Nest 3rd gen thermostat calling on hot water when not sheduled?

[Eamon]

Hi

Our zoned hot water valve fires up at random times. We have it to turn on as scheduled which works fine but when it should be off it comes on by itself? 

The electrician is adamant that it is wired correctly and I had a second guy look at the wiring and it seems fine?

Has anyone else had any problems like this?

Eamon

[AnaM]

Hey @Eamon,

I'm sorry to hear about your issue, but I'll do my best to help. Did you notice a pattern in this behavior? Also, when was your thermostat installed and when did this issue occur?

[Eamon]

Hi Ana.

It seems to come on around 11am but itself. 100% don't have it scheduled at this time. Some days around noon. And sometimes around 5pm. 

We installed it in December but because our heating was on alot we didn't really notice the boiler coming on. But couldn't understand how we went through so much oil. 

As we got into March and the heating on less we noticed the boiler coming on around 11am by itself. I would go to where zoned heating and hot water valves were and the hot water would be on. But hot water not scheduled. 

Thanks AnaM 

[AlexD]

Thank you for the information. Just to check first, are there any other timers or programmers in the system that could be influencing the schedule? Also, do you happen to know if the valve system you have there is a S or a Y plan valve system? The S plan has 2 separate valves, one for the heating and one for the water tank and the Y one has a single valve that controls both. 

[AlexD]

Hi, I wanted to check in. Do you still need assistance? If so, make sure to let me know. 

[DragosC]

Since I haven't heard from you in a while, I'll have to close this thread. Should anything else come up, please open another thread and we'll take it from there. Have a good one and stay safe!