Boiler makes gurgling or trickling water sounds inside the cabinet

Safety: Allow the system to cool before bleeding air.

• Check automatic air vent: Locate the air vent on or near the Dettson boiler. Ensure the cap is slightly open (per manual) to allow air to escape and that it is not leaking water.
• Bleed system: Bleed radiators and high points to remove trapped air.
• Verify fill pressure: Ensure system pressure is adequate to reach the highest point in the system.
• Replace faulty vent: If the automatic air vent is clogged or leaking, have it replaced.