Raritan hot water heater

32carv

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(Also posted in the plumbing forum)

I have a Raritan 120v, 12 gallon hot water heater with a heat exchanger. I filled the tank with water today and turned on the pump and just got cold and none on the hot side. I pulled off the check valve and it was stuck shut so I "unstuck" it.

When I put it back together I got water from the hot side but light on pressure and the pump would not shut down. Could not find a leak until I happen to go to the back of the boat and saw water streaming out of the exhaust on the starbord side.

My theory is that the heat exchanger in the heater is broken and the water is just going through the engine at out the back. I am assuming that it needs a new heater which is about $700 plus labor if I pay someone to do it.

Is this normal wear and tear or a poor winterization job by my mechanic?

Jim
 
Jim, not having given me any indication of how old your water heater is, the cause could be either of the two possibilities you listed.

Temporarily, the engine coolant hoses can be disconnected from the water heater and joined together, then the two fittings for the heat exchanger can be removed and the two female threaded fittings plugged off. This will allow the water heater to be still used electrically, but not via the engine coolant method.

My guess would be that the tubing (coil) inside the water heater that is connected to the engine coolant lines was allowed to freeze, but I can't be sure - and don't want to throw any darts. If the unit is quite old, it may simply have deteriorated away with age.
 
I'm not sure of the age. Could be the original 1985 heater. It looks new from the outside but I know that may not mean anything. What are the tubes on the inside made of? My thought is to replace with a 12 gallon Attwood heater with heat exchanger that I can get for about $340.
Jim
 
Jim,

I believe you are thinking right to replace. That gives you more peace of mind that when the "fix" is made the fix is right. Patching the current one may only be covering up another problem that will rear its' ugly head at the worst possible moment.
 
Jim, if it has a metal exterior the tubes inside are copper. If it has a plastic exterior, the coil inside is steel.

The metal exterior was used prior to 1995. Since 1995, all Raritan water heaters have a fire-resistant plastic outer cover.
 
It has a metal exterior so they must be copper. What would cause copper to fail?
Jim
 
Personally, I like the idea above of changing to a tankless water heater. A local friend just replaced his 1986 vintage tank heater with a new "instant" water heater. Works really well. True, he only has hot water with the genny running or on shore power. But, works very well.

quote:

Originally posted by 32carv




 
We took out the heat exchanger today and one of the copper tubes is pulled off of the unit. Can it be repaired? Can I buy the whole heat exchanger?
Jim
 
Did you e-mail me at the plant? I had an inquiry this morning in my e-mail. Anyway, we no longer offer replacement heat exchangers for those older water heaters (pre-1995).

But if you can get the tube back into place, it can be re-soldered. You'll likely need to take it to a weld shop and have them solder it back in place using a torch and Mapp gas. The standard handyman's propane torch won't generate enought heat to do the job.
 
Yes, that was me. I'll give it a try.
Thanks,
Jim
 
quote:

Originally posted by 32carv

I'm not sure of the age. Could be the original 1985 heater. .......





That's 24 years old! Two to three times the life of a residential water heater. I'd say you have gotten your money's worth. Time to replace it.
 
quote:

Originally posted by 32carv

I have a Raritan 120v, 12 gallon hot water heater .........





In the words of my friend the plumber, "Why would you want to heat water if its already hot?"
 
I am picking up my "cold water heater" this week and the cost for fixing it was $15. If it doesn't work I will spend the $340 on a 10 gallon Attwood. Would like to replace it with a Raritan but at $700 to $800, I think I'll pass.
Jim
 
quote:

Originally posted by 32carv

I am picking up my "cold water heater" this week and the cost for fixing it was $15. If it doesn't work I will spend the $340 on a 10 gallon Attwood. Would like to replace it with a Raritan but at $700 to $800, I think I'll pass.
Jim






I wondererd why they were that much more expensive. Is the construction that much better?
 
They are designed for the marine environment and are all ignition-protected, for mounting below deck with gasoline fueled engines. It isn't unusual for them to last 25-30 years. Try that with an Attwood...!
 
quote:

Originally posted by Vic Willman

They are designed for the marine environment and are all ignition-protected, for mounting below deck with gasoline fueled engines. It isn't unusual for them to last 25-30 years. Try that with an Attwood...!






Thanks Vic. With respect, dollarwise, it's a wash shy the VLPITA of removal and reinstall of an Attwood 3 times.

I shall buy a Raritan when I buy the "last boat". I have narrowed the find for the "last boat", I just haven't found the cash!!!!!
 
quote:

Originally posted by rnbenton

Personally, I like the idea above of changing to a tankless water heater. A local friend just replaced his 1986 vintage tank heater with a new "instant" water heater. Works really well. True, he only has hot water with the genny running or on shore power. But, works very well.

quote:

Originally posted by 32carv












I curerntly have a 20gallon 110v water heater on board now with no heat exchanger. It looks like a Short fat stubby house water heater. I can only use the hot water at dock or run the generator for 20 minutes for hot water. Personally I would rather have the tankless for space and weight reasons and to start the generator and have instant hot water.
 
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