2002 GCL -used When the heat is turned on to the lowest setting, "55" degrees, it blows the hottest air, same as if it were on high. At "lo" no heat, and at "55" maximum heat. Very occasionally, and randomly, it will work properly, with progressive heating as you turn the dial up, and only getting real hot as you approach "67" of "70"
but most of the time there is no adjusting it, only very hot air. As if there is something loose in a thermostat or something that blends cool and hot air. ????

2002 GCL -used When the heat is turned on to the lowest setting, "55" degrees, it blows the hottest air, same as if it were on high. At "lo" no heat, and at "55" maximum heat. Very occasionally, and randomly, it will work properly, with progressive heating as you turn the dial up, and only getting real hot as you approach "67" of "70"
but most of the time there is no adjusting it, only very hot air. As if there is something loose in a thermostat or something that blends cool and hot air. ????

I know this is an older post, but I had the same problem. It is likely the actuator, and I have to thank the members on this board for letting me know! Hope it hepls.