(07-07-2026 )JimT Wrote:  I don't know about that model or where you operate, but I usually replace my air dryer cartridge every 6 months or so.

Where is the dryer unit located and is it connected to the compressor via a braided hose? If I remember correctly the braided hose is supposed to help cool the compressed air, condensing some of the moisture before it hits the dryer. Even with a dryer you'll still get some moisture in the first (wet) tank. It's possible even after draining that some water remains. Perhaps the drain valve is getting blocked by debris (happens to my shop compressor tank all the time) or maybe the drain isn't the lowest point on the tank preventing full drainage (the tanks on my peterbilt lay horizontal but drain from the ends which sit about half to an inch above the lowest point in the tank)?

I'm not an expert here, but what comes to my mind is that you have an air leak. Some thoughts:

* Disconnect the braided hose at the compressor and see what comes out.
* Check the control tube between the governor and the compressor for pressure, leaks or blockage.
* Pressure test all the hoses and tubing for leaks. (I like to use ptc fittings with a plug on the threaded side along with a digital tire inflator gauge with ptc fitting instead of a tire chuck. Connect to desired tubing, pressurize through inflator and watch gauge for pressure loss). You can't always hear a leak, but the gauge won't lie.
* My governor is located on the bottom on my air dryer. Sometimes after it purges it doesn't seal fully allowing system pressure to drop.
* You didn't mention what your system air pressure was doing. Your air leak might be further down the line causing total air pressure to drop low enough to kick the compressor back on, especially if 2-3 minutes pass between purging (governor cut-off). Cab or suspension air bags are common culprits that you don't always hear.

Excess water in the air tank could reduce tank air capacity, but wouldn't otherwise directly cause the compressor to kick back in.