Chrysler Grand Voyager - Heater not heating - Johnnyd

Just bought a used Chrysler Grand Voyager (2006 model) - the Auxiliary Cabin Heater seems to be on all the time even when the engine heats up (apparently between 1/4 and 1/2 on the gauge is ok?). This is with the AC setting on Hi or set to 25-30 (70+). Even when the engine gets to 1/2 the 'blower' remains cold or fairly cold. Is this right? If not what should I suggest to the garage?