How a $15 Part Fixed an RV A/C Pulling 21+ Amps! (Dometic Dual Run Capacitor Diagnosis)

Is your RV air conditioner cutting on and off, or tripping the breaker? Don't replace the unit just yet! In this quick diagnostic breakdown, we tackle a Dometic RV HVAC system pulling 21.5 Amps—way above normal limits. After cleaning the coils made no difference, we killed the power, discharged the capacitors, and tested the dual run capacitor with a multimeter. What we found: Factory Spec: 20/10 µF (Microfarads) Fan (10 µF side): Completely dead Herm/Compressor (20 µF side): Reading 36 µF (drastically out of spec) After swapping in a fresh $15 capacitor, amp draw dropped back down to a healthy 14.75 Amps! 🧰 Tools Used: Multimeter with Capacitance (µF) reading capability (~$50–$70 at most local hardware stores) Replacement Dual Run Capacitor (~$15) Safety First: Always disconnect total power to the RV unit and safely discharge capacitors before testing electrical components.