If the transformer wires are shorted together, this will burn up the transformer. Normally transformers on the LV side (24 volt) are not grounded, but the solenoids that they control could be grounded, and a t-stat wire that is unintentionally grounded could burn up the transformer, but its not likely.
Answers & Comments
If the transformer wires are shorted together, this will burn up the transformer. Normally transformers on the LV side (24 volt) are not grounded, but the solenoids that they control could be grounded, and a t-stat wire that is unintentionally grounded could burn up the transformer, but its not likely.