We've got a shiny new aircon system at work - they're replacing all the units in the entire building, including our one that was itself replaced at the start of the year - and yesterday they finished plumbing it in and turned it on. And consequently we spent the next couple of days trying to decipher the enigma that is the control system.
See, if you set it to 22°C and put it in auto mode, then it blows out cold air despite the room not being that hot. However if you set it to heat and drop the setpoint a few degrees it now blasts out hot air despite the room already being warm enough. Except for the unit in one of the meeting rooms which appears to do the opposite of whatever the main units are doing.
We half wondered if they'd miswired the temperature sensors and the controllers but this shouldn't be possible as there's actually a sensor in each controller (the previous building had a whole-building HVAC system that was indeed miswired, causing us to freeze a neighbouring office while trying to cool ours in summer). Or possibly having two units off of one controller (we've gone from one unit with part of the output ducted to the meeting rooms, to a total of four) is causing them to fight - again, this was an issue in the previous building where it tried really hard to maintain a 1°C differential across the room by blasting out very cold on one side and very hot on the other. Anyway there's someone coming in tomorrow/today to tell us about the system so maybe we'll get some answers.