HW but no CH but it's not the 3way valve?

[ollski]

Simple way to check the programmer is to take the front off and link a bit of wire from permanent live to ch on.

 

[D_Hailsham]

When i turn on the CH the light comes on at the programmer but nowt happens.

I'll have a tinker with the voltage testing but not sure what i'm looking for.

You have been told what to check; but, to save you scrolling back, here are step by step instructions.
Post the results of your tests.

1. Check your wiring and that connections are done up
2. Turn off HW and CH and turn CH and HW stats down
3. Turn CH on and turn CH stat up until it clicks
4. Use voltage tester/meter to check the voltage on grey and white wires. It should be 240V on both.
5. Leave CH on and CH stat turned up.
6. Turn the HW on, leaving HW stat turned down and check grey and white wires. Should have 240v on both.
7. Turn the HW stat up until it clicks on, check grey and white wires. Should be 240V on white and Ov on grey

 

[SMILER2]

THANKYOU all whom helped me here.
I have tested the voltage and changed the junction box as a result and now have it all up and running!!!

CHEERS!!!!!!!!