Customer reported insufficient hot water during showers, requiring frequent adjustment of the temperature to maintain heat. Upon inspection, verified hot water temperature at multiple fixtures: • Kitchen sink: 120°F • Bathroom faucet (ran for over 30 minutes): maintained 120°F • Downstairs tub: 120°F Confirmed that the boiler fired properly when the indirect water heater called for heat. Also verified that operating a heating zone simultaneously did not affect domestic hot water supply. Noted that the indirect water heater does not have an expansion tank — installation is highly recommended. All components of the boiler and indirect water heater are functioning properly at this time. Based on findings, the next step is to have a licensed plumber inspect and diagnose the shower mixing valve, as this is the likely source of the issue. Customer also reported experiencing a sewer odor from the kitchen sink approximately once a month, which should be evaluated by a plumber as well.
