VR-II / V-III Outdoor Units - Compressor Wire Insulation Short Circuit Risk
This article summarises Service Bulletin VRF-0151, issued 21 September 2017, covering a potential short circuit caused by compressor wiring rubbing against the edge of the control box / capacitor box.
- Applicable product: VR-II and V-III outdoor units
- Issue: Compressor wire insulation can be scraped by the edge of the control box.
- Possible result: Short circuit to the control box.
- Cause: Insufficient clearance between the bundled compressor / fan motor wiring and the capacitor box.
- Countermeasure 1: Protective tape added to the capacitor box.
- Countermeasure 2: Wire clamp position changed to increase clearance by approximately 20 mm.
Problem Description
The compressor wire covering may rub against the edge of the control box. If the insulation is damaged far enough, the conductor can short circuit against the metal control box.
Cause
A capacitor box containing the electrolytic capacitor is installed on the rear side of the control box. The original routing and bundling position of the compressor wires and fan motor wires provided insufficient clearance from this capacitor box.
Factory Countermeasures
1. Protective Tape Added
Protective tape was added to the capacitor box at the potential wire-contact points.
- Implementation timing: From June 2017 production
- The tape protects the wiring where it may otherwise contact a sharp or abrasive metal edge.
2. Wire Clamp Position Changed
The wire clamp position was changed to move the wire bundle further away from the capacitor box.
- The revised routing increases the clearance by approximately 20 mm.
- Implementation was introduced as a running production change after existing old-part stock was consumed.
Applicable VR-II Models and Serial Numbers
The following serial numbers indicate the production range incorporating the bulletin countermeasure.
| Model | Serial Number From |
|---|---|
| AJY144GALH | R001444~ |
| AJH144GALH | R001146~ |
| AJY126GALH | R001203~ |
| AJH126GALH | R001127~ |
| AJT126GALH | R001360~ |
| AJT108GALH | R001170~ |
| AOUA120TLBV | R000262~ |
| AOUA96TLBV | R000292~ |
| AOUA72TLBV | R000043~ |
Applicable V-III Models and Serial Numbers
| Model | Serial Number From |
|---|---|
| AJY162LALBH | R000540~ |
| AJH162LALBH | R000300~ |
| AJY144LALBH | R000628~ |
| AJH144LALBH | R000242~ |
| AJY126LALBH | R000562~ |
| AJH126LALBH | R000122~ |
| AJY108LALBH | R000574~ |
| AJH108LALBH | R000070~ |
| AJY162LATBH (AJZ162LALBH) | T000540~ |
| AJH162LATBH (AJZ162LALCH) | T000019~ |
| AJY144LATBH (AJZ144LALBH) | T000021~ |
| AJH144LATBH (AJZ144LALCH) | T000025~ |
| AJY126LATBH (AJZ126LALBH) | T000006~ |
| AJH126LATBH (AJZ126LALCH) | T000016~ |
| AJY108LATBH (AJZ108LALBH) | T000003~ |
| AJH108LATBH (AJZ108LALCH) | T000004~ |
| AJQ450LALBH | R001595~ |
| AJQ400LALBH | R001327~ |
Service Inspection Guidance
If inspecting an affected or earlier-production VR-II / V-III outdoor unit:
- Isolate electrical power and follow the applicable high-voltage safety procedure before accessing the control box.
- Inspect the compressor and fan motor wire bundle where it passes the rear of the control box / capacitor box.
- Look for rubbing marks, flattened insulation, cuts, exposed conductor or signs of arcing.
- Confirm protective tape is fitted at the potential contact area.
- Confirm the wire clamp holds the harness clear of the capacitor box.
- Where applicable, compare the clamp position with the revised arrangement providing approximately 20 mm additional clearance.
- If wire insulation is damaged, rectify the wiring and protective measures in accordance with the approved service procedure before restoring power.
