roof heat coils

[american spirit]

i just moved into a new ranch home. the previous owner put up heat coils on his roof. the roof does not have much slope as with most ranch houses. i was thinking one of the following

1. there is a insulation/ ventilation issue and he was getting ice dams in the winter

2. he used the coils to melt snow just to get the snow off faster to decrease the load of heavy snow on the roof.

3. the guy was just old school and there is no problem.

i always thought heat coils meant roof issues. any recommendations. i might want to add that i have a cathedral ceiling where the coils are. there may or may not be insulation up there. likely R-13 if there is, as the rest of the house was done with that.