Winterizing Fresh Water System

[robinsbd]

I am preparing to winterize my fresh water system for the first time.

My boat has an 8 gallon fresh water tank and 1 sink faucet.

Can you give me advice on winterizing this system? Also, the system has a through hull drain for the sink. Should I close the drain valve or leave it open for the winter on the through hull?

Thanks very much for the help.

 

[DeepBlue2010]

You do realize that when they say ?Winterizing fresh water system? they are not talking about the fresh water tank and the sink, right?!

While the fresh water tank has a winterizing procedure, very simple one really, the statement above usually refers to the engine itself.

Marine engines has few different configurations to keep them cool (cooling system configurations)

1. Fresh water system (a.k.a closed system) is one of them and the name is kind of misleading because what is really cooling the engine is antifreeze fluid not fresh water. Fresh water system by itself has two subcategories, it can be
   1. full closed or
   2. ? closed
2. Raw water cooling (a.k.a open system) in which you just suck sea water and circulate it inside your engine to keep it cool.

With that said, are you really asking about your fresh water tank winterization procedure or your engine?

 

[stonyloam]

Not sure how you are set up, first drain the tank. If you have a cartage filter, remove it and dump the water out. If you have an electric pump, remove the line and run it to pump it dry. Open the faucet and let it drain. Blow some air back through it to get all of the water out. I assume there is no trap on the drain, if there is either remove it and drain or dump in some RV antifreeze. I usually leave the valves open on my camper. Usually in a simple system like that the only things that would be damaged by a freeze would be the faucet or maybe the pump, as long as they are dry you should be OK.

 

[JoLin]

Not everyone has a compressor. OP has a very small tank and single faucet.

Robinsbd, do you have a water heater plumbed into the system? I suspect not, so here's the simple way to do it if you can't blow out the system with air..

1. Run the tank dry via the pump and faucets.
2. Dump 2 gallons of RV water system antifreeze into the tank.
3. Run the faucet until it runs pink, or you can run the tank dry. Either way, the pump and lines are now winterized. The pink stuff coming out of the faucet will winterize the drain as it leaves the boat. Leave the drain open or closed. Doesn't matter. You're done.

In the spring, run the tank dry again, put a couple of gallons of fresh water into the tank, run it dry and repeat that a few times to purge the AF from the system. Fill the tank with fresh water and add 1/4 cup of bleach to it. Run the faucet until you smell the bleach coming out. Shut it down and leave it for 24 hours. Run the tank dry again and refill it with fresh water. You're all set for the season.

My .02

 

[tpenfield]

I usually run all of the water out of the system, then I blow out the lines. I add a decent amount of AF to the tank and then pump through the system. I run the hot water side an extra amount to make sure I have purged any water from the water heater and am getting a pure AF out of the hot side of the faucet.

I would leave the thru-hull drain open.

 

[robinsbd]

Thanks to everyone for their suggestions. I ended up putting 3 gallons of AF into the fresh water tank and running the pump to disperse it through the sink lines and drain lines. It's a small 8 gallon tank.