Hi Richard, have you tried feeling the heater hoses to see if they are hot? if not 2 things to check, water in the system, thermostat needs replacing as it is not opening, you say you have flushed out the rad! just to recap the proceed-er i would go about it,Fill the system up with winter summer antifreeze, start the car up with the heater blowing in the hot position on the dial's, let the car run untill the tep gauge reaches the center check & feel if there is heat coming through the pipes, I think with a new Thermostat you will have sorted out the problem.