Nest can't turn on hot water

[Tomsnest]

My nest thermostat has suddenly lost the ability to turn hot water on so we've had no hot water for 2 days. It had been working perfectly for 3 months up to this point.

When the schedule comes on or when I press boost on the thermostat the heatlink box clicks but does not trigger the valve to open, therefore not triggering the boiler to fire. If I press manual on the heatlink box, then both valves open and the boiler fires without any problems.

Can someone help me understand why manual mode on the heatlink is able to open the valve but my thermostat is not? The thermostat also has no problem controling the heating going on and off. This is driving me a bit nuts.

[AlexD]

Thanks for reaching out to us @Tomsnest . I would be happy to try and assist. 

It is great to hear you already did some tests to see how the Heat Link behaves.

To check, if you go next to the Heat Link and turn on the heating, by turning the temperature up so the display goes orange, and then also boost the hot water, does that activate the hot water side? 

[Tomsnest]

Hi there,

I changed the actuated valves over the weekend and all is working now. Feels like there should be some fairly basic logic on the thermostat that says the valve was unable to open...

[AlexD]

It's great to hear that things are back on track. The Heat Link acts like a On/Off switch for the control. If you can hear the click from the Heat Link and the system does not activate, that is generally a big clue that something else may be going on, such as with the valves. 

Thank you for the feedback. We're always looking for ways to improve our products and features. If anything else comes up, make sure to reach out again.

I'll go ahead and close this thread. If anything comes up, make sure to open a new one.