View Single Post
Old 02-28-2014, 10:22 AM   #11
City: North Charleston, SC
Country: USA
Join Date: Sep 2010
Posts: 4,385
Originally Posted by Wilson View Post
Don't want to get into "fried my engine cause of my water heater" type issues that I have been reading about. Hot water is just not that important on this boat. I just want some at times. I'll have a fairly decent amount of batter power on board, couple big D's and a few deep cycle. I don't see why I couldn't run an on demand system off battery power seeing as how the alternator should be charging the batteries as we go along anyway. I could be wrong, thats why I asked is all. On demand systems are pretty cheap as well. My parents run an entire house off battery power in baja, find it hard to believe I couldn't run a boat the same way...
That water heater needs a lot of electrical power. You would need a bilge full of batteries and a humongous inverter to power it and the engine's alternator would take many hours to recharge the batteries. It's simply not practical on most boats unless you have a genset.

There is nothing wrong with heating water using engine coolant and it's "free".

Look around at other boats, especially production boats. These people have figured out what works and what doesn't. They have already considered what you are proposing and figured out that it's not the best solution.
rwidman is offline   Reply With Quote