Henry. Just a quick note to say thank you for the work you carried out on my roof. I have since been up and inspected the installation as you suggested and could no problems. I was astounded at the professionalism you and David displayed while you were here. Joan and I couldnt believe the time you took for the removal, installation and plumbing modifications you both carried out. We are both very appreciative and the system is working really well. It is a welcome change to have a reliable hot water system. Thanks once again to you both.