Help replacing heating thermostat please

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I have an old analogue thermostat that I want to replace with a digital programmable one. The old analogue one has three wires into it whereas the new one I've purchased only talks about connecting two wires, can this be done? I've added a few images which hopefully will help. The first is the connections on the old thermostat, the second is the wiring diagram from the cover of the old thermostat and the third is the wiring diagram from the new thermostat. It says to connect the boiler to the 'com' (common) and 'no' (normal open) terminals. Thanks in advance.
 
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One of those wires on the old thermostat is a nuetral. (Those old drayton thermostats needed a neutral to work). Your new thermostat doesnt need the neutral.

Just park the neutral wire in a connector block and use the other 2.

Ps. It seems they have used a blue wire as a live conductor in the old thermostat. It is fine to do this but it should be sleaved with brown sleaving. Make sure you sleave it when you replace the thermostat.
 
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Hi,

Thanks very much for your help! Quick question, although the new thermostat is a two wire one, it has a third terminal labelled 'nc' (normal closed), is this somewhere I could connect the neutral to... Or not...?

P.S. Am I right in thinking that on the new one, the common is the constant live and the 'no' (normal open) is the switched live?
 
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Hi,

Thanks very much for your help! Quick question, although the new thermostat is a two wire one, it has a third terminal labelled 'nc' (normal closed), is this somewhere I could connect the neutral to... Or not...?

No. Don't connect the neutral to anything. Park it in a connector block

Just use the 2 wires. Nc is not used in your case

Yes you are correct.

The wire that is live when the thermostat is not calling connects to 'com' (common)

The wire that becomes live when the thermostat is calling connects to 'no' (normally open)
 
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it has a third terminal labelled 'nc' (normal closed), is this somewhere I could connect the neutral to... Or not...?

NO that would create a short circuit Live to Neutral. The neutral must not connect to anything.

The neutral wire is the one at the left hand of the old stat ( the all silver terminal )
 
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