My house came with a Naoplean 1402 fireplace insert. The fan worked when I looked at the house, but wasn't working after I moved in. I imagine it's either the on/off fan speed swith, or the thermal switch that doesn't allow it to kick on till the fireplace heats up. How do I get this thing apart to check the motor out? I found a manual on line and it refers to removing two screws, but I don't see them.