Nest heat link - installed too close - H71 error code

smithyj1986

Hi all,

I’ve had my nest thermostat connected and working flawlessly for 3 years until yesterday when all of a sudden it showed error h71 (failed link between the thermostat and heat link)

I’ve done all suggested ideas from google : full reset, moving the thermostat right next to the heat link, reconnecting the link using the code under the heat link and still nothing

i sent the below photo to the guy from google and he says the heat link is too close to the boiler. My argument was it has been there for 3 years and never had an issue although I appreciate their guide states it should be a minimum of 30 cm from boiler but can this really be the issue? 

There’s no new appliances that can cause interference and I’m reluctant to get a ‘pro’ engineer they recommend to come and move it for me (it was one of their recommended engineers that fitted it in its current location 

macman

Why would you need a 'pro' engineer to move it? You just need to isolate the power supply, remove the cover and relocate the mounting screws to move it down or left. Any competent DIYer or handyman with basic electrical knowledge can do that. I can't measure it from here, but it looks as those there is sufficient slack in the cabling to move it without recabling it back to the boiler circuit board?
It's possible that heat from the boiler has caused it to fail over time, possibly a dry solder joint? If so, you'll need to replace it-but try moving it first.