Vaillant VRT350 to Tado smart thermostat

[k.udhay]

TL;DR

electronics at all.

Hello,

My house has a Vaillant VRT350 thermostat fixed on wall. I want to change it to a smart thermostat and found Tado to be interesting so far.

Which model should I buy?

Here are my requirements on the device:

1. I want this new device to facilitate me control the desired temperature by my phone.
2. This should "NOT" control my hot water supply for shower. The existing system is already just good.

Here are my requirements on the installation:

1. I am not good with electronics at all. I can only do basic electrical things like connecting lamps & switches. Not at all good with understanding complex circuit diagrams. So, the installation should be simple to replace existing thermostat with Tado. (No touching of the boiler at all)

2. I don't want a system that expects me to change battery at some intervals - Thus, I prefer a wired system.

3. [Question] If there is a wifi failure in peak winter, will the system at least ensure that the radiator pipes don't go below 5°C to avoid freezing.

In internet there was some info. about Opentherm vs relay that I couldn't understand well. Must I really understand it? Any specific concern of not paying attention to that?

Thanks a lot, in advance!

 

[pbuk]

The VRT350 is more than a simple thermostat and can be installed in many different system configurations. In order to install a Tado (or any other) smart thermostat you will need to work out which configuration you have and what other elements of the system need to be replaced by reverse-engineering the existing wiring and comparing it with the installation circuit diagrams for the whole system including the boiler and any controller wired to it.

1. I am not good with electronics at all. I can only do basic electrical things like connecting lamps & switches. Not at all good with understanding complex circuit diagrams. So, the installation should be simple to replace existing thermostat with Tado. (No touching of the boiler at all)

Given what I have written above, you need to find a central heating engineer to advise you.

2. I don't want a system that expects me to change battery at some intervals - Thus, I prefer a wired system.

I suggest that you drop this requirement: most smart systems have batteries somewhere.

In internet there was some info. about Opentherm vs relay that I couldn't understand well. Must I really understand it? Any specific concern of not paying attention to that?

Vaillant use a proprietory system instead of Opentherm, although there is a converter module available. You need to leave this to someone with better knowledge and experience.

 

[sophiecentaur]

Given what I have written above, you need to find a central heating engineer to advise you.

With the OP's lack of tech knowledge then there's no alternative. If you already know what you want your system to do then you wouldn't need to pay a lot more than a call-out charge if your existing system is not too elderly. If it is old then he should consider saving a load of running costs b y buying a new one. (Scrambled pronoun s here but no matter.)
As for his problem with replacing / recharging batteries the proprietary wireless thermostats work virtually for ever on two AA cells. He has, presumably come to terms with recharging a smart phone every one or two days and we're talking over a year replacement for a simple, low data rate thermostat. Not an issue. It's like TV remotes.