O General Air Conditioner — Split AC 1.5 Ton

It's been a year that i bought split AC 1.5 ton from Bercos. but experience has been horrible. in the sencod season of its operations, we can find ice on the coil at the setting of 22 degree celsius. Water drips from the indoor unit. on complaining to O general they say that since installation was not done by O general hence warranty is void. While I paid rupees 3500/- (against normal installation chantages of 1500/-), New bercos (dealer and seller) did not issue me any invoice for the same. While i was never told of installation by O general professionals was the option, now O general is contesting that it was lapse on my part and product is not covered under warranty.