Winterizing Fresh Water Tank/Water heater

[HerNibsOntario]

Ahoy fellow sailors! I have a Hunter 356 recently purchased and I'm completing my winterization. There seems to be two schools of thought on the fresh and hot water tank winterization. I'm up in Canada so we do see -40c on occasion..
1. Drain completely and any residual water won't be enough to crack the tank if it freezes. My tank seems to have about 1/2-3/4" residual after a thorough draining
2. Drain completely and add some RV Antifreeze
I hate the way RV antifreeze "taints' the tanks and repeated flushing doesn't seem to help much. I would like to hear from other members about what they do for their fresh water tanks and water heaters as well.

Thanks for your feedback!

 

[dlochner]

Water in the tanks is only an issue because the tank won't be dry and the humidity in the tank can help stuff grow in the warm fall and spring. The solution is pump out as much as possible, then use a wet/dry vac to get the rest out.

Keep AF out of the tanks. It is nigh unto impossible to get the stuff out in the spring, it just keeps diluting. Instead, some place on the suction side of the fresh water pump disconnect the hose and pump AF from that point forward through all the lines. The AF in the lines will flush out in spring.

Drain and by-pass the HW tank. There will be a little water in the bottom, no big deal there is lots of room for the ice to expand without doing any damage. There are by-pass kits you can install to make the job easier. Check an RV store or some boating goods stores. Camco makes one.

 

[shemandr]

On my former 356 I drained it. Then I disconnected the cold water feed so that when winterizing the non-tox didn't go into the hot water tank. I don't remember how I ended the cold water feed but it would have to be capped. I didn't like the non-tox smell in the hot water and since we didn't use large quantities of hot water it was hard to get rid of.

 

[MitchM]

NOOOOOO on the antifreeze. when it went to -17 degrees on lake erie , the guaranteed minus -50 water system anifreeze in my expensive isotherm pure stainless steel h w heater froze. it was a $700 mistake i will NEVER make again. now i drain , then suck out as much residual h 2 0 as i can .

 

[Peggie Hall HeadMistress]

I've posted complete instructions for winterizing fresh water and sanitation systems in the Plumbing and Sanitation forum. Y'all might consider moving the conversation there 'cuz there's also been a lot of conversation about the various aspects of winterizing both.

--Peggie

 

[sailme88]

 

[Davidasailor26]

I’ve done it both ways. On our old O’Day 28 we could tilt the water tank to ensure we got all the water out. Then we pumped air through the hot lines and AF through the cold water side. On our current Beneteau the heater is fixed in place and I’m less comfortable not knowing how much water stays at or below the outlet, so we let it fill with AF. In the spring I use the bleach purging regimen Peggie prescribes for commissioning tanks. By the time the bleach smell is out any residual AF is gone too.

 

[SailingLoto]

drain the tank, drain the heater. loop the inlet and outlet together. feed af to the pump and run through the system until pink from each spigot, hot and cold. If your hot water heater uses engine cooling water and your cooling system is open (not closed cooling) flush it with af as well.

I do this for a living, 6 days a week, 6 weeks every fall, 1000+ boats a season. Never lost one yet.

Do not put af in your tank. it will always smell.

 

[SailingLoto]

NOOOOOO on the antifreeze. when it went to -17 degrees on lake erie , the guaranteed minus -50 water system anifreeze in my expensive isotherm pure stainless steel h w heater froze. it was a $700 mistake i will NEVER make again. now i drain , then suck out as much residual h 2 0 as i can .

your af was diluted by the water in the hot water tank. always drain them.