What about bypassing water heater?

2

240da

New Member
Jan 7, 2009
105
Atlanta, GA/Lake Martin, AL
Boat Info
2006 240 Sundancer
Engines
350 MAG Horizon w/Bravo III 20p SS props
Since someone asked me to start this thread in the "generator" thread; here goes.

First, what are we talking about when we say "bypassing the water heater"? I assume you mean installing a bypass hose so you can winterize without having to fill the heater with propylene glycol. For the record, mine has the hose installed.

Seems very straightforward; what are the issues -- if there are any?:smt001
 
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Ok, after reading forever about genny's on boats, I know that this thread might also get interesting; but I also would like to know about this subject.

My boat came with the ability to by-pass the HWH for the purposes of winterization; which is exactly what I did a couple of months ago. Now I'm getting concerned that this isn't a good thing to do. Can someone shead some light on the issue.

And please, go easy as I'm new to all these issues.
 
Bypassing the water tank means you do not have to winterize it with the special pink water system antifreeze's.

You open the valves to the tank bypass, in effect closing any source of water to the water heater and then drain the hot water tank, no water in the tank,nothing to possibly freeze and bust.
 
Exactly! I've done this for years with no issues. If someone has a reason not to use this method I'd like to hear it.
 
Pseudomind said:
Bypassing the water tank means you do not have to winterize it with the special pink water system antifreeze's.

You open the valves to the tank bypass, in effect closing any source of water to the water heater and then drain the hot water tank, no water in the tank,nothing to possibly freeze and bust.
Click to expand...

This is correct - however make sure you can truly drain all of the water out. I don't winterize my boat but used to winterize my travel trailer so I'll give you my experience there. I would drain all of the water out of the hot water tank and then add some antifreeze - maybe 1/2 gallon - prior to using the bypass valve. It's easy to flush out in the spring and gives a bit of peace of mind. Up to you on how much water you think is left after draining and if this is warranted or not. The good news is the bypass allows you to not fill it full of 6 or 10 or more gallons of antifreeze when it's not needed.
 
240da said:
Since someone asked me to start this thread in the "generator" thread; here goes.

First, what are we talking about when we say "bypassing the water heater"? I assume you mean installing a bypass hose so you can winterize without having to fill the heater with propylene glycol. For the record, mine has the hose installed.

Seems very straightforward; what are the issues -- if there are any?:smt001
Click to expand...

I also said at the end of the post "Never mind".... It's a long story, goes back several months.
 
I bypass the HWH and drain whatever I can out through the little drain valve at the bottom. The tank is cylindrical so even if there's a few ounces at the bottom (even a gallon) it can expand up the sides and nothing bursts.
 
When I was in the keys a month ago i had a mechanic come out and pressure test my engine cooling system for a leak. while under the hatch he saw my water heater and told me I should disconnect it and remove it, i asked why. He said that the water heater is one of the most common reasons boats sink while underway. Mine cycles warm coolant through it to heat water while underway & he said they commonly start to leak and then fill the bilge with raw water while underway. boat starts running slower, owner throttles up, boat sinks even faster....

the heater is still in the boat, I think his opinion was stupid, but since we are on the topic...
 
I suppose that could happen; but what makes that scenario different than any other ruptured hose?

Anyway, ours is closed cooled so the heated coolant going to the water heater heat exchanger is part of the closed system -- meaning you would only loose a gallon or two before engine would overheat.
 
There used to be some posts by folks who thought the way to winterize the hot water loop of the potable water system was to fill the heater with pink and run that through the faucets on the boat. While this works, it takes a lot of antifreeze to get the protection and it stays too long in the spring and is hard to flush out. You end up with smelly water and makes for bad showers. The bypass prevents that. You should not pour pink in your fresh water tank for the same reason. It's hard to flush out, makes your water and ice taste bad. Still for some people, old habits die hard.
 
Eric
If your HWH also works on shore power, you can just disconnect the engine water part. Or you could replace it with an electric one. But I agree with our assessment of the mechanic's instruction - uninstalling the unit to prevent sinking??? That's a bit excessive.
 
I have not had any issues keeping my hwh connected. I like having hot water while on a mooring by just starting the engine, since I have no genny.

I have the quick disconnect fittings so I just connect the in-feed cold water line to a spare in-line connector then connect to the exiting hot water line to bypass the heater for the winter. And, as others have mentioned, I drain and blow out the water in the heater to winterize. I also use the pink stuff in the fresh water tank, but flush it out and use a bleach mixture in the spring to cleanse the system. I am pretty sure I got those details here or on SRO. It has worked well for me for five years.
 
Dude....I almost had my boat 'sink' because of a leaking water heater. It's also a 270! I noticed a little bit of water in the bilge and finally traced it (after wiping up several times) from the water heater. I just by-passed the water heater with the existing hoses. Don't plug off the engine....the water circulates and you don't want to change the circulation pattern. I'm considering taking out the water heater > we've never used it and likely don't plan to, however, I'm sure this would change the ballast and hence I haven't yet.
Trust me....I had this happen...and if I didn't watch it and become aware quickly...I could have been a statistic. I by-passed 60 miles and one lock from my home marina!
 
My boat came equipped with a 6 gal "water heater". It takes cold water and heats it up. These "hot water heaters", Where do you get them, and why would you heat up hot water?
Now that's scarsacm, Gary. Can't believe I beat you to this. LOL
 
sbw1 is correct -- flushing out the water system (several times) after having filled it with pink antifreeze takes a few minutes, but I prefer to purchase extra gallons of pink and fill the water heater when winterizing. This is the process my mechanic first recommended and it works well for me. As for bad taste, after the water system has been flushed out, add a teaspoon of pool/spa chlorine to your water tank and you'll be good to go.
 
Interesting - "hot water heater" is kind of an oxymoron.

Jumbo shrimp, plastic silverware, start stopping, controlled chaos, government worker, etc.
(just kidding government employees.)
 
rondds said:
Interesting - "hot water heater" is kind of an oxymoron. ...
Click to expand...

Actually ...once you get past the initial heating of cold water, your water heater spends most of its time re-heating already hot water....hence "Hot" water heater....just to look at it another way so to speak...:thumbsup:
 
Then shouldn't it then be called a "water heater/hot water re-heater." :smt101
 
10.4 Ron - I always think it's dumb when people say hot water heater. We don't say frozen food freezer or cold air conditioner or hot air furnace.
 
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