Found this aircon installation company over the web last Oct. They were shortlisted as one of the competitively priced vendor. Engaged Mr. Ang of Harvest Aire, and requested him to include all my stated requirements about size of copper pipes, brand n size of insulations, electrical cable size in the purchase order. Unlike other vendors that I contacted, there was no demand for extra charge to meet those requirements.
I postponed my installation by slightly over 1 month without being pestered too.
The installation workers were both humble Malaysians--easy to communicate when routing the pipes. Mr. Ang was responsive to calls and messages when there were questions.
Feeling glad that I engaged Harvest Aire, especially when my neighbor complains about water droplets found on the surface of his trunking because his contractor convinced him that there will not be any problem to use thinner insulations. He is contemplating to dismantle his false wall to change the insulations n trunking now.
it is worth to be KS to use at least 1/2" Armaflex insulations if trunking is concealed.