Thanks for the reply.
I have my flight training at CAFUC,and my PA44 instructor is totally freshman on this airplane
,does not familiar with PA44...
I have POH,but I didn't find the answer..
1、I got it，loud and clear.
2、If the HTR OVER TEMP light is a cabin heater over temp indicator,why the color of it is red,I think red means the most important..Is cabin heater more important than VAC(it is yellow)
3、These two switches,I can switch them to left or right,the left of the upper one is SLV,the right is FREE;the lower one is CCW and CW