Our Landlord totally refurbished our bathroom 4 years ago. He also installed a shower fed by the combi boiler over our bath. This is now faulty and he is refusing to replace. He states that his responsibilty ends with making sure the boiler is maintained in legal goodworking order and that hot water is supplied to bath and sinks for washing etc. He then said if we chose to shower than we should payfor its repair as it is for our convenience. Is he legaaly responsible for its repair