All about the money the tech fixed the thermocouple and told me that it was mandatory that I also get another part that was 350 but when he went to his truck and did not have the part, I suddenly would be ok without it. My system also needed to be bled and he was only interested in selling me big ticket item then bleeding. And turn out the tech fixed my problem incorrectly which created more issues and I had to get thermocouple and everything re done 6 weeks later. Of course they claimed it was not their fault but I had two certified have tech tell me whomever put the thermalco did it wrong and did some damage. Not happy