kW/ton is the one number that tells you whether a chiller is doing its job or quietly burning extra electricity every hour it runs. A centrifugal chiller fresh off commissioning might sit near 0.55 kW/ton. Two years of fouled tubes and drifted setpoints later, that same machine can creep toward 0.8 kW/ton without a single alarm firing. Sign up to start trending kW/ton against baseline and catch that drift while it's still cheap to fix.
kW/ton is simply electrical power input divided by cooling output. Lower is better, and it needs no unit conversion to compare across chiller types. A rising trend over weeks or months is one of the clearest early warnings a chiller plant gives before capacity problems or a compressor failure shows up.
Benchmark Ranges By Chiller Type
Around 0.8 kW/ton is a commonly used caution line for a centrifugal chiller. Below its expected range, fine. Above it and holding, that's the signal to schedule an inspection before the drift compounds further.
OxMaint logs kW/ton against your chiller's own baseline every time it's checked, and flags the unit the moment it drifts past its threshold, long before a full efficiency audit would catch it. Sign up for a free trial to start trending your chiller fleet, or book a demo to see deviation alerts set up for your plant.
Trending It Right Takes A Few Extra Steps
Fouled condenser tubes, low refrigerant charge, and negative subcooling are the most common causes of a rising kW/ton trend. None of these throw a hard alarm on their own. They show up first as a gradual climb in the metric, which is exactly why a one-time snapshot reading misses them and a running trend catches them.
From Trend Line To Work Order
Frequently Asked Questions
Catch Chiller Drift Before It Costs You
OxMaint tracks kW/ton against each chiller's own baseline, corrects for load and condenser temperature, and triggers a work order automatically when performance drifts past threshold. Sign up for a free trial to start trending your chiller efficiency, or book a demo to see it mapped to your own plant.
