The control system (see §10.5.6) should be performing
its function. Thermostats should be properly calibrated.
Time clocks, setback devices, and automatic controls
should be intact and operating. Bearings and belts
should be in good shape and belts should be tight. Bearings
and other moving parts should be properly lubricated
with the appropriate lubricant. Lubricant selection
can actually have a significant effect on system performance
and efficiency