Tankless heater and HE washer

[Turbow]

Hey guys. So a friend of mine has a Bosch tankless water heater. Not completely sure of it's age as he moved into his home 4 or 5 years ago and it was already there. About 3 years ago he bought a Samsung HE washer (top loader) and dryer set. He said everything was fine until about 3 months ago the washing machine stopped getting hot. I went over to check it out tonight to see if I could fix it. We took apart the water heater and cleaned the heat transfer setup of all the soot and ash and other normal crap you get from burning propane. He's a bit out of town by the way. The washer and dryer are on opposite ends of the house, about 80 feet from each other. He says the hot water was never an issue before and that it used to steam the glass lid of the washer. He's in an earth contact home with a second level and his water lines run between floors. There is a utility sink in the laundry room but it doesn't get very warm. There isn't a flow regulator in that faucet so maybe it flows too fast for that? Every other faucet in the house gets hot no problem. Even in the bathroom right above the laundry room. Any thoughts?

 

[Mr_David]

I'm not an appliance expert but try turning off the cold water valve to the washer and see what happens. or maybe even to the faucet.
maybe the solenoid valve in the machine is casing a cross over or the faucet at the sink.

does the system have a recirculating hot water line?