Upgrade Honeywell ST9400 to T6R-HW

7 Nov 2019
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United Kingdom
Hope someone can point me in the right direction.
I have a Honeywell ST9400 with remote thermostat. The ST9400 is in the airing cupboard whilst the thermostat wireless receiver is in the loft next to the boiler.
When I replace these units with the T6R should I
1) replace the ST9400 with the T6R and then remove the wireless receiver and jump the connections; or
2) remove the ST9400 and wire the T6R-HW in where the current receiver is?
Hope that makes sense and I bet you can guess the next questions
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Remove the ST9400 and the wireless receiver. Use the cable that connected ther ST9400C to connect the Heat Link. You may need to go into the wiring centre to relocate the brown wire from your CH zone valve onto the Honeywell CH switch Live
I'm going to show my ignorance now, apologies in advance! I don't know why, but I feel I'm missing out by not having a smart thermostat. I have a Vaillant ecotec plus 418 heat only boiler. Sealed system with unvented hot water. Controlling that is a Honeywell ST9400C and a DT90E room thermostat. What benefits would I get if I upgraded to a TR6-HW kit. My programmer is in the airing cupboard so I have to go to that every time I want to override the heating/hot water. Could all those functions be done from the room thermostat or even my phone? I see that the TR6 is a smart thermostat. What would happen if, for example, my internet went down? Any other benefits? I'll have to 'sell' it to the wife lol.
thats The same as I have currently. I am moving to the T6R-HW mainly to set different temperatures at different times of the day. For instance I like it cooler in the morning and warmer in the evening. Plus there is the added advantage of being able to use the phone to control the settings and turn on and off etc. I think the T6R is better than the tado, nest, hive etc in one respect. If broadband or WiFi is down then those smart systems need to be controlled manually. The TR6 will work just not with the phone.
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Muggles, thanks for your reply. I assume you mean option 1) I can locate the T6R where the ST9400 is and use the current wires there. Then the Change in the wiring centre. I only have the following wired in the ST9400
1 - HW OFF
2 - CH OFF - nothing connected
3 - HW ON
4 - CH ON

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