Preventive maintenance is the easiest line item in a facilities budget to hollow out, because a visit that achieves nothing looks identical on the invoice to a visit that catches a failing compressor.
The difference is what gets written down. A visit that produces numbers can be compared to the last one; a visit that produces a tick cannot.
The minimum useful record
- Suction and discharge pressure, with ambient noted alongside them
- Superheat and subcooling, not just "gas OK"
- Compressor running current against the rated figure
- Condenser and evaporator condition before and after cleaning
- Oil level and condition, and the date of the last change
- Any alarm history since the previous visit
None of these take long. Together they turn a maintenance contract into a trend line, and a trend line is what lets us tell a client that a unit will need attention next quarter rather than next weekend.
A tick tells you someone attended. A number tells you what changed.
