Hot water and heating comes on when i boost the hot water

[LeeH]

I have wired up up nestlink and nest thermostat is connected remotely to heatlink. But when I boost hot water on nest the boiler and heating and hot water comes on. Have I wired something up wrong on my heatlink or is it the type of heating system I have?

[Frustratedddd]

Your install is incorrect I would assume.

You should be able to press Boost for the HW, without heating on.

Which do you have System or Combi boiler?

[LeeH]

I have a conventional system boiler.

Thanks.

[Frustratedddd]

With a system boiler, you should be able to press boost for just HW, or schedule HW. Both ways should only give HW not heating as well.

Your heat link will have 2 sets of contacts, 1-3 are heating, and 4-6 hot water.

Your install sounds incorrect I'm afraid.