Furnace runs, but radiators stay lukewarm; the home does not reach the set temperature.

Safety first: Turn off power and gas before opening any panels. Hot water and surfaces can cause burns.

• Check thermostat and settings: Confirm the room thermostat is set high enough and that the boiler flow temperature is not set too low on the control panel.
• Bleed radiators: Release trapped air from radiators, starting with the upper floors. Top up the system pressure afterward.
• Check pump speed: Many Roca pumps have selectable speeds or modes. Set it to a higher speed if the system is large.
• Inspect return temperature: If the return pipe is nearly as hot as the flow near the boiler, but radiators are cool, there may be bypass valves or balancing issues that need adjustment.
• Professional service: Have a technician check the gas rate, clean the primary heat exchanger, and flush the system if sludge is suspected.

Warning: Gas adjustments and chemical flushing should only be performed by qualified personnel.