10/3/22- my heat did not turn on last night and it was cold here in Chicagoland. Before I called a technician and spend $150 I decided to check out my furnace myself. The furnace was completely dead and even the fan did not turn on. I checked for power and then found out it was blinking code 23 for "Pressure Switch Did Not Open". Then I noticed a pinched pressure tube has been pinched since initial installation 15 years ago.
