On demand gas hot water

[William_H]

Here in west oz any gas hot water heater must be flued if it is indoors. Even outdoors my heater is considered illegal because it is too close to an opening window. I sealed the window. So I would never consider an unflued heater inside a boat. My newest heater has fan ventilated electric ignition and computer controlled temperature but I would not think it any more efficient than the old one. (except not having continuous burning pilot light) I believe you can get battery electric ignition on some water heaters. But essentially I reckon Neeves should stick with what he has. Proving you can get plumbing apart (corrosion can be a problem) you can get spares. ol'will

 

[coopec]

Unflued gas heaters have been banned in Australia.

Unflued gas heaters produce a number of pollutants as a result of combustion. Pollutants that can harm your health include nitrogen dioxide and carbon monoxide. Unflued gas heaters also produce water vapour that can indirectly affect health by increasing the growth of moulds and dust mites.

https://www.worksafe.act.gov.au/health-and-safety-portal/safety-alerts/unflued-gas-heaters-and-your-health

 

[Kelpie]

Our boat came with a Morco Paloma gas water heater. Similar principle to a domestic boiler but much smaller. It could have been flued but ours was just on the bulkhead beside the companionway.
I wasn't a massive fan of it, tbh. To do the usual boaty shower where you turn the water on and off in short bursts, you'd end up with a slug of cold water in the pipe which was pretty unpleasant. It worked well if you left it running, but who has the tanks and gas to do that??

It's now removed because I valued the extra space more.

 

[Neeves]

Our boat came with a Morco Paloma gas water heater. Similar principle to a domestic boiler but much smaller. It could have been flued but ours was just on the bulkhead beside the companionway.
I wasn't a massive fan of it, tbh. To do the usual boaty shower where you turn the water on and off in short bursts, you'd end up with a slug of cold water in the pipe which was pretty unpleasant. It worked well if you left it running, but who has the tanks and gas to do that??

It's now removed because I valued the extra space more.

We have a bucket in the shower cubicle and collect the cold fresh water before the hot water arrives from the boiler - it is used to wash the dishes.

In terms of gas - a 9kg cylinder last months and more months (with 2 x 2 showers per day and all the cooking). We only worry about when the gas will run out - mainly because the last time we filled the cylinder is lost in the mists of time.

The critical resource is fresh water - but we have a de-sal unit and learnt to be frugal - Navy showers. Navy showers are not the bracing exercise I recall in the UK where air temperature can be 'chilly' - it is more pleasant here.


As I've mentioned in the past its the 21st Century - surely we don't need to sacrifice improvements in lifestyle over the last 50 years and return to the 1950s?

Jonathan

 

[Kelpie]

We have a bucket in the shower cubicle and collect the cold fresh water before the hot water arrives from the boiler - it is used to wash the dishes.

Do you run the shower continuously? And if not, do you find that there is a small delay in the burner kicking in, resulting in a little bit of cold water each time?

 

[Neeves]

Do you run the shower continuously? And if not, do you find that there is a small delay in the burner kicking in, resulting in a little bit of cold water each time?

No, run tap and collect cold water. When hot water arrives, wet down. Switch off shower, soap, switch on shower (water stays hot in pipes) rinse off. If there are two of you in the shower (ours takes 2 in comfort) it takes longer to soap down and maybe the water is cooler - but there are too many distractions to worry.

There is a very slight delay in the burner kicking in but its not something that we notice as an issue.

Our boiler has a 2m run from boiler to shower, we use those press in plastic plumbing pipes and fittings (the name of which I forget, red for hot and cold for blue).

Currently our seawater temps, Sydney, are around 24 degrees and our water tanks are in the bilges. In Tasmania the sea water temp can be 16 degrees and we do notice that 'hot' in Sydney needs more cold to make it comfortable than in Tassie. We thus use less water in Tassie as we 'waste' more in Sydney - if that makes any sense.

I note, now, there are many stand alone 'boilers' sold to the caravan/camping market with integral pumps. You hang them up, connect the gas pipe to a cylinder. They don't use flues as they are intended to be used outdoors or in a free standing external shower cubicle. You could use them in an internal shower cubicle - but you would need to lug a cylinder inside the caravan/motor home - which would be a distinct disadvantage. I have not yet looked in detail but I suspect that the water usage (the volume of hot water produced) will be less than from a boiler designed for use in a house/flat - but this might be a good thing as it will use less water. I also have not checked how the gas is lit - our domestic unit has a pilot light (which we turn off religiously after every batch of showers (partially because it uses gas - which is effectively wasted if you don't need hot water). These devices would suit hanging from the boom on a yacht, close to the cylinder and having an appropriate water connector (swap cylinder gas pipes, connect to water pipe) and could be used under a cockpit tent or tarp tent over the boom (privacy).

If you are at anchor for a few days you will quickly use the hot water from the calorifier - this is one answer (or run engine to charge batteries and heat water).

More options than I thought but different compromises. Hot showers get a big thumbs up from the female crew (and I confess to being a bit of a wimp, or sybarite, and enjoy a hot shower at the end of a long passage). The young ladies soon learn they have enjoyed the shower too much as the skipper gets grumpy at the excess water usage.

There is no reason not to embrace the 21st century and have 2 showers a day.

Jonathan

 

[Kelpie]

We only ever used the gas water heater whilst in the UK. It was pretty unpleasant thanks to the delay. Long uninsulated pipe runs. I don't know if the Morco was particularly bad compared to other options.
We found showering aboard in the UK left the heads damp for a long time afterwards- no heater outlet in there.

Solved the problem by sailing further south. Now use a solar shower as much as possible, fed from rainwater which we collect from the solar panels. If it's too windy to be pleasant in the cockpit we'll shower in the heads, fed from the tanks, but have no method of heating it and really feel no need to anyway.

In an ideal world I suppose we would have a watermaker, generator, and calorifier, but these things were out of budget and we'd rather cruise on a simple boat than still be at work saving up.

 

[Neeves]

In an ideal world I suppose we would have a watermaker, generator, and calorifier, but these things were out of budget and we'd rather cruise on a simple boat than still be at work saving up.

Very, very true

You are living the dream - many only dream.

Jonathan