Keep in mind that many vintage Euro/UK front loading washing machines, especially those with manual timers held heating cycles based on time not temp.
Wash cycle could last much longer than necessary if the set temperature was reached but one waited for the timer to advance based upon whatever parameters the machine used.
My vintage Miele W1070 (W700 in Europe)allows a certian amount of time for heating water, regardless of incoming temperature being 40C or 70C. Of course the thermostat will click off the heater once desired temp is reached, but the timer will not advance until it is supposed to. OTHO if the wash temp is not reached and it is time for the timer to move, it will click on, however the heating will continue, and indeed goes on until the proper temp is reached. Though have a hunch once it starts getting near the end of the cycle thermostat will shut off regardless, though am not sure.
Running on 22V, and decent Euro front loader should bring "cold" tap water from a house in Sweden in winter to temp rather quickly.