I got rid of that cheap little check valve years ago and added a fitting with a manual shut-off. In fact, my water inlet has: shut-off fitting; pressure gauge; quick disconnect.
Only drawback is if the park water pressure fails I need to go out and manually shut the valve before turning on the pump. Otherwise works great and no more leakage when not connected.
'99 Volvo VNL610 - 425 HP Volvo; Super 10 Spd
'13 smart CityFlame on Volvo
'05 Newmar Mountain Aire 35 BLKS
Trailer Saver; Bigfoot; Pressure-Pro.
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