When the control switch to blower was being installed the power was not off and the wire touched one of of the leads to the milivolt control wire. Now the burner control swich does not work on the fireplace any longer. The thermopile seems to have shorted (there is a hole burned in the front side of the thermopile generator facing away from the pilot flame that I believe is result of the short circuit). How do I know if it's just the thermopile or the whole control unit that needs replacing?