watches supply temperature and backs the equipment down before the heat exchanger overheats or the coil freezes.

The kit version ships with what the panel needs to be commissioned rather than as a bare board: HZ432 Zone Control Panel, AT140 Transformer, C7735A Discharge Air Temperature Sensor. Buying the three separately costs more and leaves the transformer sizing to chance.

Count the dampers before sizing the transformer. Every actuator adds to the load, and the intermittent faults in a zoning system are usually a transformer running at its limit rather than the panel.

We stock these kit parts individually too: HZ432, AT140B1206, AT140B1214, C7735A1000.

• Brand: Resideo (Honeywell Home)
• Manufacturer Part #: HZ432K/U
• Type: TrueZONE forced-air zone panel kit
• Zones: 4 Zones (expandable to 32 with TAZ-4H panels)
• Stages: 3 Heat/2 Cool
• Voltage: 24 V
• Heat pump compatible: Yes
• Auto changeover: Yes
• Emergency heat switch: Yes
• Individual zone fan control: Yes
• Resettable fuse: Yes
• Includes: HZ432 Zone Control Panel, AT140 Transformer, C7735A Discharge Air Temperature Sensor
• UPC: 085267314374
• Category: Forced Air Zone Panels