it takes about 15-20 minutes for me to reach work in my about 5 year old mazda6 and during this cold ,car will warm up inside to the right temperature only when i am about to reach office!!! i am guessing this is not normal or efficient enough. it has always been like this since i bought this car second hand last year. could anbybody help please. . what could be wrong with my ac? once it warms up there is no problem. its just that it is too slow to begin with.

 

not A/C, heater. the heater coil can be all gunked up with stuff. Ever have radiator flushed? Is there enough coolant in radiator? maybe thermostat ? What does temp gauge read? Is heater core feed hose and return hose hot to the touch?
Highway driving or city traffic driving? Start with system flush and refill , and proceed from there.