Help compatibility and wiring for danfoss ts715 to nest thermostat combi boiler

[Steven Paterson]

Hi I'm looking for help to see if my existing system can be changed to a nest thermostat and how would I wire it up to the nest danfoss ts715 and RET2001M thanks

 

[Deleted member 267285]

Yes Nest would be compatible. The heat link would go in place of programmer and thermostat would be wired to the 2 wires on the Danfoss thermostat end, utilising T1 and T2. Disconnecting unused wires.

 

[Steven Paterson]

Hi thanks for your reply would any of these pictures be the right wiring type 1st or 2nd or 3rd if I had to guess I would say picture 3 is correct way but am not too sure thanks

 

[Deleted member 267285]

None of them, also it appears that your wiring is using terminal 3 as a spare?

L - L
N - N
1 (Com) to 2 on Nest
4 on Danfoss to 3 on Nest

T1 and T2 will possibly be the 3 terminal on Danfoss. Need to trace wiring to see if it corresponds at the other end.

 

[ianmcd]

If using T1 and T2 to power the nest thermostat you will also require an earth

 

[Steven Paterson]

Right the 3 is connecting to the thermostat at the other end witch is ON the grey with the blue sleeve is neutral I think this would go into T2 as it directly connects to neutral on the thermostat at the other end so would that mean one of the black wires with brown sleeve particularly the one coming from terminal 3 on thermostat would go into T1 and the other one not used would that be correct also I think the live going into the thermostat is coming from a switch neon that turns the boiler off/on but the neutron is directly linked with the programer ts715 Thanks

 

[Deleted member 267285]

No, no neutrals go to T1 or T2 - these are only for thermostat wires.

 

[Steven Paterson]

So what if I do
L - L
N - N
1 (Com) to 2 on Nest
4 on Danfoss to 3 on Nest
Earth to Earth Next to T1 T2
Then just disregard 3 on Danfoss blank them off then run a new 2 core wire form T1 T2 to thermostat T1 T2 and blank off all other wires at thermostat end would that work thanks

Read more: https://www.diynot.com/diy/threads/...thermostat-combi-boiler.586350/#ixzz7KIJnaGDT

 

[Deleted member 267285]

Link isn’t working, but seems like you’ve finally got it

 

[Steven Paterson]

Thanks for help got there in the end