Description
Built for Class 8 A/C service, the 2601394 thermostatic switch ships ready to install. This 12/24V adjustable-temperature switch is designed for heavy-duty truck and equipment A/C systems requiring operator temperature control. The 48-inch capillary tube provides extended sensor reach, allowing flexible evaporator placement. Operator turns the knob to set desired cycling temperature between 26°F and 52°F.
Signs You Need a New Thermostatic Switch
- A/C compressor clutch cycles erratically or fails to engage
- Evaporator coil freezes up regardless of switch position
- Air conditioning does not respond to temperature adjustments
- A/C runs continuously and cannot be modulated via knob control
Specifications
| Manufacturer | Red Dot |
|---|---|
| Part Number | RD4125-48 |
| Part Type | Rotary Variable Thermostatic Switch |
| Voltage | 12/24V (bi-voltage) |
| Capillary Tube Length | 48 inches |
| Adjustable Temperature Range | 26°F to 52°F |
| Cut-in/Cut-out Cycle | Cuts in 34°F, cuts out 26°F (at nominal setting) |
| Refrigerant Type | R12/R134a |
| Control Type | Knob (manual) |
Cross References
This part replaces or is equivalent to the following part numbers:
- Red Dot OEM: RD4125-48, RD-5-4125-48, BD1035
- Also known as: MVA1-4185, 9533N399, A45-1094
Applications
This rotary thermostatic switch fits:
- Freightliner FLT, FLC, FL Series (all with rotary knob control)
- International, Mack, Peterbilt heavy-duty trucks
- Refrigerated transport vehicles requiring adjustable A/C control
- Agricultural and industrial equipment with 48-inch capillary routing
Verify capillary tube routing distance and electrical voltage before ordering to confirm fitment.
