Unit heater 1 Model number: LF24-250A-5 Serial number: 5613E01258 Ran gas leak detector over all gas joints on system found no gas leaks. Checked flue pipe and heat exchanger no holes or cracks system is functioning properly at this time. Unit heater 2 Model number: LF25-250A-1 Serial number: 5619K10305 Ran gas leak detector over all gas joints on system found no gas leaks. Checked flue pipe and heat exchanger no holes or cracks system is functioning properly at this time. Unit heater 3 Model number: LF24-250A-5 Serial number: 5613E01259 Ran gas leak detector over all gas joints on system found no gas leaks. Checked flue pipe and heat exchanger no holes or cracks system is functioning properly at this time