That characteristic smell is due to mold re-infestation, when you start to turn on the AC and it comes within 30-60 seconds, and it goes away 5-10 mins away. Same for the car AC.
This is a common issue.
Different pax have different reactions to this.
Your chemical wash done was not sufficient/in depth. I suspect that chemical wash was done with alkaline coil cleaner too. (I was recommending solvent/detergent based cleaners, which are actually milder than the alkaline coil cleaner).
That means you'd need chemical overhaul where the tech would dismantle the coil and every part of the FCU, use alkaline coil cleaner to whack all the parts thoroughly coz everything is exposed, and then flush the caustic alkaline coil cleaner away which is only possible coz everything is exposed. Else any alkaline coil cleaner is left unflushed, those copper pipes and aluminum evaporator coil fins are gonna react and be corroded over time, leading to slow and chronic gas leaks (really $$$ issue). So do engage a proper contactor if you wanna do this, cannot skimp on the cost one.
Also, since the evaporator coil is dismounted, there is always this accidental gas leak risk coz the copper refrigerant pipes are disconnected and reconnected after every time. You cannot do this chemical overhaul too many times, it's too risky and the risk goes up with lousy AC techs who does a lemon job.
Or you need a service provider that can do a very proper and thorough job with solvent/detergent cleaners + regular basis (preferably with high pressure water).
There are vendors offering chemical wash as low as $55, and there are those who charges $90.
And General servicing for $20.
No prizes for guessing.
Learn to DIY lah, with the proper tools and cleaners. Need some small investment in this as well, cannot escape one. Either that or you pay for the services, good ones from good service providers.
Guys! You all got DIY clean your aircon blower ?
https://forums.hardwarezone.com.sg/...diy-clean-your-aircon-blower-5091470-221.html
