Hot Water Tank Winterization

JonnyM

This is my first boat with an Atwood hot water heater that routes through the engine.  I have a bypass kit for the hot lines out of the heater to my faucets on order.  My question is what size radiator hose do I need to make the bypass for the engine lines?

Thanks in advance!

jhofmann

Why bypass the water heater engine lines? I run anti-freeze through the engine which includes the hot water heater, using a set of muffs, and a modified 5 gallon bucket full of antifreeze.

seguir

My understanding the bypass of the water heater engine lines is really only necessary if you are removing the hoses off the housing and manually poring the antifreeze thorough the hoses.   I believe the hose is a 5/8 inner.  My question is how many gallons are necessary when using the muffs if you drain the engine before running the antifreeze thorough?

Dream_Inn

Well, for raw water I usually run 5 gallons of pink thru it.  Closed loop, fresh water, I use 2-3 gallons.  For those, the engine antifreeze is in the block and the hoses to the water heater, so no concern there.

onislandtime

Agree with @Dream_Inn. I use a hose to loop the hot and cold, then drain the water heater. I have closed cooling system.
Check this link for winterization. Great tips from Fritz
https://www.youtube.com/watch?v=N-pKC9JzuOw

Here is another one that has several winterization DIY on the channel
https://www.youtube.com/watch?v=rc69rxFM_d4

Trashman

Love eddie!   His videos are really good.  

MDboater

The hoses from the radiator contain antifreeze so there is no need to do anything with them.  Here is the process I used for winterizing the water systems (substituting what I would have done if I had a bypass valve).

1) Drain the fresh water tank using 1 or 2 faucets until about an inch of water remains.  Try not to run the galley pump dry.  Unhook the strap securing the fresh water tank.  

2) Prop up the aft end of the tank (I used a piece of 2x4) so that water collects near the tank outlet.  Empty the tank the rest of the way using the cockpit faucet.  You will notice that some residual water remains in the tank. Try not to run the galley pump dry.

3) Bypass the hot water heater using the bypass valves.

4) Open the drain valve on the hot water heater and drain the tank.  Opening the pressure relief valve will remove the vacuum in the tank and enable faster draining. Close the drain and relief valves on the hot water tank.

5) Put 1/2 (one half) gallon of pink antifreeze in the fresh water tank. Empty the tank the rest of the way using the cockpit faucet.  This step addresses the residual water from step 2.  You will still have residual water in the tank but now it is partly antifreeze.  The point is that you want to prevent that residual water from diluting your antifreeze too much.  Try not to run the galley pump dry.

6) Repeat step 5.

7) Put 2 gallons of antifreeze in the fresh water tank.  

8) Cockpit faucet: Open the faucet and run water for about 15-30 seconds.  The water will already be pink from steps 5 and 6 but you want to have a high concentration antifreeze flow through the line.  Close the faucet.

9) Transom shower faucet: Open the cold valve and run water until you get a steady flow of pink.  Close the valve.  Repeat for the hot valve.

10) Repeat step 9 for the galley faucet and the bathroom faucet.  

11) Add additional antifreeze to the fresh water tank if needed.

12) Open bathroom faucet hot and cold valves to empty antifreeze from the fresh water tank as much as possible.  Try not to run the galley pump dry.

13)  Remove whatever was used to prop up the fresh water tank in step 2 so the tank now lays flat.  Leave the tank strap disconnected and whatever you used to prop the tank next to the tank because you will use it in the spring when you flush the antifreeze from the fresh water system.  

14) Turn off the galley pump.  Open each faucet valve to remove pressure from the lines.  Close each faucet valve.

15) Unscrew the base of the fresh water strainer.  Empty the antifreeze. Clean the strainer and reinstall.  

I didn't have a bypass valve so I consumed significantly more antifreeze through the hot water heater while winterizing.  I don't know for certain if opening the valve on the hot water heater removes all residual water such that you don't need to flush any antifreeze through the hot water heater.  I think opening the valve and draining is sufficient but perhaps someone can confirm.

There are 2 versions of pink antifreeze at West Marine.  A cheap version that is a blend of alcohol and propylene glycol and a more expensive version this is only propylene glycol.  It is claimed that the alcohol deteriorates valve seals.  As such, I recommend the more expensive, all propylene glycol, version. 

VERY IMPORTANT FOR NEXT SPRING (Summerization):  When you get ready to use the boat next spring, make sure that your hot water heater is filled with water before you turn it on.  Otherwise, the electric element will likely burn out.   After flushing the antifreeze from the the hot and cold water lines, fill your fresh water tank and adjust the bypass valves so you have flow through the hot water heater and flush the hot water lines some more.  This should ensure a full hot water tank.  

Good luck!!

. 

Dream_Inn

Nice details MD!  I do a little different and not put any pink in my fresh water tank and I do actually run tank dry with pump.  Then I use an air compressor on the city water connection and blow it all out of every hose.  Then I remove hose from tank and put into gallon of pink and let the pump draw it thru each sink and shower.

I do use a heater bypass and just open the drain valve and the pressure relief valve all before starting the process.  I don't put any pink in there.  The above does apply to hot water lines as well.

JonnyM

Thanks guys, I really appreciate the help.  Going down today to work on things.