The tech measures the broken spring - wire diameter, coil length, and inside diameter - rather than assuming it matches the door's age, since a 1978-built house in Aztec may already carry a non-original spring from an earlier repair. He checks the drums, cables, and center bearing plate at the same time, because on hardware this old a spring failure sometimes isn't an isolated event.
Once the new spring is sized and installed, the door gets balanced by hand - lifted to waist height and checked that it holds position - before the opener is reconnected, since an unbalanced door puts the same strain back on a new spring that broke the old one.
Across the roughly 2,409 households on this side of the service area, most of these jobs are straightforward single or double spring swaps. We'll tell you plainly if what we find during the job is bigger than that, rather than installing a spring and leaving a worn bearing plate to fail next winter.