Well.... Way back when I worked at the Exxon oil refinery, I ran the Sulphur Recovery Plant section which had a triple pass heat exchanger on two separate processor plants. The flow of each triple pass heat exchanger was set to enter the vessels in sequence in order to get the maximum exchange of heat between the counter-flowing vapors. The "in sequence" flow pattern worked perfectly well for taking the temperature down in stages, each exchanger dropped the temperature by more than 40 degrees. However, this required that each vessel have a flow controller valve installed upstream to prevent overheating inside the vessel. In the event of reactor overheating or excessive pressure in the pipeway, the vapors would bypass the exchanger and go directly to the effluent stack to be burnt and avoid burning down the heat exchangers or melting the tubes inside the vessels. Should this be a problem for us to worry about? Is there a chance that Macintosh will provide a safety system to divert the excess heat through an external cooler system? If so, who will come to your location to install it? Will private owners have to have additional plumbing installed in their homes? Etc, etc, etc? This subject is fraught with technical questions and should be discussed over a pitcher of beer and an extra large combo pizza. Who wants to be the host?