When I was an electronic tech many years ago I repaired circuit boards some companies especially Honeywell had no part number only factory assembly line number they did not want anyone to repair their circuit boards Honeywell was so greedy they want you to buy another $1500 circuit board that was only worth $50 they know you can not buy repair parts from anyone else. I tested good parts before they went bad then trial & error I found replacements that worked. Then we went on a mission to make sure other factories had part number for maintenance repairs. Then the company I worked for went on a mission to haul all Honeywell equipment to the scrap metal yard then replace all Honeywell equipment with another companies equipment. The company I worked for had about 2000 factories in the USA they made many unrelated products each line of products had a different company name,. Once I showed my boss how much money could be saved in our maintenance repair cost but other over priced items still could not be replaced Honeywell could hold us at ransom buy our parts at our prices or your equipment will not make parts the company I worked for started trashing all Honeywell equipment. Example, Honeywell was selling 50 cent micro switches for $150 each. I called Microswitch company and talked to engineering department I was told Honeywell buys microswitches made with no part numbers it is listed as priority part made special just for Honeywell. That made the board of directors so mad they ordered all Honeywell equipment replaced in all there factories. LOL I have been retired 15 years I never hear about Honeywell these days I wonder of those sneaky snakes are still in business. HOME electrical appliance / piece of equipment, are not made to be repaired these days.