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<h2 id="isPasted"><u>Introduction</u></h2><p>The &quot;P9&quot; error code indicates a DC fan malfunction. This article is for <a href="https://www.pioneerminisplit.com/collections/vertex-ducted-central-split" target="_blank" rel="noopener noreferrer">Vertex Ducted Central Split (DYC-18) systems</a>.&#xA0;</p><p><strong>Cause:&#xA0;</strong>The fan drive module is experiencing abnormal detection. D</p><h2 id="troubleshooting-diagram"><u>Troubleshooting Diagram<img src="https://attachments.gorgias.help/Q9r0k7BYaV2vg13y/hc/9JWjXVxG8m6DvMqm/2026020315-33832da2-09c2-4dca-9e91-6cbcf891e64d-dyc18_troubleshooting_p9.png" style="width: 800px;" class="fr-fic fr-dib fr-bordered"></u></h2><h2 id="troubleshooting-notes"><u>Troubleshooting Notes</u></h2><ul><li>Check if the power supply is normal, which is a phase voltage of 208-230V. Confirm that the power supply is properly functioning.&#xA0;<img src="https://attachments.gorgias.help/Q9r0k7BYaV2vg13y/hc/9JWjXVxG8m6DvMqm/2026020315-c9934a0f-337c-4aed-ae7a-33638e2d3047-dyc18_troubleshooting_f9_multimeter.png" style="width: 300px;" class="fr-fic fr-dib fr-bordered"></li><li>Check if the output voltage of the motor port on the mainboard is 310VDC.&#xA0;<img src="https://attachments.gorgias.help/Q9r0k7BYaV2vg13y/hc/9JWjXVxG8m6DvMqm/2026020315-1c5a1948-acb1-4163-b550-4a652edb2e19-dyc18_troubleshooting_p9_motor_port.png" style="width: 300px;" class="fr-fic fr-dib fr-bordered"></li></ul>

The "P9" error code indicates a DC fan malfunction. This article is for Vertex Ducted Central Split (DYC-18) systems.

P9 Error Code

Troubleshooting

By Error Code

Error Codes for Vertex Ducted Central Split (DYC-18) Systems

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CL error code

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P9 Error CodeUpdated 4 days ago

Introduction

Troubleshooting Diagram

Troubleshooting Notes