A new mysterious random clicking that

bob b wrote:
is driving us crazy. It is like the sound of a solenoid but it will click once or twice or ten times randomly. At times we won't hear it for hours then it clicks for half a day. It seems to be from the board that controls the Hydro-Hot but touching all the parts to feel the exact location is inconclusive. The one clue is that the top green light on the right side is on while clicking but when it's off the clicking stops. Any ideas?