Replacing Honeywell T6360b with T4 in underfloor heating system

[Amuia]

This is going to be a slightly long-winded explanation, but I'm trying to give as much detail as possible - thanks in advance to anyone who manages to read the whole thing..!

The house we moved into recently has underfloor heating on the ground floor. The bedrooms each have a Honeywell T6360b thermostat. This underfloor heating is one zone/channel on the main heating programmer which is a Horstmann ChannelPlus H47XL (this zone is set to constant "on"). The en-suite bathrooms have separate programmable controls (Aube TH132).

I'd like to be able to have the underfloor heating switch off at night in the bedroom, while remaining on low in the bathrooms. I can easily program the Aube thermostats to do this, but if I set the heating to switch off at night via the main Horstmann control then the Aube thermostats also lose power completely. (I understand why this happens, although it seems a bit of an odd decision..!)

To achieve what I want, is it as simple as replacing each existing T6360b with a Honeywell T4? (without any complex re-wiring etc?)

I've added photos of the relevant bits:
Existing thermostats (Honeywell & Aube)
Underfloor heating manifold
Main system controller

Please let me know if I'm missing any vital info, and thanks!

 

[stem]

I would guess that where the AUBE's have been installed now, there would have originally just been standard thermostats. Then the programmer would have provided the on / off control to the thermostats, that then in turn would control the temperature.

The AUBE's I suspect were installed later in the place of the thermostats, and as you figured, they need a permanent power supply, so presently the programmer has to be left permanently 'on' to provide this. However this shouldn't be a problem as the AUBE's are programmable thermostats and capable of controlling both heating times and temperature. Therefore they are designed to be powered permanently and a programmer isn't required. Quite often when a system has been modified and a existing programmer is retained, it is set to be permanently 'on' in order to achieve exactly the same thing.

The Honeywell thermostat wires are:

1=Live
2=Neutral
3=Switched Live
E=Earth


The T4 connections are:

A=Live
B= Switched Live

Therefore, the neutral wire is not required and should be insulated / isolated and tucked out of the way.
I believe that the T4 is double insulated and doesn't need an earth connection either.

 

[Amuia]

Many thanks for the quick reply That all makes sense, and confirms what I was hoping/suspected. I'll try a T4 and see how it goes!