Td5 temp barely gets above Blue zone

I recently had my thermostat, radiator and water pump replaced. Since then, engine temp sits just above Blue zone and heater gets luke warm at best. Any ideas where to start on this one?
Cheers

Definitely no air in the system? Or maybe coolant temp sensor?

Keycare said:

I recently had my thermostat, radiator and water pump replaced. Since then, engine temp sits just above Blue zone and heater gets luke warm at best. Any ideas where to start on this one?
Cheers

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Was it like that before everything got replaced? If it was ok then I would suspect a duff thermostat

Thanks for the quick reply.
What is the best way to check for air?

There was a period of a couple of months between thermostat replacement and then both rad and pump replaced together. Heating was normal after thermostat but I suppose that doesn't rule out duff thermostat. Stuck open?

Keycare said:

There was a period of a couple of months between thermostat replacement and then both rad and pump replaced together. Heating was normal after thermostat but I suppose that doesn't rule out duff thermostat. Stuck open?

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I would second the thermostat being the problem. It may not be stuck open, but may just opening early at the incorrect temperature. Testing it is easy enough, throw it in the kettle with the lid off and a thermometer and see what temp is at when it opens. Several people, myself included, have been through several new from the box stats until we found on which opened at the correct temperature.

The fact you say the heater is luke warm is a fairly sure way of telling the coolant is not getting up to temp - I would start it up and take it for a drive until the temp needle just starts to move up, keep driving it gently until the needle moves say another 1mm on the dial then pop the bonnet and feel the top radiator hose - it should be stone cold, if there is a hint of warmth to it then the stat has opened too early or is jammed open.

You should also be able to feel around the thermostat itself - if the bypass pipe (opposite main rad hose) is cool and the pipe that exists at a 45° angle is cool/warm and the top rad hose is warm then it sounds like it is jammed fully open and closed the bypass - no flow in the bypass from startup would be a big indicator of a jammed stat.

Good news is being an inline setup they are quite easy to change - buy OEM or genuine boxed - I don't know what it is about stats but aftermarket stats always seem to be junk!

I suspect by this point you have looked down the airlock issue, but if you have driven it, let it sit and driven it and the header tank is up to level then I suspect you don't.