honeywell st699 to honeywell st9400c
- Thread starter dbull
- Start date
D
Deleted member 267285
I think you have the hot water off in the wrong terminal, try the blue wire in terminal 2 and put it in terminal 1.
- Joined
- 28 Oct 2025
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Hi, All I am replacing below ST699 (currently connected with Thermostat and Kingfisher Potterton Gravity boiler) with ST9400C . Need some help with Wiring Diagram.
Currently
There is a loop between 5 & 6 >> This need to be discarded ?
From L there is loop to 6 >> Should I use feed from L to connect to 3(in ST9400C) ?
While swapping:
ST699 - ST9400C
L - L
N - N
3 - 4
6 - 3
7 - 1
8 - What should I do with this ?
Any help would be much appreciated.
Currently
There is a loop between 5 & 6 >> This need to be discarded ?
From L there is loop to 6 >> Should I use feed from L to connect to 3(in ST9400C) ?
While swapping:
ST699 - ST9400C
L - L
N - N
3 - 4
6 - 3
7 - 1
8 - What should I do with this ?
Any help would be much appreciated.
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