I'm not sure on your Essex, but on many Newmar coaches the valve is accessed via the utility bay. One must look at the bottom of the plastic bay tray and inward, past the plastic tray. Mine is on the left side of the bay, past where the plastic ends. It is a full arm's length and one must look hard to see the valve. A flashlight comes in handy to find the valve.
2005 Newmar KSDP 3910 + GMC ENVOY XUV 37K lbs Moving Down The Road
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