Nest 3rd Gen and Baxi Platinum Combi 33

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12 May 2019
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So I fitted this yesterday and didn't get any heating - HW worked fine, open a tap and hot water, heatlink connected to thermostat by wifi and all leds ok. I followed this thread and wired exactly as shown - https://www.diynot.com/diy/threads/nest-gen-3-installation-with-baxi-combi-maxflow-wm-boiler.494416/
But no heating and no manual override when pressing the button on the heatlink. So looking at the Nest wiring diagram for 230v combi I noticed that there should also be a live into 2 on the heatlink so I added a jumper between L and 2, still nothing and yes all lights on heatlink ok - thermostat has been put on a stand in the lounge and said heating but nothing.

Lo and behold I wake up this morning and the heating is on! So now I'm a little bit concerned that I have cocked something up. When I had the boiler installed I opted for the digital programmer rather than the mechanical clock, I have no room thermostat only thermostatic valves on the radiator.

So questions are:
  • have I wired it correctly? (in the heatlink pic below the RH cable is L,N and E from supply side of terminal block on boiler and the 2nd cable is from terminals 1 and 2 as per thread mentioned previously)
  • is the digital programmer overriding the Nest? (I only entered the time after the power was off - no programs)
  • what temperature should I set the CH dial on the boiler for maximum efficiency or doesn't it matter?
[GALLERY=media, 102826]20190512_110929 by Max_max posted 12 May 2019 at 11:28 AM[/GALLERY]
[GALLERY=media, 102827]20190512_110944 by Max_max posted 12 May 2019 at 11:28 AM[/GALLERY]
[GALLERY=media, 102828]20190512_110950 by Max_max posted 12 May 2019 at 11:28 AM[/GALLERY]
 
The boilers internal timer should be set so that the heating is on 24/7 that will then allow the Nest take overall control.

The boilers radiator thermostat will control how hot the radiators get to the touch, and the Nest will switch the boiler on and off to maintain the room temperature set on the Nest thermostat. They are different thermostats and have different functions.
 
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