I have two nest thermostats, one upstairs and one downstairs. The heating has an upstairs and a downstairs circuit so each thermostat is connected to its own heat link module, so they are designed to run independently. When they were installed they worked as they should - each followed the temperature and schedule set.
However, recently the downstairs heating does not come on when it should (ie the set temp is below the actual) - it glows orange on the stat and on the app and says its heating but the heatlink does not respond by triggering the heating system.
If the upstairs heating happens to come on, though, the downstairs does kick into life and start circulating and heating.
How can I solve this?
