News

Reasons for frequent self-sealing and nozzle failure of fuel dispensers

News 2026年 7月 28日 40

Installing a fuel dispenser correctly is essential for ensuring safe fuel delivery, accurate measurement, and long-term equipment reliability.

Although a fuel dispenser looks simple from the outside, it is actually a complex system that integrates:

1. Preparation Before Installation

Before installing a fuel dispenser, the installation site must be carefully inspected.

The following conditions should be confirmed:

1. The dispenser foundation is stable and level.
2. Underground fuel tanks and pipelines are properly installed.
3. Electrical cables and communication lines are prepared.
4. The grounding system meets safety requirements.
5. The fuel pipeline is clean and free from impurities.

Before connecting the dispenser, the inside of the fuel tank and pipeline should be cleaned.

Foreign materials such as:

1. Welding residue
2. Dust
3. Metal particles
4. Construction debris

may enter the dispenser and damage precision components, including:

1. Fuel pump
2. Solenoid valve
3. Flow meter
4. Control valve

2. Fuel Pipeline Connection

The fuel pipeline connection is one of the most important installation procedures.

A correct pipeline connection ensures stable fuel supply and prevents leakage problems.

The normal fuel delivery path is:

Underground Tank

↓

Fuel Pipe

↓

Pump System

↓

Filter

↓

Air Separator

↓

Flow Meter

↓

Control Valve

↓

Fuel Nozzle

↓

Vehicle

During installation, pay attention to:

Correct Pipeline Direction

The fuel inlet direction must match the dispenser design.

Incorrect installation may cause:

1. Low fuel flow
2. Pump overload
3. Unstable dispensing performance

Pipeline Sealing

All pipe connections must be properly sealed.

Poor sealing may lead to:

1. Fuel leakage
2. Air entering the system
3. Reduced suction efficiency

3. Electrical Installation and Grounding

Modern fuel dispensers rely on electronic control systems to manage operation.

The electrical system usually includes:

1. Main control board
2. Metering controller
3. Display module
4. Encoder
5. Communication interface
6. Payment system

Proper wiring is essential for safe operation.

Grounding Protection

A reliable grounding system helps:

1. Prevent static electricity accumulation
2. Reduce electrical risks
3. Protect operators and equipment

Power Connection

Before powering on:

1. Confirm voltage requirements.
2. Check wiring connections.
3. Ensure cable protection is installed correctly.

Incorrect electrical connections may damage electronic components.

4. Commissioning After Installation

After installation, the dispenser should be tested before normal operation.

The commissioning process includes:

Pipeline Leakage Inspection

Check all fuel connections to ensure:

1. No leakage
2. Proper sealing
3. Stable pressure

Fuel Flow Test

Verify:

1. Pump operation
2. Fuel delivery speed
3. Flow stability

Meter Calibration

The flow meter should be calibrated to ensure:

1. Accurate measurement
2. Reliable fuel transactions

Nozzle Operation Test

Check:

1. Fuel dispensing performance
2. Automatic shut-off function
3. Nozzle sealing condition

5. Common Problem: Fuel Nozzle Frequently Shuts Off

One of the most common issues after installation is:

The nozzle automatically shuts off repeatedly during refueling.

Possible Causes

The automatic nozzle uses a sensing system to detect fuel level changes.

During operation, abnormal negative pressure may occur when:

1. The sensing hole is blocked.
2. Foreign materials enter the nozzle.
3. The vapor recovery system is abnormal.

This may cause:

1. Frequent automatic shut-off
2. Difficulty opening the nozzle
3. Interrupted fueling

Troubleshooting Steps

1. Check the Nozzle Sensing Hole

Inspect whether the sensing hole is blocked by:

1. Dirt
2. Dust
3. Fuel residue

Clean the area carefully before testing again.

2. Check the Fuel Pipeline

Inspect:

1. Pipeline cleanliness
2. Pipe connection condition
3. Air leakage problems

A blocked pipeline can affect fuel supply stability.

3. Check the Vapor Recovery System

For vapor recovery systems, abnormal air pressure may affect nozzle operation.

Check:

1. Recovery pipe condition
2. Air passages
3. Internal blockage

6. Common Problem: Nozzle Does Not Automatically Shut Off

Another common issue is that the nozzle cannot automatically stop when the tank is full.

Possible Causes

The main reasons include:

Foreign Material Inside the Valve

Debris inside the nozzle valve may prevent normal movement.

Secondary Valve Sticking

The internal valve may become stuck due to:

1. Dirt
2. Fuel residue
3. Mechanical wear

Solution

Recommended troubleshooting steps:

1. Remove the nozzle tube.
2. Inspect internal valve components.
3. Remove foreign materials.
4. Reassemble the nozzle.
5. Test automatic shut-off function.

7. Final Installation Checklist

Before putting the fuel dispenser into operation, confirm:

✓ Fuel pipelines are correctly connected
✓ No fuel leakage exists
✓ Electrical wiring is correct
✓ Grounding system works properly
✓ Communication system operates normally
✓ Flow meter calibration is completed
✓ Nozzle functions correctly
✓ Emergency shut-off system works properly

Conclusion

A successful fuel dispenser installation requires more than simply connecting pipelines and electricity.

It requires coordination between:

1. Mechanical components
2. Fuel delivery systems
3. Metering devices
4. Electrical controls
5. Safety protection systems

Proper installation and commissioning can significantly improve:

1. Equipment reliability
2. Fuel measurement accuracy
3. Operating safety
4. Service life

By following professional installation procedures and performing regular inspections, gas station operators can achieve safer, more efficient, and more stable fuel dispensing operations.