topic Re: Nest not working with hot water in Nest Thermostats

Nest not working with hot water

DrBob — Wed, 18 Jan 2023 18:26:02 GMT

I've just installed a nest 3rd generation and initially just connected up the hot water. The system is on a canal boat so easy to wire the 'call for heat' from the Webasto heater to either of the 2 relays (heating or hot water) on the heat link.

FIrst 2 days it worked great with the hot water schedule closing the relay in the heat link and providing 12V to the webasto call for heat.

Today however the webasto fired up on its own. I checked the heat link and the relay for the hot water had turned on ie pins 5 & 6 connected. I couldnt turn it off from the thermostat or from the app. Even turning the hot water off in the app did not open the relay. I disconnected the call for heat wire from the webasto - so it stopped heating.

I then tried to turn the heat link off and on. After turning it back on, the relay was not energised but after circa a minute the relay turned on on its own - even though the app is set for hot water off and no schedule to be on in the water heater schedule. Every time I power up the heat link it powers up the hot water relay. I dont think it is anything to do with the webasto as the heat link is no longer connected to it.

The heating relay seems to be pefroming correctly.

Any ideas? What am I missing

Re: Nest not working with hot water

DrBob — Thu, 19 Jan 2023 09:27:02 GMT

Ok, sorted it out.

It was the legionnares disease setting. The nest thinks the water hasnt been heated enough and we're all going to die and decides to fire up the water. Why doesnt the nest or the app show that!! Very poor programming! A child of 6 could do better to inform you why it has put the water on. And when it is on, you cant turn it off via the app or the thermostat - only by disabling the legionnares setting - so why not via the app.It took me a couple of hours searching the internet to find out about this setting. Nowhere is it to be found (easily) in the instructions.

Pretty poor show Google!!!! 1/10 for your efforts.

Re: Nest not working with hot water

Vladut — Thu, 19 Jan 2023 16:55:59 GMT

Hi there, thank you so much for letting us know. We're so sorry for any inconvenience caused by this! Please let me know if you need any further assistance. Have a great day ahead!

Re: Nest not working with hot water

Vladut — Sun, 22 Jan 2023 09:02:41 GMT

Hi there, just checking in with you. Do you still need help?

Re: Nest not working with hot water

DrBob — Sun, 22 Jan 2023 11:42:21 GMT

No help now required.

It would be good if the this issue was easier to find.

Pretty poor that the app or the nest does not say that the water is heating due to the legionaires setting.

Re: Nest not working with hot water

Vladut — Sun, 22 Jan 2023 11:46:26 GMT

Great to hear about this. I'm sorry for any inconvenience. I'll take this feedback further. Let me know if you need anything else.

Re: Nest not working with hot water

UanaC — Tue, 24 Jan 2023 11:50:44 GMT

Hello there! Just checking, do you still need our help?

Re: Nest not working with hot water

DrBob — Tue, 24 Jan 2023 13:03:10 GMT

See above

For the 3rd time, no, it is sorted.

Re: Nest not working with hot water

UanaC — Tue, 24 Jan 2023 16:33:02 GMT

Thanks for confirming! In that case, I'll close this thread. If anything comes up, feel free to reach out. Have a good one and stay safe.