Washing Machines with Hot Fill

At first impression, it would seem that if you are lucky enough to have a sustainable source of ‘on tap’ hot water available, it might make sense to have a hot fill washing machine.  A sustainable source of hot water would come from sources such as solar panels or geo-thermals, which are becoming more and more achievable for many people.  

This source of hot water is an excellent source of renewable energy for home use, showers, baths etc. but when it comes to using this hot water to fill your washing machine is when the problems arise.


  • Most hot water storage tanks are generally as high up in the building as possible, this is to give you the best water flow.  Unfortunately, the downside of this is that it can take the water a very long time from tank to machine, thus losing the temperature of the water.  Try running a hot water tap in the kitchen for instance, and see how long the tap needs to be open before the water is too hot to leave your hand under the tap. 
  • Flow levels for hot water are slightly slower than for cold mains water, which increases the time from tank to machine even further.
  • There will be a lot of water standing in the pipes and hoses from the hot water tank to machine, resulting in a much lower fill temperature than desired.
  • Even if your tank is closer to the machine, the time taken to draw water from the tank into the machine will mean that the temperature of the machine will become much too cool for the purpose.
  • All pipes and hoses will need to be lagged in accordance with local regulations, to reduce the loss of heat on the journey from tank to machine.

Before you think about moving to a hot fill machine, it is well worth your time carrying out in-depth research first.  It would be very disappointing to purchase a machine with a hot fill capability as, at the present time, it is not possible to deliver hot water to the machine at the required temperature levels.

You may be surprised to learn that it is very difficult to purchase a hot fill machine in the UK at the current time.  There may be one or two available, but believe the costs would be extremely high and would not give you the results you require.

Obviously manufacturers are working hard to resolve this dilemma, as many people would like to reduce both the costs of running a normal cold fill washing machine, and to reduce the environmental impact of heating the water in the first place.

Renewable sources of hot water are certainly on the increase, and many new properties have to offer greater improvements on environmental issues, such as solar power and geo thermals as mentioned above.

You may also be aware that buildings designed for multi-occupancy, such as apartment blocks, will provide a communal hot water holding tank for the use of all residents.

With all this progress in buildings, it will not be too long before washing machine manufacturers will catch up with demand and provide machines that are capable to work within the temperature range provided by a hot water fill method.  This will also hold true for dishwashers as well, hopefully in the not too distant future.








Disclaimer: The information provided has been prepared as a guide only and the steps taken are likely to vary for different appliance models. We strongly recommend using a qualified engineer to undertake major repairs and fault finding.


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