I have a friend that has a Winston Pellet Stove. She has had it for 3 years. She has regularly cleaned it and all of a sudden it has stopped working. Any information on this type of stove. The model # is WP-18 Design # WP-18D1. It also has a number of WP-24 on it. The stove was manufactured in Chino, CA the date of Mfg. was 9-90 and the serial # is: 4090. Thank-you for any information on this stove.