Can you tell me about the maintenance of the unit. Have been reading the specs very impressive, states that at 2 gpm the unit will use 20lbs of lpg to heat 940 gallons of hot water. Have not been able to find the max hot water output can you give me a idea.
We use a Bosch 38B. It weighs 18 lbs empty. It is rated between 20,000 BTU's to 40,000 btu's depending on pressure. At 13 psi it will put output 1.3 GPM and will handle up to 150 psi (not on my boat). I don't have exact gallons of lpg numbers but what we can do is adjust the flow rate with a dial on the front of it.
The work to keep it serviced is not much. Ours is bolted to the wall of the shower
and I can take off the cover in a minute and then start removing the parts
. It's pretty small in size and has no moving parts
. The unit has a small heat exchanger
surrounding the burner. You have to manually adjust the pilot valve to get the correct flame. It works exactly like natural gas a home hot water heater as far as lighting
it goes. I do not keep it lit all the time as I don't leave the propane
on all the time either.
The flow regulator
just slows the water flow and forces it to get hotter. It clearly is hotter than you need for a shower
even where you want to waste a lot of water. At lowest flow it's too hot to shower with and full flow it's perfect for sumertime showers. Both of these exclude mixing with cold water and of course you could do that. On the hook it's going to be be a lot less water so the lpg requirement drops (if you expect to keep a large supply of water). At the dock
you can take a 20 minute shower if you wanted to.
All I have to do is winterize it with antifreeze
. The instruction talks about lubricating the water valve every few years with a rebuild
perhaps on a 5 year interval. You can operate it with the cover off to inspect it easily. I find I have to adjust the pilot somewhat often. It's just a small wrench with the cover off to adjust it. It is exceptionally easy to disassemble. I wouldn't try that with a conventional tank.
As far as cost, the nice stainless 7 gallon tanks
work well so price
them as a comparisson. I had one in the last boat and they do heat fast and make enough water for two people and cleaning
the dishes after you run the engine
and the water is warm in the morning to a degree. Replacing a hot water tank is no picnic nor is installing one correctly so you gain a little bit on the installation
after you run a propane
line. You sure can't repair a hot water tank. The 38B is the only one that is ventless. How you would handle a vent is the perhaps only negative item I can think of since it has to go through the deck
Our unit was installed by the original owners in 1991 and they cruised 40,000 miles for 5 years. It was then lived aboard in Delaware for over a year (I'm confident it was used every day and was 100% neglected) and it still works fine. I wouldn't say they are temperamental.