3rd gen nest thermostat no hot water with Combi Boiler

[Probablybest]

I have a 3rd gen Nest thermostat that connects to my Vaillant ecoTEC pure 825 combination boiler. I’m having an issue that I have no hot water unless the radiators/heating is on. I have to keep setting my thermostat to higher than room temperature so that I can get hot water from the tap.

I can’t wrap my head around how I can have the heating off with Nest but still have hot water? I don’t have a hot water setting on my Nest thermostat. I’ve seen online that with a combi boiler that hot water should kick in regardless of the thermostat.

If I set Nest to manual and turn the radiators/heating off on the boiler I still have hot water. But when I do it on the nest thermostat the whole boiler goes off and the hot water turns cold.

Any ideas how this can be fixed?

Just as a note, this is a brand new boiler and nest thermostat that was fitted by a plumber this week.

 

[flameport]

But when I do it on the nest thermostat the whole boiler goes off

Do you mean the boiler has no power at all when the thermostat is off?

brand new boiler and nest thermostat that was fitted by a plumber this week.

Their responsibility to properly install it, which they evidently haven't done.

 

[Probablybest]

Yes when I touch anything on the boiler nothing happens unless I put the thermostat into manual mode

 

[muggles]

Any ideas how this can be fixed?

Just as a note, this is a brand new boiler and nest thermostat that was fitted by a plumber this week.

Yes, call the installer back, as it seems they've made an error somewhere