Manhattan’s remaining oil plants cluster in older pre-war buildings that never converted — Washington Heights, Harlem, Inwood, and parts of the Upper East and West Sides hold the most — typically large cast-iron sectional boilers with power burners, running steam or hot-water distribution. Newer construction and most large post-war buildings are gas, so the triage treats an oil call as likely-older equipment by default.
Older oil plants have older controls and burners: cad-cell flame eyes clouded with age, electrodes worn out of spec, fuel lines and filters overdue. Parts for common commercial burners are still standard stock — have the burner brand and model from the rating plate ready and the parts question is usually settled on the call. If the plant burns gas, the gas boiler page covers those fault families.