Upon arrival, found house temperature below setpoint despite boiler cycling normally. Discovered partially closed valve on return side above pump causing restricted water flow, which led to system overheating and short cycling. Opened valve to restore proper circulation. Also identified plugged backflow preventer preventing system from automatically adding water when needed. Verified boiler (GL Series AWR105ENS72PSU, 105,000 BTU/hr input) is fully operational after adjustments.
Performed inspection on Lennox natural gas furnace that was unexpectedly shutting down. Diagnostic testing revealed a failed heat exchanger requiring system reset. Documented condition with photos showing internal component wear and attached appropriate warning tag. Recommended replacement estimates for both furnace and AC system.
Diagnosed IBC boiler/water heater system experiencing inconsistent domestic hot water supply. Identified undersized boiler unable to meet demand requirements, failing circulator pump on domestic water side producing noise, and need for mixing valve installation. Documented system parameters via control panel showing DHW-indirect load configuration with 121°F tank setpoint, and recommended replacement of both boiler and pump along with mixing valve installation to resolve temperature fluctuations.
Performed annual maintenance on 13-year-old furnace including filter replacement (16x20x1) and comprehensive tune-up. Diagnostic testing with dual port manometer showed pressure readings of 3.25/3.26. Replaced dirty filter to restore proper airflow and system efficiency.
