Super C Aux Air Compressor for Seats

[KenK]

I have a 2026 Newmar SuperStar 4159. The aux air compressor is located on the pass side first storage compartment. This compressor is use for operating the seats when the chassis air is not available.
Issue: The compressor will not turn off. Must use the switch in the storage compartment to shut off the compressor. If run continuously, can overheat and fail, or worse.

I tried letting the compressor run for 5 minutes. Thinking it would charge the small tank and shut off.
I tried starting the engine and letting the chassis air charge to 120psi. The Aux compressor kept running.
I can hear no leaks. Hard to trace air lines to the seats.
Chassis air does not show any signs of leaks with engine off.
Seats work fine using chassis air.
I have not taken apart the box the aux compressor is mounted in. There is no access door to the compressor.

Does anyone have any info (electrical drawings, installation drawings, manufacture name, etc) for the compressor and how it is integrated with the seats.
How does the aux comp and the chassis comp both feed air to the seats? These systems have to be cross connected somewhere.

Pressure sensor could be bad? Air line may be disconnected?

Thanks in advance for your input.

 

[KenK]

There is no info provided in the owners manual regarding the aux air compressor.
All I could find on Newgle was that there is a switch to turn off the compressor. And that there is a shut off valve in case of an air leak. NOTE: The shut off valve is not installed in my system, but is shown in the Hadley install manual.

So I started system troubleshooting. Ref the attached pics and the install manual.

This is a Hadley 850 compressor system. Parts list provided in the attached manual.
The large white wire iin the picture is chassis ground.
The large blue wire is chassis +12VDC power, which connects to the On/Off switch.
Orange wire goes from the On/Off Switch to the Pressure Switch (110psi/135psi) then to the the pump motor.
The large plastic gray part is a check valve, preventing the Aux Air Comp from back feeding into the chassis air system.

My pressure switch is faulty. Will not open on high pressure (135psi). Note the pressure gauge reading of 200psi and the compressor still runs. (The good news - 200psi plus and holding means no leaks)
Also found the compressor end cap had vibrated out of the pump, or was blown out by excess pressure, exposing the shaft and piston rod. Not good.

I should be able to tap the cap back into position using some red locktite. It's not something that should ever come out.
I'll contact Newmar about warranty coverage for the pressure switch. Approx $50-$65 item plus shipping.

Hope this info helps anyone else that may have questions regarding the Auxiliary Air Compressor.

 

[KenK]

Thinking more about this....
There is high possibility that the compressor has sustained damage.
- Cycle time is 7 minutes on 30 minutes off - This ran for a least a couple hours if not more. I was driving and did not hear the compressor running until after I shut the engine off.
- unknown damage to due to heat in cylinder , excessive pressure, excessive heat in motor windings.

I'll press Newmar for a new compressor and pressure switch to be covered under warranty.