2017 Kenworth T680 - Sleeper A/C Not Blowing Cold - Cab is Fine

Question

I'm out on the road and the sleeper AC just quit. The front vents in the dash are ice cold, but the bunk just blows ambient temp air. The fan speed works fine in the back, just no cooling.

Since the front works, I know the compressor is spinning. I'm wondering if there is a separate expansion valve for the sleeper or if a blend door is stuck. It's getting hot back there and I can't sleep.

FleetMech_Ed · Answer

✅ Confirmed fix: Found the coolant shut-off valve for the sleeper heater core was stuck open. Even with the AC on, the heater core was so hot it was over-powering the evaporator. Replaced the electric actuator on the water valve and now it's freezing in the bunk.

PeterbiltPete · Answer

It's likely the sleeper expansion valve (TXV). They are notorious for sticking shut. If the front is cold but the rear isn't, and your pressures look okay on the manifold gauges, that valve is the 90% likely culprit.

2017 Kenworth T680 - Sleeper A/C Not Blowing Cold - Cab is Fine

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