Defected Product, and no response on complaints..

Location/place: geeta colony,delhi

Name of company/service: voltas, TATA

I purchased a 1.5 ton vertis air-conditioner from M/S Anisha T.V. corner ,Main Parwana Road, new delhi on 06/07/2011.From the very beginning the said unit has been performing below par and repeated complaints were made to their autorised repairer and customer care.The gas of the compressor unit has been changed thrice already and there is still defect and the whole AC unit needs to be replaced. The matter was also reported to voltas people vide complaint nos.
11jl0904004 dated 09 july 2011,
11jl2003478 dated 20 july 2011,
12mr0203197 dated 02 mar 2012, 12my1008950 dated 10 may 2012,
12ju0200217 dated 02 jun 2012, 12ju1201027 dated 12 jun 2012, 12ju1604444 dated 16 jun 2012, 12ju1703133 dated.17 jun 2012. I have also taken the matter with voltas vide my mail dated
12 august 2011,
02 jun 2012,
12 jun 2012. The matter is still unattended by them till date.Despite having spent a huge amt.Of saving to have some solace from severe heat I continue to be tormented by heat as the a/C is lying idle.I have lost faith in the Voltas and now requesting refund of the cost so as to enable me purchase a new a/C of proven capability