I called them and was not satisfied with their answers. They will not replace anything until it fails…I was discussing preventing failures by replacing old components likely to be on their way out and typically replaced in these units such as filter caps, switching panel bulbs to led units, power relay etc. They will not do that. Its like driving a car with worn out tires and refusing to replace them until you have a failure or an accident and they want a $120 fee just to look at it. I found another option and he said he agreed with everything I was planning to do plus no diag fee.