Damaged goods

I bought a radiator from silverton radiators in Trichardt Mpumalanga on02/10/2017.After fitting the radiator it was leaking and i took it back.They dont want to refund it and send it away to their h/office because they said it was not their problem but the problem was for H/office.The owner of the shop said that i musnt phone him again but ask my lawyer to phone him.I already bought another one and just want my money back.I will never recommend this business to anyone i know