This was mentioned already but it is very unusual for commercial air conditioning equpment to not have time delays on the compressors. These are used because a compressor has a very difficult time starting under pressure and a unit needs time for pressures to equalize before a restart.
Line monitors are not as common but if the equipment was sensitive to the inrush currents associated with power outages, the HVAC company should have had the foresight to install those too.
Someone playing with the thermostat or a momentary power outage would cause a condition where a compressor would stop and try to start again under pressure. this "short-cycling" can burn up compressors.
And if you did cause a momentary (fraction of a second) high voltage condition due to in-rush currents, the heavy windings in the compressors would have handled it fine. It's the microwaves, fire alarm cirucits, computers, PA system, and other solid state devices that would have failed first.
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