Replacing a Honeywell T40 thermostat with a Honeywell DT90e

[JackStraw123]

Hi
I'm replacing my old dial thermostat with a digital
The wires going in from left to right are
Earth
Blue
2x Black
Brown

When electrically tested none are live with thermostat off

Research on this and other sites suggest
2x Black into B
Brown into A
Tie off and isolate Green/Yellow and Blue

Is this correct?
My hesitation is the fact that I have 2x Black and not one

Many thanks

 

[ShaunCorbs]

Make safe neutral eg blue, make safe earth eg green and yellow

1 from old into a on new
3 from old into b on new

 

[JackStraw123]

Make safe neutral eg blue, make safe earth eg green and yellow

1 from old into a on new
3 from old into b on new

Many thanks. followed your advice and works perfectly
Really appreciated, will make a donation to charity by way of thanks
Cheers