Software update issue

[pyrmont25]

Can someone please tell me the latest software version for the UK Nest 3rd generation learning thermostat? All the posts and information seem to relate to the US versions. My thermostat keeps telling me the software is up to date but there have been several new releases which appear on the Google software version history. I need information for the UK thermostat please.

[Frustratedddd]

Latest UK software for the 3rd gen is 5.9.5-2

That was updated last year in November. All updates can be seen here......

Clearly states it as..

https://support.google.com/googlenest/answer/9263516?hl=en-GB

Version 5.9.5-2 – released November 11, 2021 (EU only)

• Bug fixes and enhancements.

You say your thermostat says it's up to date, and if you are on 5.9.5-2, then you are up to date.

[pyrmont25]

Ok thanks. Yes, current version is 5.9.5-2 so I am up to date. Appreciate your help!

[AlexD]

Thanks for reaching out to us here @pyrmont25 . That is indeed the latest version for the UK version of the thermostat, thank you for the information and link @Frustratedddd , much appreciated. 

Make sure to let me know if you need assistance with anything else. 

[AlexD]

Hi, just wanted to check in. Is there anything else you need assistance with? If so, make sure to let me know. 

[pyrmont25]

There is much confusion over the supply voltage for the nest thermostat. I have a UK 3rd generation learning thermostat. The heat link supplies 12V DC, the Google nest website says the supply to the thermostat should be 24V AC and the USB connection is 5V DC. I connected a 24V AC supply which made the thermostat run hot and gave incorrect temperatures. I cannot supply it from the heat link because of cable issues so can you confirm what the correct supply voltage should be? I wish to wall mount my thermostat but have no idea what the supply should be.

[Frustratedddd]

I have never seen any information about a UK thermostat running at 24v AC, the Heat Link clearly states 12v also inside the cover.

Yes it can use a usb connection as you state at the base ring for wireless connections, but for 24v I have never seen that.

Can you show where that information about the 24v for a UK thermostat?

[AlexD]

Hi @pyrmont25 , thanks for reaching out. I would be happy to try and assist to clear things up.

Thank you for the input @Frustratedddd, you are on point. The Heat Link does indeed only offer 12 V DC to the thermostat.

To clarify, the US version of the thermostat is the one that runs off 24 V AC. The US one does not have a Heat Link and the base of the thermostat is connected directly to the system.

The UK, and EU, versions have the Heat Link unit. The Heat Link is connected to high voltage 240-220 V AC and provides 12 V DC over the T1, T2 terminals to the T1, T2 terminals on the thermostat base. So the thermostat base can be either connected to the Heat Link for power or using a micro USB cable and a power adapter, like when you put it on a stand. 

So you may see on some sites that 24 V AC may be mentioned, but that is only for the US version of the thermostat.

[Frustratedddd]

I can understand where pyrmont25 is coming from as the internet covers mainly USA thermostats. Even on here, it's very difficult to work out which system is being used by the person posting the problem. You should have a section for UK/Europe and one for USA, then perhaps users could post in the correct location.

Having said that, the UK install manual and Heat Link, clearly states 12v for thermostat display. The obvious get out clause by Google at the top of the install manual is: ''The Nest Learning Thermostat for the UK and Ireland should be installed by a professional''

[AlexD]

Correct, it can certainly get confusing if the system is not correctly identified. Tho we can generally quickly identify what thermostat or system we are referencing.

That is correct, we recommend the 3rd Generation be installed by a professional. This is not so much related to the display, as that is only 12 V DC, but the Heat Link, where you will be working with high voltages. Also, identifying the correct valves, terminals and other elements in the system can be tricky depending on the system at the location. We have the Google Nest E version that is recommended for a DIY option.  

[pyrmont25]

Thanks everyone for your help and feedback with this. We should definitely have different sections for the US and UK. The information gets very confusing when trying to sort issues, hence my confusion over the latest software. Clearly the UK/EU software updates are different to the US as are the installation instructions. The are 24V transformers being sold on Amazon claiming to be compatible with all Nest thermostats. This is completely wrong as I found out by purchasing one. 

[AlexD]

Thanks for keeping us posted and thanks for the feedback. I am glad to hear things are clear now. make sure to let us know here if you have any further questions in a new thread, I will go ahead and close down this thread.

For a few more points of comparison, I also found this link from our support pages that might be helpful. It lists the differences between the US and EU one.