What is your hot water temperature?

throwaway4372

throwaway4372

throwaway4372

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I'm working through a problem with my home hot water temperature, and came across two facts:
a) 60 °C is recommended on the cylinder thermostat to kill legionella
b) 43-49 °C is the recommended maximum tap temperature (varies because e.g. thin skin on old people scalds easier)

These facts aren't compatible with each other (you can either have legionella or get scalded!).

So I wonder how people reconcile it... survey time!

What is your hot water temperature?
Tap: max tap water temp in °C
Cylinder: temp on cylinder thermostat in °C
 
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I think I set it to 47C the other day. I was finding 45C didn't quite deliver what I wanted to the taps.

The reality is that taps contain an anti-scalding device, so you wouldn't ever get 60C out of them.

I don't have a cylinder though.
 
I don't have a cylinder, but i have the combi set to 55c for HW.

The tap recommendation is a tad dumb tbh, use a mixer.
 
50-55c. Waste of gas going any higher. We cycle through the water quick enough to not have to worry about legionella. Technically anything above 50c is fine for legionella, but 60c kills it within minutes.

Also don't need to worry about legionella if you do not have a hot water cylinder.
 
jaybee said:
Can you talk us through that statement?
Click to expand...

"To prevent scalding, the temperature of hot water discharged from, or to, any bath or bidet should not exceed 48oC. Where hot and cold water are supplied to a fitting, this may be achieved by use of a thermostatic mixing valve (TMV) or fitting. Such valves or fittings should comply with BS EN 1111 or BS EN 1287."
OK, I was 3 degrees out.
 
I went into an onsen once at 44c, it was HOT when it is a body of water at that temperature and you sit in it...but I like it cooler, much cooler than that...probably like high 30's.
 
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dirtychinchilla said:
The reality is that taps contain an anti-scalding device, so you wouldn't ever get 60C out of them.
Click to expand...
Temper that..........rarely and only if specifically fitted. And generally only thermostatic mixer taps for showers/shower bars - and if you have a mixer tap, you are already half way there.
 
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dirtychinchilla said:
"To prevent scalding, the temperature of hot water discharged from, or to, any bath or bidet should not exceed 48oC. Where hot and cold water are supplied to a fitting, this may be achieved by use of a thermostatic mixing valve (TMV) or fitting. Such valves or fittings should comply with BS EN 1111 or BS EN 1287."
OK, I was 3 degrees out.
Click to expand...
Most taps do not have TMVs. They're usually only fitted to showers.
 
Yeah I just don't get that statement. "Taps have anti scalding devices so don't worry". No they don't. Some do, most don't.
 
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Raymond Lin said:
I went into an onsen once at 44c, it was HOT when it is a body of water at that temperature and you sit in it...but I like it cooler, much cooler than that...probably like high 30's.
Click to expand...

People have different sensitivities and preferences to heat, that's for sure.

I need to bathe in the 40s for it to feel nice, high 30s feels lukewarm after a few minutes.
 
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mattyg said:
We have them fitted at my restaurants.. Because of stupid street.
Click to expand...

Usually fitted in schools too and for the same reason.

Regarding the OP, I had a fault on the system (hot water zone valve was always open and the wood burning boiler kept feeding it) where the hot water temperature reached 85C. No Legionnaires living in that tank!

Normally the hot water tank is set to 55C to 60C and the tap is set to just about the point where I can't stand it no more.
 
300L hot water cylinder at 45C with a weekly cycle to kill off any legionella. It automatically kicks in to reheat when it reaches 40C.

I find even when it reports the temperature is down to 40-41C in the tank, I still get a pleasant shower.
 
55dC on a 300L tank, playing it safe. Timer is set to heat the tank from gas boiler for 1 hour each morning only. Don't run out with just two people and prevents boiler cycling. Occasionally press +1 hour on the control if guests are staying and showering too.
 
No hot water here. We only have electric heating for water, and it's simply too expensive to run every day. Use a kettle to boil water if we need any.
 
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