Winter head options

[thinwater]

I recently bought my first boat with a marine head. When I picked the boat up for the multi-day sail home, I took a portable head with me for the trip, since the installed head was winterized.

Is there a simple way to operate a marine head in the winter, when freezing is certainly a possibility? I would think live-aboards would have a solution, and although the boat would generally be heated, they would have to plan for the eventuallity that the heat would fail and the water would freeze. I searched the forum and the net and found nothing on the subject.

I would think that if you used the "dry bowl" valve position, left the inlet sea cock closed, and used a weak (+10F freeze perhaps - 25% glycol) antifreeze mixture poured from a jug all should be well.

(Near Annapolis, MD)

[Sandero]

Unless it get very very cold for a long time you won't freeze water in a boat that is heated or occupied.

If you consider that the water which the boat is in us usually well above freezing even when the temps dip below freezing of the air it is like having a "heat" source below the boat.

This is not to say that fresh water will not freeze in the plumbing system over the winder. It just takes a pretty sustained cold spell to get there.

Heads which have plastic construction might be more prone to cracking from frozen water. But if you pump it dry, you should be OK.

[thinwater]

One concern is that the whole bridge deck is not in contact with the water. The other is that the water is clearly little more than 32F and won't be for a long time. I had water bottles freeze hard in my other cat while in the water.

[sabray]

In shallow anchorages on the chesapeake bay you don't get the same kind of thermal exchange that you may get in deep New England harbors.
I lived aboard in new england and then on the chesapeake the boat is colder on the chesapeake then it was in new england. At least it seams that way.

[AnchorageGuy]

Never use any other antifreeze in your head than the pink marine stuff. It is usually pretty cheap. As liveaboard we are present if anything goes wrong with the heat. If you leave the boat for any period of time you need to close the seacocks, both intake and discharge, undo the hoses and be sure no water is in the hose or seacock. Stick the intake line in a jug of the antifreeze and pump it till it comes out the discharge. Any shortcuts and you get a hard freeze and you might have some repairs when it thaws out. we lived on the Chesapeake for a few years and as a service tech winterized hundreds of boats.