Water line pressure test

[Campnjoe]

So I winterized the coach via the air method and I noticed that the lines would slowly bleed down from 30psi. Shouldn't they hold the pressure? Doesn't this mean there is a leak somewhere? It didn't drop right away, or quickly, but it was dropping pressure around a psi every few minutes.

[Porkchop]

Air pressure will leak down a lot faster than water pressure

[16ACE27]

might be back-leaking through the water pump to the FW tank.