Preventive maintenance (PM)

What is preventive maintenance (PM)?

Preventive maintenance (PM) is scheduled service that keeps equipment working and heads off breakdowns. Federal O&M guidance from Pacific Northwest National Laboratory defines it as actions on a time- or run-based schedule that detect, preclude or mitigate degradation, with the aim of extending useful life. Changing filters and belts, cleaning coils, testing controls and lubricating motors are typical PM tasks.

Why it matters to a revenue leader

PM is the product most commercial services agreements are built on, and it carries a sales logic. Customers buy it to avoid failures and protect equipment life. Sellers use it to secure site access, a record of equipment condition, and a natural place to recommend repairs and replacements. In commercial HVAC, ASHRAE/ACCA Standard 180 sets minimum inspection and maintenance requirements, which helps sellers define a credible scope. A revenue leader should watch how much PM renews and how much of it turns into follow-on work.

A mechanical contractor sells quarterly PM on 18 rooftop units at an office park. On the second visit the technician records a failing economizer and two units past expected life. The seller turns those notes into a repair quote and a two-year replacement plan aligned to the owner's capital budget.