The fan on the vent blower inside the ducane furnace sounds like it has water in it and won't get to full speed. The furnace won't ignite (light blinks 3 times to tell me pressure switch won't open) and it waits 5 minutes and then tries to run the fan again. Is there supposed to be a water sound inside the inducer fan?

No, shouldn`t have e water in it
Is it a new install?
Possible the drain lines from the exhast vent isn`t installed correctly,, if its new install u may want to call back and look over the drainage lines

Thank you. I took the fan off and drained the water out. I also found a crimp in the drain line. The furnace is working well now.