LG Charged Extra for Using Old Pipes Instead of New Ones

I ordered a brand-new air conditioner from LG Turkey, which was delivered and installed in June. Instead of using the new installation pipes provided with the unit, the installers used the old pipes left by the previous tenant. In early August, the unit started blowing hot air. I requested service under warranty, and they took the unit for inspection. Now, they're asking me for ₺2,500 in installation fees because they used the old pipes instead of the new ones provided. I was never informed of this, nor was a solution offered for not using the new pipes. I experienced a similar issue with V** and received a replacement unit within two days. LG seems uninterested in standing behind their product or addressing customer issues. I’ve filed a complaint with the Consumer Arbitration Board and my lawyer.