My warm floor is not heating very good.  My question is:  What type of circuit breaker is required for this circuit? I am using a THQL15G circuit breaker. It was suggested that i use a THQL15HM, heavy magnetic circuit breaker for this application.  They are very expensive and before i purchase one i would like your opinion.  The problem is that my longest run is only 10 feet in length.  I have 2 runs that are about that length on separate connections at the transformer. Either run gets warm when they get to the end of the run.  The warmth over the entire floor is very spotty and it just does not feel right.  It is a new install and my pictures are on the way to your company.  I installed this exactly like the video on this site and insulated under the floor.  Any suggestions.