怎样做聪明的消费者（五）购买家电商品，要当面通电试机，并索取售货凭证和保修单。购买电视机要参加联合保修，一旦出现故障和其它质量问题，便于修、换、退。对于空调器，生产厂家一般都规定免费安装，有的随机附有“免费安装卡”，由销售单位或特约维修单位负责免费安... How to be a smart consumer (e) purchase of home appliances products, electric machine to face test, and obtain sales vouchers and warranty. To buy a TV to participate in the joint warranty, in the event of failure and other quality problems, easy repair, change, retreat. For air conditioners, manufacturers generally require free installation, and some random attach a “free installation card”, by the sales unit or special maintenance unit is responsible for free security ...