Poor communication, stated that they would return the next day to fix part, no one showed up, after several phone calls we were told that the part hadn't even been ordered. When the part was ordered it was the incorrect part. I constantly had to call and follow up when they would be returning. This company had contracts with reliance, I had a specific plan with reliance and stated that I did not want this company back into my home. Unfortunately there was no other available service engineers so if I wanted hot water I had no choice. After approx 4 weeks I had hot water. I informed dons heating and cooling that I would not be paying the bill for the inconvenience and that Reliance would be covering it, only to receive phone calls and final notices of bill payment. Dons heating and cooling would not listen to me the customer when I informed them that Reliance were covering the bill. Dons heating and cooling ,the customer is always right !!! You need to remember that. Never again would I use your service or recommend this company.