Some rooms controlled by Danfoss smart thermostats are consistently too cold while others are comfortable.

Safety first: Manifold adjustments and actuator work should be done with the heating system depressurized if required. Isolate power before working on actuators.

Steps to diagnose and fix:

• 1. Verify thermostat-to-zone mapping: Confirm that each thermostat controls the correct actuator(s) on the manifold or radiators. Correct any wiring or configuration mismatches.
• 2. Compare schedules: Ensure that the cold rooms are not set to lower setpoints or ECO modes compared to other rooms.
• 3. Check actuator operation: Confirm that actuators for cold zones open when heat is demanded. Replace any that remain closed.
• 4. Balance the system: Adjust flow rates on the underfloor manifold or radiator valves to ensure adequate flow to all zones, following Danfoss and system design guidelines.

When to call a professional: Hydraulic balancing is best performed by a heating engineer with appropriate tools.