Al, thanks for your reply, I may have made an error previously, just warmed car up and the thermostat works ok, also the silver valve is hot both sides, but the black one is cold both sides ? no flow, but..........I removed it and may have put in back to front, I have the black one with the flow coming out the heater back to the engine ? so do you think now with this is could be the valves ?...........the heater replacement does not sound good. thanks in advance
That's right, the black valve should be flowing from the heater back to the engine, this is the return pipe from the heater. (the valves have arrows on to indicate flow direction)
Try letting the engine cool down a little after a drive, (prob about half an hour, till the pipes feel cooler to the touch) then remove the pipes on the heater side of the valves, the water will prob be cold. then try removing the pipes on the engine side, these should both be warm water.
If this is the case then the valves are working and it's just your matrix that is at fault.
If the water in the return pipe after the bypass valve is cold, then you need to replace the valve aswell.
Make sure you get the valves the right way round before testing.
When the valves are out of the car try running the metal one under a hot tap with the flow going through the valve, (in direction arrowed on valve) if it comes out the other side of that valve then theres nothing wrong with it. If the water flows through to the black valve and exits that one then your valve is stuck and you need another one.
Test these things to make sure your valve is ok.
But i'm sorry to say it sounds like it's def your matrix!