For this no heat call the customer's fuse at the air handler was popped, therefore preventing the system from running. Tried the number of different methods to include the hopscotch method jumping R to each individual call however I was not able to immediately replicate the low voltage short. I inspected all the low voltage wiring and found rubout of R on the gutter outside where the tstat wiring goes from the attic to condenser. I taped up the rubbed out area and insulated the wiring with electrical tape. System was heating and running upon departure. Customer would like to have a plumber Jerred to come look at their upstairs toilets, Wednesday April 9th early afternoon please. Customers would like a phone call before heading out 817-240-3229