I am also having the same issue as many others, heatlink is dead, thermostat shows H72 error code.
I have read the other links and carried out procedures as advised but no luck
- Does anything happen if you press its button for 30 seconds? Nothing
- In some cases the boiler will have an additional isolation switch which can turn off the power to both the Heat Link and the boiler. Can you try switching that off/on again to see if anything changes? Done – no change
- Make sure the breakers are on or the fuse board hasn't tripped. Reset everything – No Change
Moreover, to have a better view over each of your cases, please help us with some answers:
- How often do you experience the issue? Once
- How long has your thermostat been installed for? 16 months
- What colour is the Heat Link LED? No Lights come on
- What is showing on the Nest thermostat display? H72
- Have you had any power cuts recently? No
- Have you had any work done on your electrical or heating systems recently? No
- How many zones are present in the setup? One
- Is there power present to your boiler? Yes
Help required, please
