11-17-25 RTU #6 Install three frez-stats found bad on my last service call. Tested system in AC mode working at this time. RTU number six did a recheck on the right side heat exchanger found disabled and then when I checked it, I was getting high CO levels at 250ppm and climbing. Today I did a recheck on it. I cleaned the inducer motor wheel, that has some debris in it. However, my levels are still high around 190 to 200 ppm. Did speak to Lee explain what I found, theirs potentially if there is a crack up there as the unit heats up on a real cold day, the CO levels is gonna probably increase the best to replace it now along with the other heat exchanger.