Boiler runs but the house does not reach the set temperature; radiators are lukewarm.

Safety: Use caution when bleeding radiators; water may be hot.

• Step 1 – Check CH setpoint: On the Triangle Tube control, verify that the central heating setpoint is appropriate (e.g., 160–180°F for radiators, lower for radiant floors).
• Step 2 – Review outdoor reset: If using outdoor reset, ensure the curve is not set too low for current weather. Adjust as per the installation manual.
• Step 3 – Bleed radiators: Starting with the highest radiators, bleed air until water flows steadily. Top up the system pressure as needed.
• Step 4 – Verify valves and pump: Confirm that all radiator valves and balancing valves are open and the circulator is running.
• Professional help: If performance remains poor, a technician should check combustion efficiency, heat exchanger cleanliness, and system balancing.