My husband and I recently purchased the HVAC shutoff system from Ken at Kadtronix, and we couldn’t be happier and more impressed with the system and also with the service we received from Ken. We bought the system for a new vacation rental condo on the beach in the Cayman Islands and as the cost of power in Cayman is so high we were really concerned that we may incur high utility bills due to renters leaving doors and windows open when the air conditioning system was running. Ken was fantastic and was happy to speak with us when we had questions regarding installation and since we had the system installed it has worked extremely well. We would highly recommend the system and Kadtronix.