Nest 2nd Gen + Combi Boiler = no more on demand hot water?

crzg

Hi there

I just had a Nest installed (2nd Gen).

I have a combi boiler that heats my rads and water on demand (I. E. I turn the hot water tap, the boiler kicks in and heats the water)

My understanding from research is that combi boilers are compatible with 2nd gen nest.

It seems that at present the hot water only works when the Nest is heating the rads. Turning the hot water tap does not trigger the boiler to kick in as I was expecting.

Is this normal?? I am aware that I was never going to be able to control the water temp from the Nest but can't find anything definitive explaining that this should result (only sources I can find on the Nest site explain that I can't control temperature.. Not that it cuts off access unless heating the house)

I was under the impression that using the hot taps would kick in the boiler..

Could this be a mistake with the install?

Otherwise pretty fair for Nest to be very clear that it's product neutralizes on demand hot water, I Hi there

I just had a Nest installed (2nd Gen).

I have a combi boiler that heats my rads and water on demand (I. E. I turn the hot water tap, the boiler kicks in and heats the water)

My understanding from research is that combi boilers are compatible with 2nd gen nest.

It seems that at present the hot water only works when the Nest is heating the rads. Turning the hot water tap does not trigger the boiler to kick would rather not have to manually turn on the boiler in my kitchen when I need to wash my hands in the toilet!

ArthurG

We have a combi-boiler and Nest (1st gen) at home. No problems with hot water. Nest controls the rads only, the circuit (I assume that's what you call it), for the hot water temp is set separately and fires up as required.

Dardania

In prinicple, as ArthurG notes, there should be no impediment to getting hot water due to use of the Nest. I would say it's most likely an install issue.

Before you call back the installer, there is possibly something you can do to address - on the boiler control panel, is there a multi position switch showing a tap and radiators? it should be set to both tap and radiators positon (meaning it should respond to hot water demand for th ehot water, and listen to the nest for raditators)

ArthurG

Dardania wrote: »

..... is there a multi position switch showing a tap and radiators? it should be set to both tap and radiators positon (meaning it should respond to hot water demand for th ehot water, and listen to the nest for raditators)

Yep, that's the setup we have.

crzg

Thanks guys,

I have an Arca Boiler (I can't post a link as I have <25 posts - google "Arca Pixel manual" and you'll see it come up)

The water temp is controlled via a digital display that only turns on when the boiler is powered up.

At the moment, when the Nest triggers a rise in temperature the boiler is powered on; otherwise the boiler is totally off (e.g. display turns off altogether) so in essence the Nest controller is cutting all power to the entire system which might be why the hot water doesn't trigger?

Should it be the case that the boiler is shut down without the Nest telling it to power up?

Thanks folks really appreciate it!

crzg

crzg wrote: »

Thanks guys,

I have an Arca Boiler (I can't post a link as I have <25 posts - google "Arca Pixel manual" and you'll see it come up)

The water temp is controlled via a digital display that only turns on when the boiler is powered up.

At the moment, when the Nest triggers a rise in temperature the boiler is powered on; otherwise the boiler is totally off (e.g. display turns off altogether) so in essence the Nest controller is cutting all power to the entire system which might be why the hot water doesn't trigger?

Should it be the case that the boiler is shut down without the Nest telling it to power up?

Thanks folks really appreciate it!

Combis are designed to give instantaneous hot water and to do such require a permanent electrical supply, external heating control are usually wired to a separate point on the boiler so as not to interfere with the running of hot water so long story short, it ain't wired right.

crzg

Thanks Gary! I checked the manual, if I'm right, page 9 of this manual shows a "AMBIENT THERMOSTAT / REMOTE CONTROL (OPTIONAL)"

http://www.arcacaldaie.com/Apps/WebObjects/ArcaCaldaie.woa/wa/viewFile?wantContent=true&id=254&lang=eng

I presume that's where the controller should have been wired in?