This is because hot water quickly cools in the pipework and often takes a while to run hot.
Do modern washing machines need hot water supply. Not as long as you dont use the warm or hot water temp selection switch on the machine. Once this is done you have finished plumbing the water supply for your washing machine. Some washing machines require both hot and cold water supplies other washing machines and almost all dishwashers need just a cold water supply.
The manufacturer says that Oxi-Clean works best in warm to hot water so when youre washing with cold water first dissolve Oxi-Clean in 16 ounces of warm-to-hot water then add to the cold water. Your immersion heater or boiler will heat up hot water which is stored in a tank. If your HW is heated by gas solar or some other fuel appreciably cheaper than electricity.
If you are doing colors rags or pet beds using hot water is a waste of energy and could shrink or color run the items. This is a very common myth. Its quite common for kitchen combi boilers to have hot water reservoirs and to be in kitchens close to a washing machine location.
Do the same for the cold water hoses. However because modern washing machines use very little water and it takes so long for most peoples hot water to actually run hot it needs a sophisticated washing machine to utilise it properly in all the different circumstances at peoples homes. Modern washing machines dishwashers and electric showers take cold water and heat it themselves so you dont need a supply of hot water waiting for them in the tank.
So in cases where the water is supplied from a hot water tank or with a long pipe-run from the boiler a hot water valve would hardly fetch in any hot water. Just be sure to mix with a little cold water beforehand ensuring that your water isnt too hot. Older and newer simple washers in the USA have a connection to hot and cold water supply and no way to heat water.
Modern washing machines dishwashers and electric showers take cold water and heat it themselves so you dont need a supply of hot water waiting for them in the tank. Scotsman 27 Mar 2007. But in fact you really dont need to be heating your water all the time.