Winterizing macerator in 2018 Winny Aspect 27k

[sueleibo]

We winterized our 27k yesterday for the first time but had a question at the end when we got to the macerator. I called Winnebago as I thought they skipped a step in the manual. The manual says to pour a cup of antifreeze down the drain in the toilet and the kitchen sink and then press and hold the waste pump switch for 5 to 10 seconds to get the antifreeze into the pump.

My question for Winnebago was why are they not telling us to open the gray valve to allow the antifreeze that has accumulated in the gray tank to be sucked up into the pump. The response was that you would need way more than one cup to make it from the gray tank through the macerator. He suggested removing the hose that comes off of the macerator leading to the dump hose and let any water in that hose drain out into the gray compartment and just sop up the water. We think that’s a poor answer.

So my question for the group is, what do you do to winterize your macerator pump?

We also tried opening up the macerator drain plug that is just off the gray tank at the 90 degree elbow which allowed any water in that tube to drain. Then we adding a garden hose adapter and tried to have the antifreeze suck into the pump by turning the pump on. That didn’t work. So we don’t know how critical it is to winterize the pump but we’re concerned that any water coming out of the pump going to the dump drain pipes will freeze.

[Robi.1014]

My macerator setup was home brew. Here's my opinion: The macerator itself does not have a check-valve, and the mounting angle (that I see in your photo) tells me you've done enough. There should be no water in the pump-head at all. And you having used the flush-out to drain water therein, there will not be enough water remaining to do any damage as it freezes.