ventilator ltv 950 not working. power is on completed post test.

Since this is a medical device, I think it will be hard to find information.

Based on your question, it is not getting feedback from the device that checks the vent and just hangs there. Similar to what Windows OS will do if it doesn't get feedback from a USB port.

Could be caused by a blockage. Any other cause is probably not user repairable.

you may have 2 situations, one can be select button is stuck and need to replace front panel, secondly check dip switch #5 to make sure it is off position (Switch toward outside ventilator). also #6&8 dip need to be off