Nest Controller with an Ideal FF250 Boiler

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Current System:

Ideal FF250 Boiler
Lifestyle LP522 Controller
Hot water storage tank
Room Thermostat
TRVs

I'm looking to improve my system by adding a Nest controller, but I'm not sure if it's compatible? The improvements I expect from adding a Nest are:

More accurate programs - i.e. more than 4 on/off triggers per day, and different programs per day
Separate control of hot water, particularly in summer when the heating isn't on
Ability to override when having an early night - "OK Google, heating off"
Possibly add some smart TRV's

Before I invest any cash, I'm looking to double check that my system is able to do all this? I'm an electrician so I'm fine with following wiring diagrams etc.. I'm just looking to make sure I don't rip the system apart to find this isn't possible.

Thanks in advance for any advice received.

[Razor]

Assuming you also have a cylinder thermostat and either a 3 port or two 2 port motorised valves it's definitely possible

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Would it be fair to assume that all the cabling will be at the LP522 controller and it would be a case of replacing the controller with the Nest "box of tricks"? Or, would I have to start running cables from the boiler, too?

I'll open up the controller and get a look at what's in there.

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I've got the Nest working by placing the control unit where the thermostat was in the circuit, so controlling the heating only.

I'm not sure how this heating system works; I can have my hot water on without heating but I can't have heating on without hot water. Is that a restriction on the controller or is it a restriction with the boiler/system? If it's a restriction with the system then I'm wondering if there's any point trying to integrate the Nest to control hot water?

If I could have heating on without hot water then I think that would give me a significant energy saving; I'm just not sure if that's possible?

[Razor]

No one can give you an answer without you telling us what controls you currently have in the way of motorised valves..........

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Yes, I understand. There's a junction box next to the boiler so I may be able to integrate the Nest in there. I think it's a gravity system which is why the hot water needs to be on when the heating is on. I can configure the Nest to call for water as well as heat by linking some contacts; I just need to suss out that junction box.

[ericmark]

I think with Ideal you have OpenTherm so for best control yes new wires thermostat to boiler to take advantage of OpenTherm, the MiHome Energenie range of TRV heads are designed to work with Nest, they use a follow command so either Nest follows the valve or the valve follows Nest, however that to me seems to defeat the whole idea of individual room control.

I fitted the TRV heads first with whole idea of adding Nest latter, however two things, one the valves worked well and found no real need for Nest once they were fitted, and two found Bosch does not support OpenTherm.

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I got it working. The system is pretty simple, 2 pumps and a tank thermostat. I have it set to call for hot water only when it calls for heat.

No more heating a tank of water 24/7.