Responded for a call on no heat. When I arrived by test the furnace in heating mode. Flame ignition was not starting due to a pressure hose. Going from one pressure switch to the other that was not seated correctly. It most likely came loose from the vibration of the blower motor. I then replaced one of the square pressure hoses in the inducer motor. It looked as if it had been pinched because it was at an awkward twisted angle. I then cleaned the last two hoses going from the inducer to the collector box and the pressure switch to the gas valve to make sure there are no obstructions. I then tested the heater three times to make sure it started up correctly.