- Hi. I got a new alarm system isntalled on Friday and the nest link is no longer connecting to the thermostat and isn't showing any lights at all. The thermostat is saying error h71. We have a second thermostat which is working perfectly. Both link boxes are right beside each other and the alarm the hnician said he didn't go near them or their power source.
The main issue is this is the thermostat used to heat our water. Is there a way if overriding the next. Google is telling me to press the heat link button but this is t working as it has no power.
TIA
