Responded to a service call for a Rheem hybrid water heater that had disabled itself and was reported to be emitting a burnt odor. Upon arrival, line voltage was verified at the unit, and the system was checked for stored or cleared error codes. Proper voltage was confirmed to both heating elements. A full visual inspection of all wiring was performed, with no signs of burnt, damaged, or shorted connections found. All thermistors were tested and confirmed to be operating within proper specifications. Rheem technical support was contacted to review findings and testing results. Based on confirmed diagnostics, Rheem determined there is an internal fault within the control board that cannot be visually inspected or field-tested. Rheem is shipping a replacement control board directly to the customer. A return visit will be required to install the new control board once it arrives. The system was installed in July 2025, and all work and parts are covered under manufacturer warranty.
