Have HVAC Questions? Ask an HVAC Expert for Answers
Welcome to Just Answer, my name is ***** ***** I will do my best to help you with your issue. If my initial response doesn’t answer your question then let me know and we can continue our conversation.
Generally inadequate voltage to the HSI is due to a bad connection or a bad board. Check the HSI voltage back at the board. If you still get 90 vac then you probably need a new board assuming you have 120 vac to the unit.