Flamco 27750 Flexvent 3/8" Automatic Float Air Vent User Manual

1. Introduction and Product Overview

The Flamco Flexvent 3/8" automatic float air vent is engineered for efficient and reliable removal of air from heating and cooling systems. Air in these systems can lead to noise, reduced heat transfer, and corrosion. This compact brass valve automatically discharges accumulated air, ensuring optimal system performance and longevity. Each Flamco Flexvent undergoes rigorous testing before leaving the factory to ensure quality and reliability.

The Flexvent is suitable for systems operating at temperatures up to 90 °C (with a peak tolerance of 120 °C) and pressures up to 6 bar (with a peak tolerance of 10 bar).

This image displays a cross-section of the Flamco Flexvent, revealing its internal float mechanism and valve assembly responsible for automatic air discharge.

2. Safety Information

• Always ensure the heating or cooling system is completely depressurized and cooled down before attempting any installation, maintenance, or removal of the Flexvent.
• Working with pressurized or hot systems can cause severe burns or injury.
• If you are unsure about any installation or maintenance procedures, consult a qualified heating engineer or plumber.
• Wear appropriate personal protective equipment (PPE), such as gloves and eye protection, during installation and maintenance.
• Do not tamper with the internal components of the Flexvent.

3. Product Components

The Flamco Flexvent is a self-contained unit. Its primary components include:

• Brass Housing: The durable outer casing that protects the internal mechanism.
• Float Mechanism: A buoyant component that rises and falls with the water level.
• Valve Assembly: Connected to the float, this opens to release air and closes to prevent water leakage.
• Red Cap: A manual cap on top that can be loosened for automatic operation or tightened to prevent air release during system filling or maintenance.
• 3/8" Male Thread: For secure connection to the system piping.

4. Setup and Installation

Proper installation is crucial for the effective operation of the Flexvent. Follow these steps:

1. Prepare the System: Ensure the heating or cooling system is completely drained and depressurized. Allow the system to cool down to a safe temperature.
2. Identify Installation Point: The Flexvent must be installed at the highest point of the system where air naturally collects. This is typically at the top of a boiler, a manifold, or a high point in the pipework.
3. Connect the Vent: Apply an appropriate thread sealant (e.g., PTFE tape or pipe dope) to the 3/8" male thread of the Flexvent. Screw the Flexvent securely into a compatible female threaded fitting on your system. Do not overtighten.

Figure 1 illustrates the initial step of connecting the Flexvent unit (A) to a compatible threaded pipe fitting (B) in the heating or cooling system.

4. Ensure Correct Orientation: The Flexvent must be installed vertically upright for the float mechanism to function correctly. Incorrect orientation will prevent proper air discharge.

Figure 2 demonstrates the importance of correct vertical orientation for the Flexvent (indicated by checkmarks) to ensure proper air venting, contrasting with incorrect horizontal placement (indicated by an 'X').

5. Loosen the Red Cap: Before refilling the system, slightly loosen the red cap (E) on top of the Flexvent by turning it counter-clockwise a few turns. This allows air to escape automatically. Once the system is filled and operating, ensure the cap remains slightly loosened for continuous automatic air purging.

Figure 3 highlights the action of slightly loosening the red cap (E) on top of the Flexvent. This step is crucial for enabling the automatic air purging function.

6. Refill and Test: Slowly refill the system. The Flexvent will automatically release air as the system fills. Monitor for any leaks around the connection point.

5. Operating Instructions

The Flamco Flexvent is designed for fully automatic operation once correctly installed and the red cap is loosened. It requires no manual intervention during normal system operation.

• Automatic Air Release: As air accumulates within the system and enters the Flexvent chamber, the internal float drops. This action opens the valve, allowing the trapped air to escape.
• Automatic Valve Closure: Once the air is expelled and water fills the chamber, the float rises, closing the valve and preventing water from leaking out.
• Continuous Operation: This cycle repeats continuously, ensuring that your system remains free of air pockets.

6. Maintenance

The Flamco Flexvent is designed for low maintenance. However, periodic checks can help ensure its continued optimal performance:

• Visual Inspection: Periodically inspect the Flexvent for any signs of external leakage or corrosion.
• Functionality Check: Listen for occasional hissing sounds, which indicate that the vent is actively releasing air. If the system is noisy or radiators are cold at the top, the vent might not be functioning correctly.
• Cleaning: The design of the Flexvent includes a protected sealing seat, which helps prevent dirt from interfering with its operation. If you suspect a blockage, it is recommended to replace the unit rather than attempt to disassemble it, as internal components are delicate.
• Replacement: If the Flexvent consistently leaks water or fails to vent air, it should be replaced. Always ensure the system is depressurized and cooled before removal.

Figure 4 provides a safety warning, indicating that the system temperature should be below 70°C before attempting to remove or service the Flexvent unit (F) to prevent burns.

7. Troubleshooting

If you encounter issues with your Flamco Flexvent, consider the following:

• Air Not Venting:
  • Ensure the red cap on top of the Flexvent is sufficiently loosened. It should not be fully tightened.
  • Verify that the Flexvent is installed at the absolute highest point in the section of the system it is intended to protect.
  • Check for any visible blockages around the vent opening.
  • If the issue persists, the internal mechanism might be stuck or clogged. Consider replacing the unit.
• Water Leakage from Vent:
  • Ensure the Flexvent is securely tightened into its fitting.
  • Check if the red cap is too loose or damaged. Tighten it slightly or inspect for damage.
  • The internal valve or float mechanism may be faulty or damaged, preventing it from sealing properly. In this case, the unit requires replacement.
• System Noise or Cold Radiators: These symptoms often indicate air in the system. Follow the steps for 'Air Not Venting' to ensure the Flexvent is operating correctly. If the problem persists, there may be other sources of air ingress or system issues that require professional diagnosis.

8. Specifications

Key technical specifications for the Flamco Flexvent 3/8" Automatic Float Air Vent (Model 27750):

This table provides an overview of various Flamco Flexvent models, detailing their dimensions, connection sizes, and corresponding article numbers for identification and selection.

9. Warranty and Support

For information regarding the warranty period and terms for your Flamco Flexvent, please refer to the documentation provided at the time of purchase or contact your retailer. Flamco products are manufactured to high standards, and specific warranty details may vary by region and distributor.

For technical assistance, product inquiries, or to locate an authorized service provider, please visit the official Flamco website or contact Flamco customer support directly. When contacting support, please have your product model number (27750) and purchase details readily available.

Flamco Official Website: www.flamco.com