Quote Originally Posted by Gary L View Post
And exactly where is that allowance, in the ITCS?
Well, along the same vein where in the ITCS is the allowance for a cool suit?

As for the heater:

Ducting may be added to provide fresh air to the driver/
passenger compartment. This ducting shall be located in the
driver and/or passenger window area, with no modifications
to the bodywork. Only the cooling duct is permitted in the
window area. It is not permitted to otherwise fill in the window
area. The complete duct assembly in the plane of the window
shall be no larger than 100 square inches.
I suppose you could argue that your duct comes in feeds a heater/blower and it is delivering air to the driver/passenger compartment.