Description
HVAC evaporator core for Peterbilt and Kenworth heavy-duty truck cab air-conditioning systems. Replaces Paccar W2078001, the parallel-flow aluminum core that mounts inside the dash HVAC box and absorbs cabin heat as R-134a refrigerant evaporates across its tubes — the failure point that produces warm-air-only AC and refrigerant-system leaks under the dash.
Signs You Need a New Evaporator Core
- AC system loses charge repeatedly with no visible leak at the compressor, condenser, or hose fittings
- Cool air at startup that fades to ambient air after a few minutes of operation
- Wet floor on the passenger side from the evaporator drain backing up or the core cracking
- Sweet or chemical smell from the dash vents (refrigerant or oil from a leaking core)
Specifications
| Part Type | HVAC Evaporator Core |
|---|---|
| Refrigerant | R-134a |
| Application | Peterbilt & Kenworth in-dash HVAC box |
Cross References
This evaporator core replaces or is equivalent to the following part numbers:
- Paccar / Kenworth: W2078001
- Paccar / Peterbilt: W2078001
Applications
This evaporator core fits Peterbilt and Kenworth Class 8 cab HVAC systems that originally shipped with Paccar W2078001. Verify the existing core dimensions and inlet/outlet line orientation against your dash before ordering — Paccar revised the in-dash HVAC box configuration across model years.
Evaporator replacement requires evacuating and recharging the AC system; this part should be installed by a technician with proper AC service equipment.
