Hi chaps - after about 8 years using an Anton Sprint which was great but getting bit long in tooth , last week I bought a new Kane 455 kit - thing is the 3 boilers I have used it on since have all given high CO readings - 50 - 60 ppm and the only way I can get the CO reading to drop is by increasing the excess air thereby reducing the CO2 reading. This is the opposite of what I am used to- something not right here....