In a working household, hot water isn't optional. In a rental, it's also a call from a tenant who needs an answer. A tankless that starts throwing codes puts the owner, the tenant and sometimes a property manager on the same problem at once.
Most of the time the cause is ordinary. National City's water is hard, and scale builds up in the heat exchanger until the unit starts shutting down. Sometimes it's an ignition part or a sensor. Either way, it's findable.
Someone comes out, finds the cause and gives a straight answer on repair or replacement. Whoever's on the other end of the call gets the same clear answer, and the owner makes the decision.
