How to wire a Honeywell thermostat to a Worcester Boiler?

Having a bit of a quandary. I’ve picked up a Honeywell CMT927 programmable thermostat and I’m attempting to wire it up to a Worcester Bosch 24i Junior combi boiler. Now I’ve done my best to try figure it out myself and I think I’ve got my head around it. Here’s the wiring diagram I’ve drawn up:

Where can I get help wiring a Worcester Boiler?

Try Worcester technical help (link on their website), they are very helpful and will tell you the boiler’s needs.

Which is Honeywell wireless cylinder thermostat Pack 3?

Sundial RF² Pack 3 (Y9420S2005) contains: Wireless enabled programmer (ST9420C) Wireless room thermostat (DT92E) Wireless cylinder thermostat (CS92A) Ideal for adding a room thermostat and a cylinder thermostat to a traditional system. Features Energy saving TPI control Wireless enabled…

What does switched live mean on a Honeywell boiler?

B is ‘switched live’ to energise the boiler’s Live Return when the ‘stat is calling for heat. N.B. in the ‘stat L and L are already internally linked. Take the receiver supply from the boiler so that there is one point of isolation.

Try Worcester technical help (link on their website), they are very helpful and will tell you the boiler’s needs.