Apart from the energy required to achieve and maintain that temperature there are legal requirements for domestic & commercial Hot Water Systems :
The Plumbing Code of Australia and relevant Australian Standards set strict temperature requirements for all hot water systems.
Plumbers must set storage temperatures to at least 60°C to control the growth of Legionella bacteria. For personal hygiene useslike showers and bathsthey must cap the delivery temperature at 50°C to prevent scalding.
In commercial settings such as kitchens, plumbers may set delivery temperatures higher, up to 70°C, for sanitary purposes.
Always include an approved tempering valve in new installations. Make sure that hot water doesnt exceed 50°C at outlets used for personal washing.
-- Edited by kgarnett on Thursday 26th of March 2026 05:18:28 PM
I have a Truma in my motorhome and it has the option of either 60 or 70 deg C.
I always make a point of rinsing the shampoo out of my hair first, just in case I run out.
I spent 3 months in Germany with my relatives. Their HWS is a heat pump system in the basement. It has 3 settings, 45, 50 & 55. They have it set on 45. The bathrooms are 2 floors above, never once was the hot water not hot enough. I always needed to add cold water. Ambient outside temperature was typically -5 to 0 degrees while I was there December to February.
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Procrastination, mankind's greatest labour saving device!
50L custom fuel rack 6x20W 100/20mppt 4x26Ah gel 28L super insulated fridge TPMS 3 ARB compressors heatsink fan cooled 4L tank aftercooler Air/water OCD cleaning 4 stage car acoustic insulation.
I learnt quite a few cold weather skills while there. I have been there many times before but only once in winter before briefly.
The central heating system is always left on level 1 at a minimum over winter so pipes don't freeze.
Once I tried to clean the car windscreen with water. It didn't matter how much water I put on the windscreen, it just all froze into solid ice. Which was actually impossible to scrape off.
If I had simply scraped it off initially with the windscreen ice scraping tool, it would have been easy, like I had done previously.
One lives & learns new skills in a cold environment. We were grateful that even though it was so cold, that we only had snow, but no rain! The rain freezes on the roads which turns them into a skating surface.
__________________
Procrastination, mankind's greatest labour saving device!
50L custom fuel rack 6x20W 100/20mppt 4x26Ah gel 28L super insulated fridge TPMS 3 ARB compressors heatsink fan cooled 4L tank aftercooler Air/water OCD cleaning 4 stage car acoustic insulation.
I Have done this ...and with common sense works well...just remove the tempering valve. The HWS has a thermostat set at 65 degrees so all the fearmongering about getting scalded is just that. The upside to this is that less hot is used in the shower and 2 people can have two decent but shortish showers without running out of hot.
Find out how to do it ...enough info on the net...but is a simple easy job.
Cheers Keith
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Nuthin is ever the same once I have owned it ......
