Winterizing the Water System

[Vancouver_SDA]

Hi,

I have a Sundancer 240 and plan to keep her moored over the winter. I hope to use her about once a week (depending on the weather). The temperatures here over the winter does not usually drop below -5C (23F) and the seawater does not freeze.

I plan to put RV antifreeze through the water lines, but have a questions about the heater. Should I "bypass" the heater and not put any antifreeze in? If I do put antifreeze in the heater what should I do, if anything, about the heat exchanger. Can antifreeze be safely heater through a heat exchangers? Any info would be appreciated.

Thanks.

 

[Lazy Daze]

I assume you have checked with locals and that they don't winterize their engines? If you haven't, I wouldn't "just do it" - I would check around, first.

For the HWT, I think it would be safest to drain it (no need to put AF in it), then disconnect the lines coming from the engine. Since the heat exchanger inside the HWT is much smaller than your engine, it's also more likely to freeze. Flush the heat exchanger with AF till a nice pink color comes out.

You could simply connect the two rubber hoses (that come off the engine) together... or, even better, remove one hose and install the free end of the other hose onto the open barb fitting. But I think it would be best to remove the pipe-to-barb fittings (typically just behind the t-stat housing/starboard side and the other is on the circ pump) on the engine side and screw in plugs (don't quote me, but I think they are 1/2" pipe fittings and a standard garboard drain plug would work).

 

[Alex F]

To be on the safe side I would winterize the HWH and take off the heat exchanger hoses connecting them together to bypass the HWH. This way there's no raw water going thru the HWH.

I never had my boat in during winter months, but one most important item to consider is the constant 110v to keep the batteries charged. I'd also add a ER heater as you can never depend on the weather and the last thing you want is for something to freeze.

 

[sbw1]

To be on the safe side I would winterize the HWH.........

No need to do this. As was advised above, just drain it and make sure the exchanger has antifreeze in it. Any small amount of water in the actual tank will freeze, and since it has plenty of room to expand, nothing breaks. Antifreeze in the water heater tank is kind of a pain to get rid of in the spring time.