Arrived on site customer stated that they are having intermittent hot water at their shower. Upon inspection opened cover to tankless and visually inspected for leaks did not find any. Next ran water at shower that was getting intermittent hot water while simultaneously check gpm flow at the tankless and it appears to be keeping up and not shutting down. Then ran another fixture and it is maintaining hot water. Found that the handle to the shower was stiff and usually indicates scale build up and that the cartridge is beginning to fail along with fluctuating temperatures. Gave options to get on the phone with ao smith tech support to verify that the tankless is not the issue but customer would like to just have the cartridge replaced. Replaced cartridge and tested all work and everything appears to be in working order and there is no fluctuations in temp at the shower. Collected payment
