Supposed tech took one look at tankless water hear and said "It will cost more to fix than it is worth so I can sell you a new one for only $3000.00".
Called my 81 year old father who cleaned cobwebs off with broom and blew out area where overheat sensor is mounted. then he recycled control valve, lit pilot with unit mounted igniter, and then turned on hot water faucet in adjacent laundry tub.
Guess what??? It works fine. saved $3000.00 and you can too by not calling this outfit.