Believe product is hot water system that was comfortable and quiet P-CG series 7 that my father had installed. Notation on right side of unit is CP No 512404. Can you confirm that number is a P-CG (Series 7)? The system is cycling on and off every minute - gas on pump on - gas off then pump off and gas back on. What would cause this cycling? The water temp senser gauge is installed on the upstream outlet side above the boiler. Is this the correct location? What temperature should it be set at? Thank you for your help. Al Faenger 306 Grimsley Station Road St. Louis MO 324 846-9549