I have an older (20 year old) A.O Smith 40gal Gas Water Htr. It has worked well but just stopped in last 24 hrs. I confirmed the pilot is on and stays lit but the main burner not working. I shut it down and relit pilot, the main burner came on but only for couple minutes. The exhaust fan is working fine. Wondering if the controller directly under the main control valve could be the cause. I think it is a Gas Pressure Sensor ? (It has 4 wires to it and specs include WR25M17 Type 702 PN 18039 24V, .35A , 1/2 PSI max). The reason I suspect this part is that the main burner comes on with slight movement of one of the wires at one of the 4 connection points on this part. Would love to have any thoughts on this.
WASHINGTON, DC–In cooperation with the U.S. Consumer Product Safety Commission (CPSC), A.O. Smith Water Products Company of Irving, TX, is voluntarily recalling and replacing approximately 29,000 flue baffles installed in water heaters manufactured and distributed by its McBee, SC facility between April 16, 1991 and July 9, 1991. The affected water heaters are limited to A.O. Smith natural and liquefied petroleum gas 30 and 40 gallon heaters. Only FSG and PGX models with serial numbers beginning with MD91, ME91, MF91, or MG91 are subject to this recall. A.O. Smith electric water heaters have no flue baffle and therefore are not subject to this recall.