By-Passing Hot Water Heater

[lehighsail]

So every year I have suctioned all my freshwater lines and now I hear it may not be the best idea so I want to put AF in all my lines but want to bypass the water heater. Can someone take a guess at how to do that with my current set up? The thing that also has me stumped is why there is a line (blue Pex line on top) that goes from the hot water side to the cold water side. Thanks.

 

[Don S/V ILLusion]

We all hear lots of things...

Before you try to improve upon prior success, remember that the frozen water isn’t what bursts lines. It’s the air pressure in the void space of a closed line which is compressed by freezing water. In other words, a little bit of residual water in an otherwise open line won’t burst. Save the antifreeze .

 

[dlochner]

You seem to have a rather complex system. Without a good schematic, it will be difficult to answer the question you posed. By passing is pretty straight forward. Instead of the cold water going into the HW heater, it goes directly to the HW line with a valve in each to prevent water from entering the HW tank.

The issue with freezing is trapped water in an enclosed space without room for the ice when it expands. So long is there is room in the line for the water, then freezing is not a big issue. Since your system has worked for a number of years, I wouldn't bother changing it.

 

[Ron20324]

WHAT A MESS OF PIPES. iF THAT WERE MINE, I'd run one pipe from each OUTLET TO A MANIFOLD TO SEND THE OTHER PIPES TO WHERE
IT'S NEEDED IN THE BOAT. i HOPE YOU NEVER HAVE TO REPLACE THE WATER HEATER.

PICTURE 2, ON THE UPPER LEFT, THAT METAL DEVICE LOOKS LIKE A TEMPERING DEVICE. It looks like a knob on top, which is used to set the temperature limit of the hot water. Mine is 38C, 104 F.

Me, for the money I just fill the tank in case there is a pocket of water still therein.

 

[rpwillia]

Water Heater Bypass Winterizing Kit | West Marine

Check out our Water Heater Bypass Winterizing Kit and more from West Marine!

www.westmarine.com

 

[bawlmer]

It looks like you're in Jersey. You have to do something with it or it will freeze and break stuff. The best thing would be to bypass and drain it but with all of that plumbing I could not even tell you where to start. Plan B would be to displace all of the water with anti freeze. It is far from optimal and will be a real PITA to clear in the spring but it is still better than dealing with multiple cracked pipes and probably a damaged mixer valve.

 

[arf145]

Actually, I blow all my freshwater lines clear every year and haven't had a problem. For the Hot tank, I open the drain valve.

 

[DougM]

Drain the water heater. Disconnect the cold inlet and the hot outlet from the water heater. Connect the inlet line directly to the outlet line. Run antifreeze through until you see it coming out of the hot water faucet(s). Reconnect the hot and cold to the water heater in the spring and close the water heater drain.

 

[Scott T-Bird]

I'm in the camp with clearing the lines, draining the tanks and leaving everything open for the winter. Draining the water heater can be tricky. There is a pressure relief valve at the lowest point that I open, but that doesn't seem to drain the tank. The only way I get it completely drained is to disconnect hot and cold at the tank. I have to be ready with something to catch the water and a hose to drain it or it makes a mess. I crawl around lifting & wiggling the lines to make sure they have drained. I've never even bothered to blow out the lines. A little residual water in the tanks isn't going to do any damage. Plastic lines are way more forgiving than copper lines and they won't burst with residual water. Any place where there are metal fittings, I just give it a good shake to make sure water has left. I didn't have everything locked down and I disconnected all the fittings at the pressure pump & accumulater, drained the filter, etc. In my opinion, it was far easier to simply run down every point of possible water collection and clear it, disconnect everything at critical locations and leave the faucets open, than to pump antifreeze thru the system. Who wants to deal with that stuff in the spring?

I haven't done it in my new boat yet, and it may be more complicated with fixed low points that I can't drain … we'll see. In my opinion, if you can identify and clear all the low points, there is no need to add antifreeze when you know all the water has drained.

 

[dlochner]

If there are small amounts of water in the HW tank, it will freeze without causing any issues. When there are drains (Raritan tanks do not come with drains) they are not precisely at the bottom of the tank so some residual water remains and will freeze.

After dealing with the mess @Scott T-Bird laments with draining water in to the bilge, I added a T and ball valve at the tank inlet. The T is connected to a piece of vinyl hose with a ½" fitting at the end. When it is time to empty the tank, the hose is connected to a small pump which pumps the water into a 5 gallon bucket that can be emptied without making a mess.

I purchased a small 12 v diaphragm pump from Amazon and connected it to a 12v socket. Total cost was about $30 with all the pieces and parts. Avoiding 6 gallons of water in the bilge each fall, priceless.

When pumping the water, open up the pressure relief valve to all air into the tank.

 

[Justin_NSA]

That's quite the Rube Goldberg. You may have to trace the tubing and diagram it to get the whole picture.
One of my off season projects is to redo the lines to my heater so I can bypass it with a flick of some valves instead of disconnecting and reconnecting.

 

[Jake N Eggs]

The brass valve that has 3 lines going to it is a mixing valve which regulates the temperature of the hot water coming from the tank. I have the same "shit show" and decided that I wouldn't bypass. My procedure is to drain the water tank, drain the hot water heater, connect a bucket to the input of the fresh water pump and fill the system with antifreeze. Once the system is full from the external bucket I bleed the system through so that pure antifreeze comes out of the taps. I then drain the antifreeze from the water heater back into the antifreeze containers using the fresh water pump to force the antifreeze out. Obviously the feed to the fresh water pump needs to be disconnected and you have to have a hose on the drain valve. I use the collected antifreeze to winterize the head and engine. It takes about 6 gallons to fill the system and you collect about 5 back when you drain the water heater.

 

[dlochner]

Obviously the feed to the fresh water pump needs to be disconnected and you have to have a hose on the drain valve. I use the collected antifreeze to winterize the head and engine. It takes about 6 gallons to fill the system and you collect about 5 back when you drain the water heater.

It would be good to check the antifreeze with a refractometer to make sure it still provides enough protection. It might be diluted from water in the hoses and HW tank.

 

[Justin_NSA]

It would be good to check the antifreeze with a refractometer to make sure it still provides enough protection. It might be diluted from water in the hoses and HW tank.

I just added one of these to my Christmas wish list. I used the floaty balls tool when I flushed and filled a couple weeks ago. It was diluted after it circulated and had to be strengthened

 

[Scott T-Bird]

If there are small amounts of water in the HW tank, it will freeze without causing any issues. When there are drains (Raritan tanks do not come with drains) they are not precisely at the bottom of the tank so some residual water remains and will freeze.

After dealing with the mess @Scott T-Bird laments with draining water in to the bilge, I added a T and ball valve at the tank inlet. The T is connected to a piece of vinyl hose with a ½" fitting at the end. When it is time to empty the tank, the hose is connected to a small pump which pumps the water into a 5 gallon bucket that can be emptied without making a mess.

I purchased a small 12 v diaphragm pump from Amazon and connected it to a 12v socket. Total cost was about $30 with all the pieces and parts. Avoiding 6 gallons of water in the bilge each fall, priceless.

When pumping the water, open up the pressure relief valve to all air into the tank.

Ha, I only wish I was that organized. I'm usually unprepared and can't find the fitting and a hose to make the connection when I take off inlet fitting. I only wish the water would drain into the bilge. On Thunderbird, my water heater was mounted on a platform and any water that came out of the tank connection would spill into a compartment where I had my NMEA 2000 fittings for all of the electronics and eventually around the battery compartment. I always had to fashion some kind of funnel to capture and divert the water into the bilge, where it was easily discharged!

 

[dlochner]

Ha, I only wish I was that organized. I'm usually unprepared and can't find the fitting and a hose to make the connection when I take off inlet fitting. I only wish the water would drain into the bilge. On Thunderbird, my water heater was mounted on a platform and any water that came out of the tank connection would spill into a compartment where I had my NMEA 2000 fittings for all of the electronics and eventually around the battery compartment. I always had to fashion some kind of funnel to capture and divert the water into the bilge, where it was easily discharged!

When I replaced the HW tank I used fittings that would connect to standard SS ½" supply lines, like the ones that connect household sink faucets. It makes the connection very easy. The drain hose stays connected to HW tank, so it is easy to pull it out and connect it to the pump.

The winterizing kit fits in a 5 gallon bucket.



And includes a hose for the engine intake and one for the head intake and freshwater system. The HW drain hose connects to the supply tube with the large easy to tighten knob.



The AF jugs will sit in the bucket to prevent spilling all over the cabin sole. (been there done that )

 

[lehighsail]

Thanks for all the input but still no answers to my two questions. Yes, I understand it is a bit of a complex setup for no apparent reason.
1. How to bypass the water heater without taking all the brass fittings apart if it is possible?
2. What is that top blue line going from the hot water side to the cold water side in the first picture?

Thanks again for any ideas.

 

[dlochner]

Thanks for all the input but still no answers to my two questions. Yes, I understand it is a bit of a complex setup for no apparent reason.

Actually, it appears complex and it would be a lot easier to understand if we had a schematic of the plumbing. If you had drawn a schematic and shared it, you would find it is a pretty straight forward installation.

1. How to bypass the water heater without taking all the brass fittings apart if it is possible?

The brass fitting can stay. The PEX fittings will need to be removed.

2. What is that top blue line going from the hot water side to the cold water side in the first picture?

As suggested way back in Post #4, it looks like you have a tempering valve and the top blue line supplies cold water to the valve.

 

[TomY]

So every year I have suctioned all my freshwater lines and now I hear it may not be the best idea so I want to put AF in all my lines but want to bypass the water heater. Can someone take a guess at how to do that with my current set up? The thing that also has me stumped is why there is a line (blue Pex line on top) that goes from the hot water side to the cold water side. Thanks.

I can't follow your plumbing but to isolate your water heater, all you have to do is stop the flow of cold water to the water heater. Drain the water heater and leave the drain open. It is then isolated from your pressure system.

My boats plumbing system is simpler than most with 2 mixing valves; one in the galley and one in the head.

After I drain the WH (leave valve open) and the water tanks, I clamp the COLD supply line to the WH with a visgrip.

I know. I know, bad practice. And I've been planning to put a shut-off valve in there for the past 20 season. But it hasn't seemed to damage the hose(tough stuff). Maybe this year,....Figure a shut off in your PEX in the COLD supply line.

Then it is a simple matter of adding enough antifreeze to your tanks to fill you supply lines (it doesn't take much).

Run the cold in the galley and head until you see orange.

But what about the HW lines? Here's my trick: Open the HOT on your sink fixture. Next, push your palm against the diverter/sprayer on your sink fixture. Slowly...turn your COLD on. Your palm will stop the flow out of your faucet and send it backwards, into your valve body(that's why they're called 'mixing valves').

The antifreeze will flow through your mixing valve (faucet) and through the HW supply line, back to the hot water heater.

You'll hear the freshwater reverse in the HW supply line, forced by the antifreeze. You'll also hear it as it drains out of your water heater. You might need someone to watch to make sure the fresh water has cleared and antifreeze starts draining out of your water heater drain(then you know what's left in the bottom of WH is antifreeze). Once you see antifreeze coming out of the WH drain line, you know your HW line is full of antifreeze.

Hopefully you have that water heater drain piped to the bilge for seasonal draining.

That's it.

 

[TomY]

By the way, I love PEX tubing and use it in houses for both heating and domestic. But it can freeze and split. I've had homes flooded by baseboard radiation the froze. It's tougher than copper but also has it's limits.

I've recently uncovered a more disturbing PEX weakness. Rodents chew through it.

Don't panic! It happens regularly but is not too common (first time I've seen it in). In this case, the over sized hole the tubing was run through was a runway for mice. They tend to chew around openings to enlarge (I guess) and simply took a liking the PEX where it went through the hole. Destroyed a bathroom from the ceiling down. I've also had several romex circuits destroyed by squirrels this season. Amazing how much damage a tiny creature can do.