Chaining two thermostat bridges

[oldbutnotdead]

Fair choice (bathroom and loos always warm). If you do go choice 2, you could end up with a nest v Tado sketch (where the Nest stat says its cold so fires the boiler, Tado valves are all up to temperature (or off) so unless the Nest stat is in the bathroom/loo the boiler will run continually through any Nest timed periods

 

[sndp]

Fair choice (bathroom and loos always warm). If you do go choice 2, you could end up with a nest v Tado sketch (where the Nest stat says its cold so fires the boiler, Tado valves are all up to temperature (or off) so unless the Nest stat is in the bathroom/loo the boiler will run continually through any Nest timed periods

I get what you mean, I'm aiming for a Nest as the master sort of control

Bring Nest up to 23c, all the TRVs will change their setpoints to 23c
I can change the TRV temps individually until the next Nest temp change or when home/away is triggered

 

[oldbutnotdead]

Mmm. Is home/away on the Nest and does it push a very low setpoint at the TRVs?

 

[sndp]

Mmm. Is home/away on the Nest and does it push a very low setpoint at the TRVs?

Home/Away is controlled by Tado, so if the Tado system detects that no one is within the geofence then the Nest switches to Away mode too. So there's no issue with the boiler/rads heating up while I'm away.

 

[graphium]

Hi All,

I am in a very similar situation as the thread starter. However, in my case I would like to have both controllers wired in parallel, so either of thermostats can call for heat and start the boiler, so effectively the boiler will supply heat unit both controllers are satisfied.

I have a Y plan system (1 heating zone), which currently is controlled by Nest 3rd gen. I have a quite old boiler, which is just controlled by 230V on/off. In my nest’s heatlink I have 230V wired to common (nest terminal 2) and then call for heat (nest terminal 3) is wired to my heating zone valve, which then when opens, powers the pump & boiler. I am going to add number of tado smart TRV’s and tado thermostat to my son’s bedroom, so it can also call for heat independently.

So in this scenario I would just add Tado controller in parallel to nest so both commons would be linked together and both “call for heat” would go to the same zone valve.

My question is: is there any risk of any damage of controllers/relays when only one of the controllers calls for heat when the other does not – so in this case let’s say that only nest calls for heat and sends 230V to the zone valve, and then the same 230V is fed back to tado “call for heat” (as they are now linked) - even though tado does not call for heat, it gets 230V fed back to call for heat terminal, any possible issues with this ?

 

[bernardgreen]

so if the Tado system detects that no one is within the geofence

How does the Tado systm detect that no one is within the geofence, ?

Does it rely on people living in the house carrying GPS activated mobile phones with them when in the house. ?

 

[graphium]

Hi All,

I am in a very similar situation as the thread starter. However, in my case I would like to have both controllers wired in parallel, so either of thermostats can call for heat and start the boiler, so effectively the boiler will supply heat unit both controllers are satisfied.

I have a Y plan system (1 heating zone), which currently is controlled by Nest 3rd gen. I have a quite old boiler, which is just controlled by 230V on/off. In my nest’s heatlink I have 230V wired to common (nest terminal 2) and then call for heat (nest terminal 3) is wired to my heating zone valve, which then when opens, powers the pump & boiler. I am going to add number of tado smart TRV’s and tado thermostat to my son’s bedroom, so it can also call for heat independently.

So in this scenario I would just add Tado controller in parallel to nest so both commons would be linked together and both “call for heat” would go to the same zone valve.

My question is: is there any risk of any damage of controllers/relays when only one of the controllers calls for heat when the other does not – so in this case let’s say that only nest calls for heat and sends 230V to the zone valve, and then the same 230V is fed back to tado “call for heat” (as they are now linked) - even though tado does not call for heat, it gets 230V fed back to call for heat terminal, any possible issues with this ?

I think I am going to give it a go over the weekend. I asked an electrician at work, And he thinks that shouldn't be a problem....