What percentage of a washing machine's energy is used purely to heat hot water?

MultiFuelBurner

Happy for others to take risks based on their own research and foot in past but we still use 40oC for the daily washes and 60oC for bedding and we do a monthly boil 90oC clean of the washing machine.

Overkill...maybe....bacteria free......yes.

Money saving should not decrease health imo.

The upshot of all this cost of living crisis (detest that term) is that some people have gone too far and may be putting themselves at risk with lack of heating, not heating hot water in invented system enough and washing bacteria ingested items at too cool a temperature to not kill them.

However as I said, read the links in this thread, do your own research and make.up.your own mind but don't let others just tell you 20-30oC is fine without the research. 

Sterlingtimes

Chrysalis said:

With something like the octopus mini you might be able to do the maths, watch the live read out as it spins, as it pumps, and so on.  To get an idea.

That is a very good idea. Thank you. I will get some screenshots from our current cold-fill Beko and will repeat when the mixed-fill Ebac machine arrives next week.

My first screenshot shows that most of the activity above baseline occurs in the first 20 minutes.

QrizB

I did a 40C wash-and-dry last night (we've got a basic Indesit washer-dryer). It used 3.12kWh, per my plugin ZigBee energy monitor.

I'm not sure if this helps the thread but it makes me feel like I'm contributing

Sterlingtimes

MultiFuelBurner said:

Happy for others to take risks based on their own research and foot in past but we still use 40oC for the daily washes and 60oC for bedding and we do a monthly boil 90oC clean of the washing machine.

I follow your drift. I would not be happy if I learned that an hotel in which I had been staying had been washing sheets and towels at 20 or 30 degrees. There must surely be a standard for hotels.

MattMattMattUK

MultiFuelBurner said:

Happy for others to take risks based on their own research and foot in past but we still use 40oC for the daily washes and 60oC for bedding and we do a monthly boil 90oC clean of the washing machine.

I would suggest that the solution is probably somewhere in the middle. I wash towels at 60, bedding at 40 and everything else at 20 or 30 depending on what it is. 

MultiFuelBurner said:

Overkill...maybe....bacteria free......yes.

Money saving should not decrease health imo.

The upshot of all this cost of living crisis (detest that term) is that some people have gone too far and may be putting themselves at risk with lack of heating, not heating hot water in invented system enough and washing bacteria ingested items at too cool a temperature to not kill them.

Generally it is not the heat that kills the bacteria on a 60c wash, generally bacteria do not begin to die from heat until it reaches 65c, ideally higher. The heat is there to help soften and break down the oils from skin and to help remove those, the washing product should then kill and remove the bacteria, something which has been shown to happen even on a cold wash with modern cleaning products. If your aim was to reliably kill bacteria with heat alone then you would need to be using the 90c long cycle.

MultiFuelBurner said:

However as I said, read the links in this thread, do your own research and make.up.your own mind but don't let others just tell you 20-30oC is fine without the research. 

By "do your own research" I hope you mean read other published, peer reviewed research? I am not sure many on here have the skill to process bacteria samples and then evaluate the results.

Ultimately though I think people have to do what they feel comfortable with and as it is not something that impacts the rest of us then it does not really matter what people do in the privacy of their own home. 

The_Green_Hornet

Maybe the best practice is simply to follow the washing instructions on the labels affixed to the items to be washed.

I don't know if they have been peer reviewed though

MultiFuelBurner

MattMattMattUK said:

MultiFuelBurner said:

Happy for others to take risks based on their own research and foot in past but we still use 40oC for the daily washes and 60oC for bedding and we do a monthly boil 90oC clean of the washing machine.

I would suggest that the solution is probably somewhere in the middle. I wash towels at 60, bedding at 40 and everything else at 20 or 30 depending on what it is. 

MultiFuelBurner said:

Overkill...maybe....bacteria free......yes.

Money saving should not decrease health imo.

The upshot of all this cost of living crisis (detest that term) is that some people have gone too far and may be putting themselves at risk with lack of heating, not heating hot water in invented system enough and washing bacteria ingested items at too cool a temperature to not kill them.

Generally it is not the heat that kills the bacteria on a 60c wash, generally bacteria do not begin to die from heat until it reaches 65c, ideally higher. The heat is there to help soften and break down the oils from skin and to help remove those, the washing product should then kill and remove the bacteria, something which has been shown to happen even on a cold wash with modern cleaning products. If your aim was to reliably kill bacteria with heat alone then you would need to be using the 90c long cycle.

MultiFuelBurner said:

However as I said, read the links in this thread, do your own research and make.up.your own mind but don't let others just tell you 20-30oC is fine without the research. 

By "do your own research" I hope you mean read other published, peer reviewed research? I am not sure many on here have the skill to process bacteria samples and then evaluate the results.

Ultimately though I think people have to do what they feel comfortable with and as it is not something that impacts the rest of us then it does not really matter what people do in the privacy of their own home. 

Lol yes I don't envisage anyone buying a chemistry set to analyse the results I do mean as you say published, peer reviewed research.

Although I am not saying don't buy a my first chemistry set 😂

BellaBlondykeTheThird

The_Green_Hornet said:

Maybe the best practice is simply to follow the washing instructions on the labels affixed to the items to be washed.

I don't know if they have been peer reviewed though

I don't think anyone should peer review what goes on in my teenagers bedsheets they just get the 60oC cotton 3 hour 30 minute treatment 😂😂

Alnat1

Maybe I'm missing something that needs careful explaining to me but will say it again, why do people feel the need to wash towels at a higher temperature than their clothes?

Your towel is used to dry your clean body after a shower/bath, it doesn't really get "dirty". You then put on your underpants, that you are happy to wash at 20/30/40C even though they were in contact with the not so clean bits of your body for many hours prior to washing.

So what was the point of the hot washed towel? To stay cleaner for an extra 2 minutes?

booneruk

Alnat1 said:

Maybe I'm missing something that needs careful explaining to me but will say it again, why do people feel the need to wash towels at a higher temperature than their clothes?

I know this isn't adding much to the discussion, but I wash everything at 30c, have done for years and I'm still alive to tell the tale!