Thompson Plumbing, Heating & Air Conditioning came out to evaluate and diagnose 4 year old Rinnai tankless water heater with an error code 17. Performed a hard reset on unit to remove code and to regain hot water to residence. Called technical support and it’s recommended to remove, inspect and clean gas valve assembly. This will prevent error code 17 from reoccurring. In addition, a trap will need to be added to condensate line to prevent condensate from backing up and entering water heater. Justin would like to have yearly descale service performed at the same time of gas valve repair.