Propane Water Heater

[JiffyLube]

I'm thinking about installing one of those pilot-less propane water heaters that makes instant hot water, and I'd be interested in hearing the pros and cons of these devices by people that have them. Do they make enough hot water on demand to replace a conventional marine water heater?

[Maine Sail]

Some of them can make plenty of water but unless they are sealed combustion with an intake and exhaust vent your insurance comapny won't like it much as they are not an approved appliance by marine standards. I know two people who have been told to remove on-demand "ventless" propane water heaters during an insurance survey. Something to think about before installation.

[mitiempo]

This is the only propane water heater I have ever seen that has no pilot light and a closed combustion system.
Precision Temp Boat Tankless Hot Water Heater. Gas Marine Water Heaters. Propane Boat Hot Water Heater

[Minnewaska]

Oh the horror.......

Seriously, you would require a charged propane line in the boat at all times and a flame would be ignited outside your view. This is unlike the galley, which is manually shut down when not needed and can/should be monitored when lit.

Sorry, it just sounds like a bad idea.

[JimPendoley]

I've got a propane water heater that I live aboard with quite comfortably. I also have a Dickinson Marine Propane Heater and a Seaward Stove/Oven. Given all of the saftey features, no pilot, O2 depletion shutdown-I feel that the risk is minimal. Seems a lot safer than running my oven...As for venting, I open a port in the head where it is located and enjoy a hot shower. I've also got a propane sniffer wired to a solenoid for auto shutoff in case of a leak.

That said, I'm sure an insurance company would balk, but its a risk I'm comfortable with. Living your life according to the dictates of an insurance company can be pretty limiting...
YMMV

[Minnewaska]

My horror comment may not come across correctly. It was tongue in cheek. Propane issues usually bring out the horror in us, when there are virtually no propane fires compared to other sources.

That could be due to better safety measures than electrical systems and engines. However, I don't like the potential of propane leaks down below. I've gotten in sword fights over how far one must go with the BBQ outside on the rail, where I seem to be less risk adverse than some others.

[Waltthesalt]

I have a bulkhead mounted Wolter instantaneous heater. It's a compact unit, I wouldn't have the space for the Precision unit.

I built separate control box (Radio Shack Project box) for the unit and installed it in the shower area. This includes power switch for the box, power switch for the unit and a switch for the propane solenoid. I also have a CO sensor/alarm in the shower area.

Per ABYC the heater has its own separate hose from the propane tank manifold and its own shutoff solenod valve controlled from the shower control box. So the propane line isn't pressurized except when the unit is in use. My unit and I think most curent RV units don't use pilot lights but have a 12 "igniter" that fires and starts when there's water demand. The gas shuts off when the demand stops.

My pressurized water system only serves the instantaneous heater, but my boat is small and the telephone shower head can reach to the head and galley sinks. The water's delivered at an adjustale usable temp so ther's no need to mix it with cold water. Those sinks use hand pump faucets as thier normal supply. I use two separate water tanks and supply systems as I didn't want to run the risk of a valve in the pressurized system being cracked open and unitnetionally pumping down the tanks. The hand pumps can switch between tanks but the pressurized system can't be cross connected.

My heater vents thru a 3 in. exhaust pipe thru the cabin top. Intallation requires a specific minium exhaust vent distance to get requisite flow so it doesn't back up. I think Wolter stopped production when someone was killed becase the unit wasn't properly vented and the exhaust gas backed up into the shower stall.

Instanteous water heaters for boats were once popular. The current trend appears to be a heater that us heated by engine cooling water of 112V heating elements in port. This requires quite a bit more space space that a bulkhead unit. I'd have to give up a quarter berth.

Wolter is long out of production now. I recall that Poloma, a japaenese company was a popular maker boats propane heaters. These had a pilot light however. From what I read on Sailnet, people with old Paloma heaters were being replacing them with Excel, heaters (no pilot light). Check out the thread.

As my Wolter is on its last legs the Excel looks like a reasonable replacement.

[Waltthesalt]

Someting else I or got. My heater/shower is in the head which has an opening ports and a hatch. I have have a sign on the heater that these should be partially open if the heater's being used. I woldn't put one in a head without good ventillation. Alternatively the heater could be located in the cockpit area. Wolter had a unit desigend for it. My control box also has a 1in diameter red light that's when it's energized

[MacGyverRI]

Originally Posted by Waltthesalt

Alternatively the heater could be located in the cockpit area.

I'm going to mount an "EZ-101 tank less heater" (made for camping/outdoors) on my back rails, it's about the size of a MOM unit and was $140.

I also have a "Safe-T-Alert" Fume Detection system inside for the Propane heater.

[jimrafford]

I'm currently in the process of installing the Precision Temp heater. I'm also installing a propane detector in the area where the heater will be. We're pretty conservative about our hot water use but I'm tired of no hot water to do the dishes after navy showers. Will know in a couple days how well it works.
Jim