Plumbing Questions? Ask a Plumber and Get Answers ASAP.
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.
Could be a partially blocked vent. Could also be due to kinked vacuum tubing or water in the tubing to the draft pressure switch. Could also be a failing switch.