A320
In the Fcom you'll only find thatSome of the fuel supplied to each engine goes from the high-pressure fuel line in that engine, through the integrated drive generator (IDG) heat exchanger (where it absorbs heat), to the fuel return valve, and back to the wing tank.This is to serve cooling the IDG.
Recirculation of fuel to the fuel tanks according to the engine oil temperature, the fuel system configuration and the flight phase
In the old generation Aircraft like the B727 For example you had fuel heater switches.
Last edited by Johnman; 14th September 2007 at 00:03.