Chrysler Repair: 99 Town & Country: Heat is inadequate, maill address, heater hoses

Question
Hello Roland.  I have a '99 T & C LXI whose heater comes on and blows lukewarm air for a while, and then blows coldish.  After shutting the heater off for a length of time, it may blow lukewarm air again when turned on, but only temporarily.  It takes about 5 minutes for the engine to warm up (1/2 on the tempature gauge).  The upper left radiator hose gets hot when the engine warms up.
I've replaced the thermostat and the water pump.  I've also flushed the radiator fluid, which was very dirty with a lot of crud-like mud.  The mechanic states that the heating coil needs to be replaced.   I appreciate your time and expertise.

Answer
Hi Edwin
After running the car for long enough to thoroughly warm the coolant and the heater core and the temp gauge is stabilized, then feel the incoming and outgoing heater hoses at the firewall on the engine compartment side. If they are similarly warm then the flow through the core is adequate and the problem is with the blend air door or the electrical feedback thereof. On the otherhand, if one hose is hot and the other quite a bit cooler then the flow is obstructed and then I would suggest back flushing the core by disconnecting the hoses on the fire wall side and running a garden hose flush of water backwards thru the core to see if you can improve the flowthrough. If the hoses are similarly hot, then there is a self-diagnostic capability that you should invoke to try and get a handle on what is wrong with the blend air door. It might be resolved by this procedure that also re-calibrates the feedback control, or it might suggest that the door is not moving or that its actuator is not working properly. The procedure is sufficiently long that I can most efficiently share it with you by xerox and postal mail of the pages. I can do this at minimal costs so you needn't reimburse me.
So check the hose temps and if those are ok get back to me with a postal maill address.
Roland