Boiler heats but radiators only get lukewarm; system struggles to reach set temperature.

Safety first: Allow the system to cool before bleeding radiators or opening any valves.

• Check boiler power setting: Some Elnur models allow limiting of maximum kW output. Verify that the setting matches the boiler's rating and system requirements.
• Bleed radiators: Release trapped air from all radiators, starting with those furthest from the boiler. Top up system pressure afterwards if sealed.
• Check for cold spots: Radiators cold at the bottom may indicate sludge. Consider system flushing.
• Test elements: Measure current draw or resistance of each element bank. Replace any failed elements to restore full capacity.
• Assess sizing: If all components are working but the property still does not reach temperature in cold weather, the boiler may be undersized and require a heat loss assessment.