We?ve talked about a second NACA vent on the 8s for hot days, but what have others done to get heat to the rear seat on cold days? A 4 hour trip from Houston to Colorado this winter left us both (but especially Diana) in pretty cold air. We have heated seats but that doesn?t do much for the face, hands, and feet.
In an attempt to get heat to the back seat I set up our system like this:
Air is heated through a muff on the #3 exhaust and controlled with a valve at the firewall. Air from the NACA vent on the fuselage is also controlled with a valve just off the vent. Downstream of both vents is a ?Y? to mix the two streams, followed by another ?Y? to split the air between the two vents on the panel. My thinking was that the heated air would make it to the back seat better if it came through the vents, rather than being dumped in the cockpit at the firewall. I also thought that the setup would allow for mixing fresh air with the heated air to regulate the temperature, but all that did was allow COLD air to leak past the butterfly valve to mix with the COOL air from the heat muff.
Have others found that one heat muff isn?t enough and added a second in series? Once you have HOT air available to the cabin, do you dump it at the firewall or try to route it further back? Any other suggestions? Paul, what is your setup and how did it work at FL210?
In an attempt to get heat to the back seat I set up our system like this:
Air is heated through a muff on the #3 exhaust and controlled with a valve at the firewall. Air from the NACA vent on the fuselage is also controlled with a valve just off the vent. Downstream of both vents is a ?Y? to mix the two streams, followed by another ?Y? to split the air between the two vents on the panel. My thinking was that the heated air would make it to the back seat better if it came through the vents, rather than being dumped in the cockpit at the firewall. I also thought that the setup would allow for mixing fresh air with the heated air to regulate the temperature, but all that did was allow COLD air to leak past the butterfly valve to mix with the COOL air from the heat muff.
Have others found that one heat muff isn?t enough and added a second in series? Once you have HOT air available to the cabin, do you dump it at the firewall or try to route it further back? Any other suggestions? Paul, what is your setup and how did it work at FL210?
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