Chris "fixed" the part that 2 previous techs didn't/couldn't. According to Chris, the part that her was there to replace was not needed...the "old" part just needed to be plugged into the unit!! Thankfully, he didn't charge me for this call. However, I suffered through the coldest week of the winter because a part wasn't plugged in! So, I wonder...were the previous techs incompetent, or were they trying to sell me a part that I did not need?! Thank you Chris for getting me my heat back!