Solved

Washer Connected To Hot Water In Error

PEpete64004
Asked about 11 years ago 7,542 views
0

Hi

My washine machine only needs cold water connected to it to work. It heats the cold water up to the required temperature.

For the last 3 years it has been connected to hot water straight from the boiler. Every time it draws water it uses 75 degree water from the gas boiler.

Can anyone estimate how much this has cost per load on average and how much it should cost per load if it uses only cold water.

I'm trying to claim from the landlord.

Thanks

Solution Summary

AI-generated from this discussion

This thread was marked as solved. Here's a summary of the problem and the fix, generated from the discussion below.

Cold-fill washing machine connected to hot water supply in error

The problem
The washing machine was designed for a cold-water connection only but had apparently been connected to the hot supply for about three years. The poster wanted an estimate of the extra running cost per load in order to pursue the landlord.
Likely cause
Misconnection of the appliance to the hot water supply. The accepted reply said any cost difference would depend on the machine's water usage, the programmes used, the type of hot water system, and changing gas/electricity prices, so no reliable figure could be calculated from the information given.
What fixed it
No repair procedure was discussed. The accepted advice was that the additional cost was likely impossible to work out accurately without detailed usage and energy-cost data. It was also suggested to double-check whether the quoted 75°C was actually the domestic hot water setting, as it might have been the central-heating temperature instead.
Checks to try
  • Confirmed the machine only required a cold-water connection
  • Check the actual hot water temperature
  • Check whether the boiler setting quoted was for hot water or central heating
  • Consider whether the property had a combi boiler or a hot water cylinder

Safety: The discussion noted that domestic hot water much above 60°C is dangerous and wasteful.

Cause identifiedGenerated 10 Aug 2026 · AI summaries can make mistakes — read the full thread below.
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6 Answers

Accepted Answer
0
WH
WhitegoodshelpVerified Engineer
Answered about 11 years ago

Wow, that would crease a lot of laundy badly – never mind the wasted energy. An interesting problem that's likely to be impossible to work out. You'd need to know exactly how much water the washing machine uses on a full cycle, what programmes it's been used on and how much it has cost in gas or electricity to heat (say) each litre of water up over the 3 years as energy prices have fluctuated so much. It also depends on if you have a combi boiler that heats up water as it's drawn off, or a hot water cylinder that stores a tank full of hot water.

I would guess it's the latter because if you had a combi boiler heating up to 75 degrees all the time water was drawn it would be rinsing your laundy in boiling hot water and that would have ruined many items and at the very least caused them to be severely creased. I can't imagine anyone putting up with that for 3 years.

Also, hot water should be set at 60 degrees. Any higher is a waste because you are heating up water so hot it's dangerous and almost unusable without cooling it down with cold water (eg. to wash your hands or the posts) So you are just heating it up to cool it back down. Turning it down to 60 will save a fair bit of money.

Having said that, I would double-check the temperature, as 75 degrees could be for the central heating. Most boilers should have separate temperature settings for water and heating. Hot water is normally set at about 65 on the boiler.

Whitegoods Help — appliance repair expert and forum host.
0
AN
andyr12345
Answered over 9 years ago

do you remember one washing machine manufacturer years back as a selling point was that it rinsed in hot water, was it hoover or someone I cannot remember now. I dont think it took off - I doubt if it was anywhere near 60c though of hot water on the rinse but they claimed it rinsed better than cold water and killed bacteria, but you need at least 60c to kill bacteria and germs dont you? - and i wonder if the clothes came out creased because they were rinsing in hot water? - also I though the whole idea of rinsing in cold water is that it gets rid of the suds? - if you added hot water that would just create more suds wouldnt it?

0
WH
WhitegoodshelpVerified Engineer
Answered over 9 years ago

I've known dishwashers rinse in hot water. But not washing machines. The only way a washing machine could utilise hot water for rinsing would be for it to mix the hot water with cold water after determining and monitoring the temperature of the incoming water. This would be an extremely expensive thing to do. There has been debate on some of my articles about cold water only washing machines where some people expressed a desire for them to rinse with warm water to which I gave the same reply. It may well be that rinsing in warm water might be beneficial but to be able to do it technically is complicated and expensive. It would add quite a lot of cost to the price of a washing machine. I doubt that any benefits would be worth it. Rinsing in hot water directly would badly crease and damage some laundry.

Whitegoods Help — appliance repair expert and forum host.
0
AN
andyr12345
Answered over 9 years ago

Ive often wondered Andy why washing machines cannot utilise the heater that are used in Dishwashers

to heat the water coming into the washing machine drum , rather than the element immersed in water at the bottom of the tub like they have done for years? - if the dishwasher element was placed just after the cold water inlet valves before the soap dispenser then hot/warm water could flow into soap drawer dissolving powder/tablets better, keeping drawer cleaner and pipe from dispenser to tub hose cleaner and putting hot/warm water straight into the drum surely cutting down on time to heat up water in the drum?

- whats your view on this, and would it really cost the manufacturers much more than the element at the bottom of the drum? - or maybe the 2 elements could be used in conjunction to shorten down the amount of time to heat up the water in the drum

1
WH
WhitegoodshelpVerified Engineer
Answered over 9 years ago

Hi. It would be difficult to fit such a bulky element near the dispenser. There's little room in modern washing machines for anything new, especially large drum capacity ones. Also for it to instantly heat all water passing through it then it would need to be pretty powerful.

Time spent heating up the water isn't an issue. Biological detergents in particular apparently work most effectively when starting in cold water and gently heating up. Also time is an essential component of the wash calculation. Laundry is washed by mechanical action combined with water and detergent. The detergent needs time to work. So introducing water already at the desired temperature wouldn't really save much time. The laundry would still need to agitate the laundry back and forth for a good while to properly get clean.

Also, the heater inside the sump hose of the dishwasher isn't fitted there to heat water quicker. It's just there because it's cheaper than the large ones usually fitted in the base of the dishwasher. It works on a dishwasher because all water is constantly recirculated through the sump hose heater and back into the dishwasher. If a similar system was to be used in a washing machine they would have to have a recirculation pump fitted.

Whitegoods Help — appliance repair expert and forum host.
0
AN
andyr12345
Answered over 9 years ago

That would be a good Idea then I think, fit recirculation system to a washing machine. Fit the dishwasher heater near to the drain pump and sump hose at the bottom of the machine and instead of using a special recirculating pump fit a diverter valve with a synchronous motor on it so that when the machine is washing it diverts the water back into the top of the drum and when it needs to empty motor opens up the valve for the other port leading to the drain hose. - mind you I think there are already machines out there that use recurculating systems , but I dont think they have an inline heater to warm the water up.

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