If the water heater and the heating had been working, this would have been a reasonable place to stay. However, to offer a place in the winter in London with a faulty boiler and therefore no heating or hot water is not acceptable.
The indoor temperature was less than 10 degrees Celsius during the night. A cold shower in the morning with the water at near freezing was not an option.
Until this problem is fixed, the property should not be offered to anyone else.