Defra-approved or/and Ecodesign stoves are designed and thoroughly tested before being allowed onto the market and every stove sold is identical. In the rare event a stove does not perform as well as expected it is always down to the installation, the chimney or circumstances unique to the property (pressure imbalances caused by local conditions, down drafts etc.). Here at Stovefitter's we have taken stoves back on a number of occasions for testing on our chimney and in every situation the stoves performed as expected (we may of course find a faulty stove one day but never as yet). We may, at our discretion, take a stove back once it has been used and in this situation a 50% refund would be provided (stove would be sold as second hand). We would, however, offer a 33% refund on a replacement stove.