john deere air compressor for planter Air Conditioning Conversion Kit for John Deere 4040, 4230, 4240, 4430 - A6 to Sanden, 990-404K

john deere air compressor for planter Air Conditioning Conversion Kit for John Deere 4040, 4230, 4240, 4430 - A6 to Sanden, 990-404KReplace your aging A6 compressor with a modern Sanden style A C system using this complete conversion kit from AP Air. The 990 404K covers one of the broadest fitment ranges in the John Deere lineup spanning both classic row crop tractors and large combines and includes everything needed for a clean, reliable installation. What's Included (SKU: QFS 990 404K) Sanden Style Conversion Kit replaces the original A6 piston compressor with a lightweight,

Replace your aging A6 compressor with a modern Sanden-style A/C system using this complete conversion kit from AP Air. The 990-404K covers one of the broadest fitment ranges in the John Deere lineup — spanning both classic row-crop tractors and large combines — and includes everything needed for a clean, reliable installation.

What's Included (SKU: QFS-990-404K)

• Sanden-Style Conversion Kit — replaces the original A6 piston compressor with a lightweight, efficient rotary unit
• Receiver Drier — new desiccant to keep moisture out of the system
• Expansion Valve — controls refrigerant flow for optimal cooling performance
• O-Ring Kit — all seals needed for a leak-free, R134a-compatible installation

Designed to use your original belt and hoses — no custom fabrication or hose rerouting required.

Compatible John Deere Models

Combines:

• John Deere 6620
• John Deere 7720

Tractors:

• John Deere 4040 & 4040 Euro
• John Deere 4230
• John Deere 4240, 4240 Euro & 4240S
• John Deere 4350
• John Deere 4430
• John Deere 4440 & 4440 Euro
• John Deere 4630
• John Deere 8430 4WD
• John Deere 8440
• John Deere 8630
• John Deere 8640

Why Upgrade from the A6 Compressor?

The original A6 piston compressor is heavy, inefficient, and increasingly difficult to find parts for. The Sanden-style rotary compressor offers:

• Less engine load — lighter weight means less parasitic drag
• Better cooling efficiency — especially at low RPMs during field work
• R134a compatibility — works with the modern, readily available refrigerant standard
• Widely serviceable — any shop with modern A/C equipment can service a Sanden-style system

Installation Notes

• Flush the system before installing to remove residual mineral oil from the old A6 system
• Use PAG oil specified for the Sanden compressor — do not mix with old mineral oil
• Replace all O-rings with HNBR (green) O-rings rated for R134a (included in kit)
• Have the system professionally evacuated and recharged with R134a refrigerant