On the display
The panel shows UNIT WARNING: INVALID NUMBER OF COMPRESSORS SELECTED. The manual classifies it as a unit warning. It is displayed indefinitely: the warning appears after the VSD has been initialized and does not go away on its own — it clears only through the power-off and jumper procedure described below.
What it means
The warning reports an invalid number-of-compressors-select jumper configuration. When the VSD initializes, it reads the number-of-compressors-select jumpers in its wiring harness; if the configuration it finds is not valid, the warning is displayed indefinitely after the VSD has been initialized.
Why it appears
- No number-of-compressors-select jumpers are installed in the VSD wiring harness. In this case the manual notes that a “Number of Compressors Select” message is displayed.
- More than 1 jumper is installed.
What to check
- Turn OFF the control panel.
- Turn OFF the VSD control voltage.
- Go to the plug in the VSD wiring harness where the number-of-compressors-select jumpers sit.
- Check how many jumpers are installed: the configuration is invalid if no jumpers are installed, and equally invalid if more than 1 jumper is installed.
- Install the jumpers correctly in the VSD wiring harness. The manual notes that these jumpers are factory installed in the wire harness plug and should not require changes.
- Restore the control panel power and the VSD control voltage turned OFF in the first steps, and let the VSD initialize again.
Reset and restart
The manual does not clear this warning from the panel; it is cleared by de-energizing the unit and correcting the jumper configuration. To clear this warning, both the control panel and VSD control voltage must be turned OFF and the jumpers correctly installed in the VSD wiring harness.
The jumpers are factory installed in the wire harness plug and should not require changes, so on a unit whose harness plug is in its factory state the warning should not appear.
Questions engineers ask
What does UNIT WARNING: INVALID NUMBER OF COMPRESSORS SELECTED mean on a YORK YVAA?
It means the number-of-compressors-select jumper configuration in the VSD wiring harness is invalid: either no jumpers are installed or more than 1 jumper is installed. The warning is displayed indefinitely after the VSD has been initialized.
How do I clear the INVALID NUMBER OF COMPRESSORS SELECTED warning on a YVAA?
Turn OFF both the control panel and the VSD control voltage, then ensure the jumpers are correctly installed in the VSD wiring harness. After that, power the panel and VSD again.
Where are the number-of-compressors-select jumpers on a YVAA?
In the plug of the VSD wiring harness. They are factory installed there and, per the manual, should not require changes.
Do I need to replace or move the jumpers to fix this warning?
No changes should be needed — the jumpers are factory installed in the wire harness plug. The fix is to restore the correct configuration, since zero jumpers or more than 1 jumper both produce this warning.
Messages next to this one
The same message on other models
Source
Written from the manufacturer's manuals for the YORK YVAA; every number and designation on this page is checked against them before publication. The row of the manual this message comes from:
All YORK YVAA messages: fault codes · YORK YVAA documentation · YORK manuals