Tankless Water Heater

rnbenton

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My water heater has expired (leaking) and will need to be replaced right away. Anyone have any experience with the tankless water heaters? Seems like they would be compact and light weight, if they work well.

So, I'd like to hear if anyone has one or has knowledge of them.
 
Interesting idea. However, they consume a huge amount of energy when they're operating. The smallest electric ones use about 10KW. Gas ones might fill your needs if you already have a gas system on your boat.
 
Forget it if you are considering electric. They require very large amounts of current even at the 250v level. Take a look at the units and their input requirements. Then look at your shore power connection. It should quickly convince you that while the notion is nobel, it's futile.
 
I looked into this seriously and found the current needed is barely there and depending on your generator may not be there. If you don't mind taking luke nwarm showers and everything else AC wise must be off then the tankless heater is for you. If your like me and like the free hot water from the exchanger in my standard ignition protected Atwood get a conventional boat heater. I keep mine turned up high and can get 2 fairly long showers without turning off anything else in the boat when taking a shower.
Bill
 
Same experience as the rest.. Too much draw to be effective on a boat.
 
Also keep in mind that the tankless heater may not be rated for placement on a gasoline powered boat, if that is what you have.
Remember, GF + RAM + S = BB (Gas Fumes + Right Air Mixture + Spark = Big Boom). This formula does not address the usual resultant large fire that accompanies the BB.
Just another Schnuk
 
Yep, found several tankless heaters for Marine use and certified for a Gas boat, which is what I have.

But, the guys are right, the power requirements are way high. Even on shore power almost everything else would have to be turned off.

So, regular water heater with heat exchanger it is. :)

quote:

Originally posted by schnuk42

Also keep in mind that the tankless heater may not be rated for placement on a gasoline powered boat, if that is what you have.
Remember, GF + RAM + S = BB (Gas Fumes + Right Air Mixture + Spark = Big Boom). This formula does not address the usual resultant large fire that accompanies the BB.
Just another Schnuk




 
Jim good move believe me I have made many bad moves and needed to make changes in rebuilding my boat. This was one mistake I am glad I didn't make. If you can fit a 10-12 gallon water heater Raritan and Atwood are both great. I prefer the Atwood because it is polished stainless, rectangular, I believe 11 gallons and extremely well insulated. I normally turn my hot water heater off at night and 6 -7 hours later we still have enough hot water enough for a quick splash when shaving and washing hands and face in the morning. Then if we run the engines we have plenty of hot water to take a shower without turning on the breaker. To me just too many pluses vs. the negatives of a tank-less electric ignition protected heater.
Bill
 
Our boat has flaired copper plumbing and we don't need to run the water heater to the engine to have hot water. Just leaving the electric on, and a hose on the fordeck in the sun is usually enough for plenty of hot water. Just make sure you have a whole house filter at the water inlet to the boat. It stops the algae. And use an opaque filter housing since the algae grows on the 2 micron carbon filters faster with the sunlight the clear filter housings let in.
 
We have the 25 amp unit on our boat. Our boat is a 30 amp boat. We can run it on generator or shore power.
We do have to turn off the a/c when we run the water heater, but that isn't long because we only have a
25 gallon water tank. No long showers for us.
It works well, but we cannot run cold water thru it at the same time.. We only turn on the hot water.
It comes with a certain sized orifice for it so you cannot run too much thru it to cool it down. The original
owners removed the water heater and installed a generator in it's place. We have no other choice except to
take cold showers.
The marine units we found come in 20, 25 and 30 amp. The higher the amps, the higher the temperature and the
higher the water rate you can pass thru it.
I don't think 25 amps is too much. We do not regret installing it. It is installed under the head sink, it is
small and easy to hook up.
 
What make and model do you have?

quote:

Originally posted by rduhon

We have the 25 amp unit on our boat. Our boat is a 30 amp boat. We can run it on generator or shore power.
We do have to turn off the a/c when we run the water heater, but that isn't long because we only have a
25 gallon water tank. No long showers for us.
It works well, but we cannot run cold water thru it at the same time.. We only turn on the hot water.
It comes with a certain sized orifice for it so you cannot run too much thru it to cool it down. The original
owners removed the water heater and installed a generator in it's place. We have no other choice except to
take cold showers.
The marine units we found come in 20, 25 and 30 amp. The higher the amps, the higher the temperature and the
higher the water rate you can pass thru it.
I don't think 25 amps is too much. We do not regret installing it. It is installed under the head sink, it is
small and easy to hook up.




 
We have an EEmax 25 amp unit. Don't remember the model number. It is
made for boats, not houses. All plastic and stainless steel.
 
OK, job done. Found a Seaward F1200, all stainless,w/heat exchanger, on E-Bay for $202.50. Bought it, installed it and now showering in warm water bliss.

Thanks all for your input and advice.

quote:

Originally posted by rnbenton




 
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