When I enter the "installer/configuration" menu, I get vC which can be changed from 5 to 95. Only the left and right arrows are displayed (I don't get the up and down ones.

Page 4 of the manual makes the programming look easy but I don't seem to get what it says I should get...

Press Menu
Press and Hold "installer config" for 5 seconds
Use up and down arrows to select reference number (<--- I don't get these so I can't select the various item numbers)
Use left and right arrows to select options

Any thoughts?

I have a two stage AC and two stage gas furnace.