Tankless Propane Water Heater ?

[hellosailor]

Mitchell, water heaters just heat water. They've got nothing to do with your water pressure. Whatever water pressure you have in your cold water system, is what you'll have in your heated cold water.

[clockwork orange]

My Gemini just has the usual jabsco pump at the tank.

Steve.

[mmr]

Thanks, Steve, cwyckham, and hellosailor

From your three responses I can piece together the answer I need.

Mitchell

[wolfenzee]

Something that was drilled into me was "never leave an unattended flame"....if you have to leave the cabin for anything or any amount of time, you turn off your stove (I have put out fires on neighboring boats, that were the result of an unattended flame) , when you are not using water the L5 turns off automatically (and sparks automatically using a D-cell when you have water flow).....and when you are done using it you turn off the propane flow like any propane appliance

[unbusted67]

It seems like there is a hole in the market for this sort of thing. All of the models people have listed on this forum seem to be camping grade gear and not marine grade. If West Marine, Jabsco, Atwater, or Searay decided to market a Marine grade, on demand, propane, or propane/electric water heater, for which the installation instructions complied with ABYC standards, well, you'd have yourself a sale-able item.

I especially like the idea of a hybrid system where you could run a standard tank heater off of shore power when plugged in, a heat exchanger when under way, and off of propane when at anchor. Maybe I should design it!

[Cheechako]

Originally Posted by unbusted67

It seems like there is a hole in the market for this sort of thing. All of the models people have listed on this forum seem to be camping grade gear and not marine grade. If West Marine, Jabsco, Atwater, or Searay decided to market a Marine grade, on demand, propane, or propane/electric water heater, for which the installation instructions complied with ABYC standards, well, you'd have yourself a sale-able item.

I especially like the idea of a hybrid system where you could run a standard tank heater off of shore power when plugged in, a heat exchanger when under way, and off of propane when at anchor. Maybe I should design it!

I've had them on two boats; a Paloma unit in the 80's and more recently an Eccotemp L5. The Eccotemp appears to have all the safety features and maybe more than any other marine gas device. It works alot better than the old Paloma did... much more uniform water temperature. It also has a Piezo lighter.
It's all about how you use it. You wouldnt leave your cook stove oven pilot on all the time would you? I just light mine each time I use it... just like the cook stove. The Eccotemp L5 at about $125 is a real bargain. Both my installations had the unit right below an overhead hatch. You could duct it if that concerns you more than your cookstove does....
Let's face it... there are some people who shouldnt be using gas appliances of any kind and there are some who can manage their systems well....

[hellosailor]

Ben-
I think it is more of a problem of the market being too tiny and complex.
Would someone plumb propane on to a boat JUST for the dual heater? Probably not, they'd also be using it for cooking. So now there's a need for professional installation and a more complex propane system, which like the stove probably needs another solenoid to shut it off when not in use. Starts to become expensive, and more so when customers either call for installation help, or have a problem and sue after the explosion.

Not impossible--just something that sounds like there's no real sure profit motive left for the maker.

[Maine Sail]

Originally Posted by charlie p

I think the comment about ABYC not considering tankless heaters when defining "attended" vs "unattended" has merit.

Our PDQ cat had an expensive Bosch tankless with a pilot light. We never used it because every time we turned off the propane solenoid, the pilot went out and it was a pain to light. Also, I just didn't like the whole pilot light idea. I replaced it with an inexpensive Eccotemp L5 in the galley.

Before, the sequence for washing dishes was

1. Fill kettle, turn on propane, light cooktop.
2. Go to salon or on deck, wait for kettle whistle.
3. Turn off cooktop and propane, wash dishes.

After the L5 install

1. Turn on propane.
2. Wash dishes, using on demand hot water as needed.
3. Turn off propane.

This is where the ABYC definition is a bit amusing.

Note that in the first case (ABYC approved), the "attended" device is unattended while in the second case (ABYC unapproved) the "unattended" device is attended. This is not a made up example.

ABYC has done a lot of good work, (e.g. not allowing pilot lights) but sometimes their Rule-centric Reality is a bit much.

Also, A question about the dripping faucet scenario. Does anyone actually leave their boat or go to sleep without turning off the propane???? We sure don't.

Their ABYC's rule centric reality stems from actual deaths involving on-demand fired water heaters. When people die, standards change.

FWIW I just had the attended vs. unattended clarified for me last week by the ABYC. This ran all the way up to John Adey who is the President of the ABYC and also included Brian Goodwin the ABYC Technical Director...

The ABYC stands by the definition that an ON-DEMAND water heater is an UNATTENDED appliance, like it or not.

The reason I asked the for standards clarification is because an on-demand water heater manufacturer tried to tell one of my customers that his water heater was an "attended" appliance. This was UNTRUE as defined by the ABYC safety standards.

Please be careful because some of these manufacturers think they can simply fool customers into believing the appliance meets the standards. I have already had to physically remove an on-demand heater that failed an insurance survey. The customer was LIVID that the water heater manufacturer blatantly lied to him about it being "marine"....

Every manufacturer, installer etc.. has the ability to challenge the standards and show that their system is safe or show good reason why the rule should be modified or changed. According to the ABYC they have never heard from the manufacturer who told my customer that his heater is an "attended" appliance...

I called the ABYC on behalf of my customer, because I told him I would not install the heater without standards clarification on this matter.

The bottom line, straight from the ABYC, is that any on-demand propane or CNG fired hot water heater is still considered an UNATTENDED appliance and falls under the UNATTENDED appliance rules. Is this right, wrong or indifferent? I can't say, but as of yet, according to my conversation last week, no manufacturer has had the gusto to challenge it.

Insurance companies follow ABYC standards as do surveyors. Unless someone comes up with a sealed combustion propane fired on-demand propane water heater, someone should, none of them currently meet the safety standards that I know of...

I am not saying they are safe, or not safe here. I am just saying that they do not meet the current accepted safety standards. I have had to remove them per insurance survey, this is just a reality. If you need insurance you could get stung if it does not meet the current safety standards...

[hellosailor]

Maine-
So, I think we would all agree that the ABYC is right, if you consider that a typical on-demand propane flash heater can be turned on by a leaking faucet or burst pipe, when then creates an unattended, unsupervised, demand on the water which then turns on the propane.

Solution to that would appear to be easy-peasy. Install a 1/4 turn ballcock on the water line right "at" the flash heater. That can't operate without supervision and attendance, so now the flash heater is no longer an unattended device, is it?

Should be easy enough for the makers to just screw in that ball valve and fix it in place before the rest leaves the factory. And no further permission from ABYC would be needed, since it was no longer capable of unsupervised operation. Would it?

I sadly not amazed that none of these guys tries to FIND SOLUTIONS instead of saying "Nyet, nyet nyet!" and banging their shoes on the table, Nikita Khruschev style.

(Hey, they don't like that rabbit? Surely there must be other ones in the hat.)

[valhalla360]

I wouldn't put a lot of stock in the abyc response. I'm certain this is not what they had in mind when they said propane water heaters are not acceptable. When you corner an organization on a subject they have no interest in pursuing and it would take them time and effort to really check it out, the standard response is "no".

Insurance companies typically require a full survey on cruising size boats. As long as it clearly states you have an on demand propane water heater in the survey and they don't challenge you on it, the insurance company will be fighting an up hill battle if they try to deny a claim based on the water heater.

Lots of boats out there with these as standard equipment.

[Tony B]

I think the personal solution would be to use a remote shut-off valve for the propane tank - just the flip of a switch. We did that all of the time with out old Catalina 30. We had the gas sniffer, auto and manual remote shut off's. This has always worked for us.
I'm sure it would not be legal in this particular case because of the unattended thing, but I would feel safe with it. Unfortunately. boaters are not any different than the ordinary citizen. There exists a large enough population of irresponsible people that would not be bothered with having to flip a switch every time they used the appliance and that's why we have laws. Too bad these people couldn't kill themselves off with injury or damage to personal property to others.

[Maine Sail]

Originally Posted by valhalla360

I wouldn't put a lot of stock in the abyc response. I'm certain this is not what they had in mind when they said propane water heaters are not acceptable. When you corner an organization on a subject they have no interest in pursuing and it would take them time and effort to really check it out, the standard response is "no".

Insurance companies typically require a full survey on cruising size boats. As long as it clearly states you have an on demand propane water heater in the survey and they don't challenge you on it, the insurance company will be fighting an up hill battle if they try to deny a claim based on the water heater.

Lots of boats out there with these as standard equipment.

The ABYC has NEVER, EVER said propane water heaters are not acceptable. EVER.. They do however require all propane devices, whether they be attended or unattended devices, to meet minimum safety requirements.

You may get lucky with a poor surveyor and have them overlook it or look the other way on a water heater installation, but most good ones are going to spot it and document it.

Can someone name a builder building to ABYC or NMMA standards that is currently installing on-demand gas water heaters?

I would love to see more boaters join the ABYC, get involved in the safety standards process, and see how standards development really works....

[darylat8750]

If all it would take is a switched solenoid valve like is used for lp cook stoves it shouldn't be rocket science to figure out a circuit that would work.

[minaret]

Why would anyone with a Diesel engine use a propane on demand system when diesel fired systems like the Everhot exist?

[unbusted67]

Because ever hot requires an adaptable diesel water heater to pair it with. Those aren't easy to come by. The only one I know of is the Dickinson Alaska. Correct me if I'm wrong...