Rear deck drainage

I am loath to point this out in view of the shower pump switch thread in the other place.

The technical specs make no mention of DC operation so it would not be best practice to use one. The ones I used had a magnet to draw the DC arc away from the contacts. However sometimes the magnet fell out and they did not seem to suffer.

Anyway they are double pole switches (or used to be) so you either use connect pole and keep the other as a spare or connect to both poles so they each carry a proportion of the current.

I suspect they will be fine but can not give the OK to use one, but I would if I could nt find a DC one at a reasonable price.

That is the best way to do it if you are going to use an AC switch but then that's another complication and another set of potential failure points. It comes down to which is likely to be the more unreliable and I suspect in the case of these pressure switches there will not be much in it. I suspect on my boat I would go for "less complication".