EEVblog #1360 - REPAIR - Aircon Control Panel

[EEVblog]

Dave's lab aircon control panel has been dodgy for years, time to finally fix it!
A simple fault with rather interesting and complicated set of a symptoms based on a (poor?) design decision.

[CChin254]

IC Identification if y'all are interested in one image:

[tkamiya]

COOL/ELEC is for traditional air conditioner / resistive heating element setup.  Heatpump is more recent heating where flow of freon is reversed.

[jnissen]

The reason it went to run after you cycled it quickly is to allow the compressor in the AC to equalize pressure so it isn't trying to start under the high head pressure.  Standard to have delays if it short cycle ran for only a few seconds or minute or two. Protects the compressor from over current condition where you hear the thermal snap switch kick in and out!

[Kuber]

Just wondering if you checked the rest of the switches while you had it apart? 

[agtrbt]

Axial capacitors and inductors have gone extinct