Flying the airplane in 35°F OAT yields a cabin air temp of around 75°F. Also, cool air or a mixture of heated and cool air can be adjusted with the existing heat control knob.
The installation was field approved using the existing installation on the C-180 as a basis. Heated air is taken from the left side muffler heat shroud. Cool air is taken from a 2" nozzle on the rear engine baffle. The C-180 heater divert valve was placed in the same general location as the old valve but had to have a patch on the firewall as the shape is different. Be sure to use stainless steel or equivalent for the patch, no aluminum.
The installation was straight forward once we figured out where everything was going to be placed.
The old heater valve was removed from the firewall.
The C-180 fresh air/heat diverter valve was mounted on the firewall. This is the only part that has to be found, everything else can be fabricated from sheet stock. Hose sizes were reduced from 3" to 2". If I did it again, I would retain the 3" hoses for better air flow.
The C-180 heater distribution duct was mounted on the back side of the firewall. This duct can be easily fabricated from sheet stock.
New side panels were fabricated with integral air ducts. As an option, the later style oval cross section heater side wall duct hoses with some sort of fabricated exhaust grill could be used with standard side panels if you don't want to fabricate new side panels with integral ducts.
