Fitting a Honeywell DT92E -Help please!

[D_Hailsham]

You have three wires at the moment and need three for the new stat.

NO! Four wires are required in this case as it is just a thermostat, not a programmable stat.

1. Permanent Live - Terminal L
2. Permanent Neutral - Terminal N
3. Switched Live from programmer CH ON - Terminal A
3. Switched Live to Boiler/Motorized valve - Terminal B

 

[dreadnoughtheating]

You have three wires at the moment and need three for the new stat.

NO! Four wires are required in this case as it is just a thermostat, not a programmable stat.

1. Permanent Live - Terminal L
2. Permanent Neutral - Terminal N
3. Switched Live from programmer CH ON - Terminal A
3. Switched Live to Boiler/Motorized valve - Terminal B

Yes, and as per my initial response, four core's. No Earth required. The receiver unit and hard wiring requirements are exactly the same whether its the DT92E or the CM 921/927 programmable stats. On Ideal Logics/Esprits (cheap appliances for even cheaper landlords) the switched core is required to go into a particular terminal on the block.

May I respectfully suggest that the OP looks again at the wiring diagram on the receiver unit's front cover (he/she has already posted a picture of it including the wiring diagram) and compares this with the requirements of the boiler.

DH