Bob and Tim are discussing the job that they are about to start. They are at a residence and the system has a blown low-voltage fuse. Tim said, “Let’s just change the fuse and try it and see if the system will start up. The only thing it can do is blow another fuse."
Bob said, “I think there is a better way. Fuses do not blow for no reason, it means there must be some problem in the low-voltage control circuit. I think we should shut the control voltage off and see what the Ohm readings are in the low-voltage circuit. The fuse is blowing during the cooling cycle so it stands to reason that we probably have a problem in the cooling circuit."