Salus RT520TX Not triggering boiler

So it doesn’t come on with the Nest e?
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The heating comes on with the nest, but that is just for the rads upstairs, the underfloor heating is separate and all we have downstairs, and not coming on, I thought fixing the main thermostat might fix the problem, but it hasn’t.
Are the room thermostat’s set high enough? They maybe connected to a zone valve, check this if you know where to look for it.
Hi Ian, I’ve fitted the nest e, thanks for the recommendation, it’s great. Another question you might be able answer, I’ve got underfloor heating downstairs, each room is on a separate thermostat, should it only work when the heating has been started by the conventional (now nest e) schedule/timer?
Need a little bit more information, pics are best, show all other controls motorised valves other stats etc
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Here are some photos, I’ve not changed a thing since it worked, other than the thermostat upstairs.


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So the broken Honeywell brought on both upstairs and underfloor or was that coincidence?
The way a mororised valve works is when the stat or controller sends power to the valve motor, it energises and makes a tiny micro-switch once opened, it is this switch that brings the boiler on, so you need a seperate valve for each zone, all the end switches from each individual valve are connected together, so any configuration of zones on or off can be achieved, does the new Nest E connect directly to your boiler ? it should connect to the corrosponding zone valve on the Brown wire of the valve
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Underfloor heating has a very long heat up time, often up to two hours.

So it needs to be turned on well before you want the rooms to be warm. Similarly it can be turned off an hour or so before you want the room to have been cooled down.

That normally needs a separate time clock or programmer.

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