TrueZONE Wiring Visualizer

Interactive diagnostic tool for troubleshooting condenser issues in TrueZONE zone control systems. Walk through a step-by-step decision tree to isolate why a condenser won't shut off.

For Licensed & Trained HVAC Technicians Only

This checklist is intended exclusively for use by licensed, certified, and trained HVAC professionals. It is not a DIY guide and should not be used by untrained individuals to perform repairs or diagnostics. The purpose of this checklist is to help qualified technicians maintain a consistent, step-by-step workflow so that no critical step is overlooked or skipped during service.

Thermostat Z1Thermostat Z2Thermostat Z3TrueZONE PanelRGYWCRGYWCRGYWCRGYWCRGYWCRGYWC
R — 24V PowerG — FanY — CoolingW — HeatingC — CommonRh — Alt PowerDamper Motor

Condenser Diagnostic

Interactive troubleshooting guide for when the condenser won't shut off.

Kill 240V at disconnect before touching contactor
stepStep 1 of 4

Condenser running, all stats off

All thermostats are satisfied or off, but the outdoor condenser unit continues to run. Follow this diagnostic to isolate the cause.

Field Notes

Before starting: confirm all thermostats are truly off or set well above room temp. Check for any zone board test modes that may be active.
decisionStep 2 of 4

Check Y wire at equipment terminals

Meter Y to C at the equipment output terminals on the TrueZONE panel or furnace control board.

decisionStep 3 of 4

Disconnect Y at furnace control board

24V is present on Y. Pull the Y wire off the furnace control board terminal to see if the signal is coming from the board or upstream.

decisionStep 4 of 4

Isolate at TrueZONE panel

The signal is coming from upstream of the furnace board. Pull the Y wire off each zone input on the TrueZONE panel one at a time. Whichever zone disconnect kills the signal is the culprit.

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