Best on demand Propane water heaters Australia & NZ?

[Fore and Aft]

Franziska 90% of the boats I survey here in Australia have the heat exchange type water heater or a 12 volt water heater like the one in the link below. Certainly it is a rare boat that still has the gas water heater below decks. All the boats I survey that have gas hot water have the unit mounted on a bulkhead in the cockpit.
Cheers
https://www.keoghsmarine.com.au/new-...howers-duoetto

[ncohen226]

We have an Eccotemp permanently plumbed into our fresh water system and it works perfectly. We attached it to our pushpit rail and connected it directly to a propane cylinder in the gas locker. We had it done by a gas fitter in our marina service centre and had our insurance company sign off on the install.

We bought a second Eccotemp as a back up and keep it on board

They are about $125 Cad each from Walmart

[Cheechako]

The last one I had was a camping unit and far superior to the Paloma I had years ago. Safety features etc. I always only kept mine lit when using and turned off like the propane stove otherwise. It kept nice even water temp, unlike the Paloma.
Eccotemp L5 $130
https://www.build.com/product/summar...E&gclsrc=aw.ds

[Mike Banks]

Yes it is correct--or was when I owned mine, but the installation must be checked and tested by a registered gasfitter and the apparatus must be suitable for the purpose.

I had a Saxon system in mine originally. I replaced it with a Bosch--which was FAR superior, produced all the hot water I needed, was temperature-adjustable had a good display panel and was self-igniting.

The company itself refused to guarantee it if used in other than a domestic dwelling--and it is a moot point as to whether or not a liveaboard vessel is a domestic dwelling--but the installation was entirely to code and I had the gas-detection system sensors in the bilges and galley.

When I sold the vessel I removed the system. I was delighted with it and it worked fine with the pressure water system on board using the vessel's freshwater tanks, or the marina mains water supply. It cost me just over two grand installed--

Which brings up another point. I could have, had I foregone a little convenience, had a solar-system with a hot water storage facility for that kind of money, and had no gas bills to pay--even though the system was incredibly efficient compared to the previous system installed which was a gas guzzler.

[BruceS]

3 of facebook as we speak.
https://www.facebook.com/marketplace...code=undefined
Most houseboats use these.

[Marathon1150]

We have a Rinnai brand on-demand hot water heater on our house in New Zealand. It is mounted outside and works perfectly - it will produce hot water continuously. I have seen similar units (also Rinnai) inside boats, usually in the galley, also in NZ. I hate to talk about it but it has been running daily for more than 20 years without an issue. They are Japanese and ours was made in Japan.

I also note one post above regarding the Hydronic system. If I had the money, I would install one of these. We have an Espar forced air heater on one of our boats which works very well in terms of heating the boat but the Hydronic version heats the cabin and makes hot water for domestic use, and takes up less space to distribute the heat.

[thinwater]

Originally Posted by Rucksta

So what's the restriction on mounting propane water heaters inside a boat?

Is it toxic combustion by products, hot exhaust, oxygen depletion?
Good ventilation would take care of that without the need for ducting...

Not really. The problem is that the firing rate of an instant heater is MUCH greater than a stove. Imagine a stove burner that could heat one gallon water from cold to warm in a minute. BTU ratings are typically 25,000-35,000 vs. 6,000 for a stove burner. That is also a lot of exhaust to dissipate in a small space.


ABYC requires an exhaust stack. It's the smart way to do it. Without the stack, survey and insurance could be a problem.

[Discovery 15797]

Like Ann, I also have a Paloma and I love it.

I have only found 1 model that satisfies ABYC standards, and also your requirements, but it is quite pricey.

https://precisiontemp.com/products/showermate-m-550/

[Jim Cate]

Originally Posted by JPA Cate

On our old unit, it is s/s pipe, 4" diameter, with heavy fiberglass insulation at the deck penetration. It is roughy 2 ft. tall (sorry for the English measures). Over the top, outside, is a screw down vent, for passagemaking, and it has worked well to keep water out.

Our propane tanks are in the lazarette, so it is a long run to the shower. We have a solenoid back there to allow the fuel to flow, that has to be switched on, and louvres in the door, so it is well ventilated, even when the port is closed. In the shower, one also has to turn on the gas. Our shower is equipped with a fan, that blows when the water pump is energized. The water and outside temperature seem to affect how much flame one needs to heat the water. Expect to have to fiddle with it a bit, before you know just how to adjust the temperatures for you.


Ann

To amplify Ann's description a bit...

The heater's main burner will not come on without water flowing through the heat exchanger. There is a muffin fan which takes air from the saloon and blows it into the head, and that fan comes on when power to the pressure pump is activated. The door to the head is louvered, allowing flow from the head into the saloon when the heater is heating. Intake air for the burner is also taken from the head airspace, increasing the inflow somewhat. The large (4" diameter) exhaust flue efficiently extracts the combustion products and waste heat directly through the overhead... less than 18 inches total length, so low pumping losses.

There is, besides the main solenoid valve at the tank, a gas valve just at the inlet to the heater, which is always shut off when the unit is not in use. Thus in standby mode there are three closed valves: solenoid, manual valve and the internal valve which is triggered by flow.

I do not know how this relates to the rules in the various places we've sailed the boat, but the setup has now been in service for around thirty years of full time live aboard usage with no mishaps.

I have lots better things to worry about than this setup!

Jim