Greywater dump pauseing

[ComputerChips]

I have a '16 Ace. When I dump I usually let the backwater go first. That seems to go in one continuous flow until empty. Then I close that valve and let the Greywater go 2nd to help rinse the hose out, but the Greywater seems to flow for a while and the gurgle like it's in a airlock situation and will then drain some more before finishing. Shouldn't the Greywater tank be vented so that there would be no hesitation when draining it?

[Tess'Human]

Sounds like you may have a blockage in the vent to atmosphere (if your coach has such a vet pipe through the roof) or if not then a malfunctioning "Air Admittance Valve" which may be located (if more than one) under the sinks, or behind the washer dryer.

[Travelin' Texans]

Mine does the same & I suspect they got the vent that goes through the roof shoved too far into the grey tank so it drains slowly til it gets below the vent pipe.