There could be several reasons why. You need a proper analysis to determine the reason. I'd suggest you have a system performance test done on your AC system.
The 2001 Honda Odyssey has a V6 engine.
The 2001 Honda Odyssey has 24 valves.
The 2001 Honda Odyssey is a gas-powered vehicle.
The 2001 Honda Odyssey has a 4-speed automatic.
The 2001 Honda Odyssey's turning circle is 37.7 ft..
The height of the 2001 Honda Odyssey is 5 ft. 8.5 in. (68.5 in.).
The 2001 Honda Odyssey is 16 ft. 9.2 in. (201.2 in.) long.
The 2001 Honda Odyssey has single overhead cam (SOHC).
The 2001 Honda Odyssey has 67 in. of rear hip room.
The 2001 Honda Odyssey has 64.5 in. of rear shoulder room.
The 2001 Honda Odyssey has 62.6 in. of front shoulder room.
The 2001 Honda Odyssey has 40 in. of rear head room.