I purchased an XRay unit from a company in SLO ($31,000) which has never worked consistently. I need legal help. What type lawyer/legal issue is this?

I'm not certain if this is a business law issue or some other category, but I would like to return the faulty equipment for refund or at least full credit (although I would rather not work with this company. I was told by a local company that this brand of panel is notorious for problems. I have everything documented. They are in San Luis Obispo and I am in West Palm Beach, FL.