Water Heater

[C. Novack]

I would like to add a hot water heater to my 28ft CD Open Sport Fisherman. The boat currently has a pressure cold water system. Should I use the same type piping CD used, that is, the grey flexible tubing with flare fittings or should I use half inch plastic pipe and glue the fittings? I presume that a 6 gallon heater will meet my requiremnents since only my wife and I will be overnighting. What type of hose should I be using to carry the hot water from the engine to the heat exchanger? Should I just put a "T" in the engine hot water hose? All thoughts/comments will be appreciated. Chris

[Bill Michne]

I would like to add a hot water heater to my 28ft CD Open Sport Fisherman. The boat currently has a pressure cold water system. Should I use the same type piping CD used, that is, the grey flexible tubing with flare fittings or should I use half inch plastic pipe and glue the fittings? I presume that a 6 gallon heater will meet my requiremnents since only my wife and I will be overnighting. What type of hose should I be using to carry the hot water from the engine to the heat exchanger? Should I just put a "T" in the engine hot water hose? All thoughts/comments will be appreciated. Chris

Chris:

The grey flexible tubing should be fine as that is what is on my boat and I've never had a problem. Six gallons should be plenty. Hose from the engine is just regular coolant hose, nothing special. Your heat exchanger may already be tapped and plugged; check it out.

Bill Michne
s/v Mintaka CD 40 #7

[Tom]

I doubt if you'll be able to find that gray flexible tubing. It was outlawed several years ago in most states. I used regular non-toxic water hose when I got rid of all my gray flex tubing that was leaking everywhere, but you can use half inch PVC if you want to go that way.
6 gallon size is what's readily available in water heaters and is what most people use. Fine for a quick shower for two people. If you're not raw water cooled and have an expansion tank for the engine coolant that's a handy spot to get into the hot coolant system rather than teeing off. Just pull the hose off the expansion tank on the intake side and put it on the intake side of the heat exchanger. Then run a hose between the exhaust of the heat exchanger and the intake of the expansion tank. Use the same hose that is everywhere else in the coolant system -- that heavy black rubber stuff. There's a schematic picture of the plumbing design in one of the sailboat manuals that you might be able to find, but if you can find a boat to look at it's easy to follow.

Be careful when tightening fittings on the water heater as they are easy to twist off. Hold the fitting you're screwing onto on the heater with a wrench so that you don't get torque applied to the fitting on the water heater. These aren't built as robust as the water heater in your house where it's all galvanized pipe that will take a beating. If you twist the fitting off it's not covered under warranty because it's owner error. You might also read through the threads about getting air bubbles out of the water heater. They usually get an air lock and cause your engine to overheat when they are first put in if they are higher than the engine. It's a trick to get the air out on a new installation sometimes, and it will drive you crazy trying to figure out why the engine is overheating when everything seems to be OK and it's not leaking.

When you hook up the 120 volt electric to the water heater be sure to have water in the tank before turning it on or you will burn up your new heating coil.

I hope I've covered all the potential pitfalls. Good luck.

I would like to add a hot water heater to my 28ft CD Open Sport Fisherman. The boat currently has a pressure cold water system. Should I use the same type piping CD used, that is, the grey flexible tubing with flare fittings or should I use half inch plastic pipe and glue the fittings? I presume that a 6 gallon heater will meet my requiremnents since only my wife and I will be overnighting. What type of hose should I be using to carry the hot water from the engine to the heat exchanger? Should I just put a "T" in the engine hot water hose? All thoughts/comments will be appreciated. Chris

TomCambria@mindspring.com

[Bill Michne]

I doubt if you'll be able to find that gray flexible tubing. It was outlawed several years ago in most states. I used regular non-toxic water hose when I got rid of all my gray flex tubing that was leaking everywhere, but you can use half inch PVC if you want to go that way.
6 gallon size is what's readily available in water heaters and is what most people use. Fine for a quick shower for two people. If you're not raw water cooled and have an expansion tank for the engine coolant that's a handy spot to get into the hot coolant system rather than teeing off. Just pull the hose off the expansion tank on the intake side and put it on the intake side of the heat exchanger. Then run a hose between the exhaust of the heat exchanger and the intake of the expansion tank. Use the same hose that is everywhere else in the coolant system -- that heavy black rubber stuff. There's a schematic picture of the plumbing design in one of the sailboat manuals that you might be able to find, but if you can find a boat to look at it's easy to follow.

Be careful when tightening fittings on the water heater as they are easy to twist off. Hold the fitting you're screwing onto on the heater with a wrench so that you don't get torque applied to the fitting on the water heater. These aren't built as robust as the water heater in your house where it's all galvanized pipe that will take a beating. If you twist the fitting off it's not covered under warranty because it's owner error. You might also read through the threads about getting air bubbles out of the water heater. They usually get an air lock and cause your engine to overheat when they are first put in if they are higher than the engine. It's a trick to get the air out on a new installation sometimes, and it will drive you crazy trying to figure out why the engine is overheating when everything seems to be OK and it's not leaking.

When you hook up the 120 volt electric to the water heater be sure to have water in the tank before turning it on or you will burn up your new heating coil.

I hope I've covered all the potential pitfalls. Good luck.

I would like to add a hot water heater to my 28ft CD Open Sport Fisherman. The boat currently has a pressure cold water system. Should I use the same type piping CD used, that is, the grey flexible tubing with flare fittings or should I use half inch plastic pipe and glue the fittings? I presume that a 6 gallon heater will meet my requiremnents since only my wife and I will be overnighting. What type of hose should I be using to carry the hot water from the engine to the heat exchanger? Should I just put a "T" in the engine hot water hose? All thoughts/comments will be appreciated. Chris

Chris:
That gray tubing: when and why was it outlawed? All the pressurized plumbing in my boat is made of it.
Bill Michne

[Tom]

The way I got the story from a plumber is that they started using it to plumb new houses. Some of the fittings blew off in time and the builders and home owners sued the manufacturer. There was a big lawsuit over it for millions of dollars which caused the manufactureer to stop making it because of the liabilities involved. As a result building codes deleted it as an approved material.

It might be OK on boats where it's used intermittently and the pressures usually aren't as high as in city water systems, but apparently the market isn't big enough to make it worth risking the liabilities involved. I have no proof of this, it's just what a plumber told me, but I haven't seen it in stores for about 10 years at least out here in Calif. You might try RV stores as it may be approved for that in some states.

I doubt if you'll be able to find that gray flexible tubing. It was outlawed several years ago in most states. I used regular non-toxic water hose when I got rid of all my gray flex tubing that was leaking everywhere, but you can use half inch PVC if you want to go that way.
6 gallon size is what's readily available in water heaters and is what most people use. Fine for a quick shower for two people. If you're not raw water cooled and have an expansion tank for the engine coolant that's a handy spot to get into the hot coolant system rather than teeing off. Just pull the hose off the expansion tank on the intake side and put it on the intake side of the heat exchanger. Then run a hose between the exhaust of the heat exchanger and the intake of the expansion tank. Use the same hose that is everywhere else in the coolant system -- that heavy black rubber stuff. There's a schematic picture of the plumbing design in one of the sailboat manuals that you might be able to find, but if you can find a boat to look at it's easy to follow.

Be careful when tightening fittings on the water heater as they are easy to twist off. Hold the fitting you're screwing onto on the heater with a wrench so that you don't get torque applied to the fitting on the water heater. These aren't built as robust as the water heater in your house where it's all galvanized pipe that will take a beating. If you twist the fitting off it's not covered under warranty because it's owner error. You might also read through the threads about getting air bubbles out of the water heater. They usually get an air lock and cause your engine to overheat when they are first put in if they are higher than the engine. It's a trick to get the air out on a new installation sometimes, and it will drive you crazy trying to figure out why the engine is overheating when everything seems to be OK and it's not leaking.

When you hook up the 120 volt electric to the water heater be sure to have water in the tank before turning it on or you will burn up your new heating coil.

I hope I've covered all the potential pitfalls. Good luck.

I would like to add a hot water heater to my 28ft CD Open Sport Fisherman. The boat currently has a pressure cold water system. Should I use the same type piping CD used, that is, the grey flexible tubing with flare fittings or should I use half inch plastic pipe and glue the fittings? I presume that a 6 gallon heater will meet my requiremnents since only my wife and I will be overnighting. What type of hose should I be using to carry the hot water from the engine to the heat exchanger? Should I just put a "T" in the engine hot water hose? All thoughts/comments will be appreciated. Chris

Chris:
That gray tubing: when and why was it outlawed? All the pressurized plumbing in my boat is made of it.
Bill Michne

TomCambria@mindspring.com

[Boyd]

I am an architect and the story you got from the plumber is essentially true. The fittings used on houses were a crimped fitting. Different from the screw on type on my boat. Last time I checked Home Depot still had some stock in the tubing and parts. The stuff is still legal...just nobody wants it. They have improved the crimped fittings so that they work now... they say. I would use the grey stuff with screw on fittings on my boat for new projects as I have had no problems with it. The westerbeke manual for my boat has quite a bit of info on how to install a water heater and expansion tank. Let me know if you would like a snail mail copy.

Boyd

The way I got the story from a plumber is that they started using it to plumb new houses. Some of the fittings blew off in time and the builders and home owners sued the manufacturer. There was a big lawsuit over it for millions of dollars which caused the manufactureer to stop making it because of the liabilities involved. As a result building codes deleted it as an approved material.

It might be OK on boats where it's used intermittently and the pressures usually aren't as high as in city water systems, but apparently the market isn't big enough to make it worth risking the liabilities involved. I have no proof of this, it's just what a plumber told me, but I haven't seen it in stores for about 10 years at least out here in Calif. You might try RV stores as it may be approved for that in some states.

I doubt if you'll be able to find that gray flexible tubing. It was outlawed several years ago in most states. I used regular non-toxic water hose when I got rid of all my gray flex tubing that was leaking everywhere, but you can use half inch PVC if you want to go that way.
6 gallon size is what's readily available in water heaters and is what most people use. Fine for a quick shower for two people. If you're not raw water cooled and have an expansion tank for the engine coolant that's a handy spot to get into the hot coolant system rather than teeing off. Just pull the hose off the expansion tank on the intake side and put it on the intake side of the heat exchanger. Then run a hose between the exhaust of the heat exchanger and the intake of the expansion tank. Use the same hose that is everywhere else in the coolant system -- that heavy black rubber stuff. There's a schematic picture of the plumbing design in one of the sailboat manuals that you might be able to find, but if you can find a boat to look at it's easy to follow.

Be careful when tightening fittings on the water heater as they are easy to twist off. Hold the fitting you're screwing onto on the heater with a wrench so that you don't get torque applied to the fitting on the water heater. These aren't built as robust as the water heater in your house where it's all galvanized pipe that will take a beating. If you twist the fitting off it's not covered under warranty because it's owner error. You might also read through the threads about getting air bubbles out of the water heater. They usually get an air lock and cause your engine to overheat when they are first put in if they are higher than the engine. It's a trick to get the air out on a new installation sometimes, and it will drive you crazy trying to figure out why the engine is overheating when everything seems to be OK and it's not leaking.

When you hook up the 120 volt electric to the water heater be sure to have water in the tank before turning it on or you will burn up your new heating coil.

I hope I've covered all the potential pitfalls. Good luck.

Chris:
That gray tubing: when and why was it outlawed? All the pressurized plumbing in my boat is made of it.
Bill Michne

Tern30@aol.com

[D. Stump, Hanalei]

Surge tanks (what has been refered to as expansion tanks) are available from Sen-Dure in Fort Lauderdale, FL. There number is (954)977-8731. Talk to Ron Schaper. For a six gallon w/h a tank that is about 10 inches long with a diameter of about 2-3 inches is what you need. Ron can help you. These tanks are NOT cheap, so stand by!