Responded to no-heat call for an aging oil furnace in barn office. Diagnosed intermittent ignition failure; manipulated primary control which resolved the issue temporarily. System eventually fired up and cycled properly through multiple thermostat tests. Inspection revealed severely rusted flue pipe with significant holes due to environmental exposure. Heat exchanger appeared intact without visible cracks. Recommended replacement of primary control, complete oil tune-up service, and replacement of deteriorated flue pipe components.
