In 1996, design consultancy Priestman Goode launched an innovative new steel coil radiator, Hot Springs, onto the market. The product is now part of a permanent exhibition at the Philadelphia Museum of Modern Art. But it is also one of the best-selling radiators in the UK and Europe, and accounts for 10% of the company’s turnover. Does this make it art? Paul Priestman thinks so. While most designers are loath to call themselves artists, the founding Director of the award-winning company thinks there is something to be said for a product which is aesthetically pleasing on the one hand, and functional on the other.