Can you see where you water enters into your RV (from the inside.... Mine is under my bed where my fresh water tank is).
I can see the hoses come into the RV. One goes to the water tank (plus you will see a vent tube) and the other connects somewhere AFTER the water pump (But I never traced mine since it works fine). Look in that area.
I dont think you can "flush it out"....I bet you can unscrew it and clean it or replace it.
Let us know what you find.
2017 Axis / 25.4: Big Foot Levelers, Aims 1200 Watt inverter, Ceramic Window Tint, Full River AGM 6V batteries, Front Hellwig Sway bar / Rear Track Arm, Safe T Plus Steering Stabilizer, PD 4655 converter, Hard Wired Surge Guard, WEboost + WiFi Ranger, LED Headlights/Driving lights, TPMS, Surge tank, Tornado flush, Viair Compressor