Troubleshooting Guides
Diagnose and resolve common issues with fuel dispensers, submersible pumps, tank monitoring systems, and petroleum components using our step-by-step troubleshooting guides.
Troubleshooting Approach
Follow this systematic approach to diagnose issues accurately before replacing parts or scheduling a service call.
Identify the Symptom
Clearly define the problem — no flow, error code, unusual noise, leak, or power failure. Note when the issue started and any recent changes to the system or environment.
Check the Basics
Verify power supply, fuel level, valve positions, circuit breakers, and any displayed error codes before proceeding. Many issues have simple root causes that are easy to overlook.
Isolate the Component
Narrow the problem to a specific component — dispenser, pump, sensor, valve, or electrical panel. Use diagnostic features or the equipment manual to pinpoint the fault.
Contact Support If Needed
If the issue persists, contact our team with your equipment model, serial number, and a description of the symptoms. We'll help diagnose and recommend the correct replacement parts.
Issues by Equipment Type
Find your equipment category and match the symptom to its most common causes. Use this as a starting point before ordering parts or scheduling service.
Fuel Dispensers
- No fuel flowClosed emergency shutoff, tripped shear valve, failed solenoid, or low tank level.
- Slow or intermittent flowClogged filter, worn nozzle, restricted hose, or failing pump motor.
- Display not workingBlown fuse, loose wiring, failed display module, or power supply fault.
- Meter inaccuracyAir in the line, worn meter internals, calibration drift, or temperature shift.
Submersible Pumps
- Pump not startingTripped breaker, failed control box, motor winding fault, or wiring damage.
- Low flow or pressureWorn pump stages, air leak in drop pipe, or partially closed check valve.
- Pump runs continuouslyStuck float switch, failed check valve allowing back-drain, or line leak.
- Noisy operationWorn bearings, cavitation from low fuel, or loose pump column assembly.
Tanks & Containment
- Liquid in spill bucketRainwater intrusion, overfill during delivery, or a fitting leak above the bucket.
- Sump alarm activeLiquid accumulation from condensation, a leak, or a failed sump sensor.
- Overfill valve not seatingDebris in valve seat, valve age or wear, or incorrect installation depth.
- Tank gauge reading errorProbe float stuck, wiring fault, or ATG configuration issue.
Electrical & Sensors
- Leak detector alarmActual liquid detected, sensor fouling, wiring fault, or incorrect setup.
- Dispenser trips breakerShort circuit in wiring harness, failed solenoid, or ground fault.
- Sensor reading erraticCorroded contacts, water intrusion into conduit, or loose terminal.
- Control box fault lightMotor overload, phase fault, or internal control board failure.
Valves & Fittings
- Check valve not holdingWorn or damaged disc/seat, debris lodged in valve, or spring fatigue.
- Shear valve won't resetImpact damage to poppet mechanism, or not fully realigned after actuation.
- Fuel odor at fittingsLoose threaded connection, cracked fitting body, or failed gasket/O-ring.
- Pressure relief ventingExcessive tank pressure, blocked vent line, or incorrect relief setting.
Vapor Recovery
- Nozzle leaking vaporWorn face seal, cracked bellows, or damaged poppet spring.
- PV vent cycling excessivelyPressure imbalance in tank, blocked vent line, or incorrect vent setting.
- Stage II test failureFailed coaxial hose, leaking breakaway, or out-of-spec nozzle.
- Fuel odor at vent pipeFailed PV vent, blocked carbon canister, or overpressure condition.
Can't identify the cause? Contact our technicians with your equipment model, serial number, and a clear description of the symptom — we'll help you diagnose the issue before you order.
Troubleshooting Best Practices
Follow these guidelines when diagnosing petroleum equipment issues to avoid misdiagnosis, unnecessary part replacement, and further damage.
Never Ignore Error Codes
Modern dispensers and ATG systems display fault codes for a reason. Always look up the code in the equipment manual before resetting it. Clearing a code without addressing the root cause can allow a hazardous condition to persist.
Check the Simplest Things First
Before assuming a component has failed, verify power supply, fuel level, valve positions, and circuit breakers. A large number of service calls are resolved by confirming these basics.
Do Not Run a Pump Dry
Operating a submersible or suction pump without fuel causes rapid wear to pump stages and bearings. If flow suddenly drops to zero, check fuel level before cycling the pump repeatedly.
Isolate Before Replacing
Replacing parts based on a guess is expensive and may not solve the problem. Always test to confirm the suspected component is actually at fault — use a multimeter for electrical issues or a pressure gauge for hydraulic ones.
Document Every Symptom
Write down exactly what the equipment is doing, when it started, error codes displayed, and any recent work performed. This information is critical when seeking help from our technicians or a service contractor.
Use OEM or Equivalent Parts
When replacing a failed component, always use the correct OEM part or a verified equivalent. Installing a non-specified part can introduce new problems and potentially void your equipment warranty.
If you suspect a fuel leak, release, or fire hazard — stop operations immediately, evacuate the area if necessary, and contact emergency services. Do not attempt to troubleshoot active fuel releases.
Troubleshooting FAQs
Answers to the most common diagnostic questions from petroleum equipment operators and service teams.
Look up the error code in your dispenser's service manual for the specific model. Common codes relate to communications faults, solenoid errors, or meter failures. If you don't have the manual, contact our team with your dispenser model and we can help identify the code.
The most common causes are a failed or stuck check valve causing back-drain, air trapped in the drop pipe, worn pump stages that can no longer build pressure, or a blocked line filter. Start by checking the filter and listening for unusual motor noise that could indicate stage wear.
Leak detector alarms can be triggered by actual liquid in the sump (even small amounts of condensation), a faulty or fouled sensor, damaged wiring, or a configuration issue. Inspect the sump physically before assuming a false alarm — never silence an alarm without physical verification.
For mechanical components like nozzles, valves, and filters, cleaning is often a valid first step. For electrical components showing fault codes or intermittent behavior, replacement is usually more reliable than attempting repair. Our team can advise on whether a repair or replacement is the right call for your specific situation.
Basic diagnostics — checking power, fuel levels, valve positions, and error codes — can be performed by a qualified site operator. However, any physical repair, component replacement, or work on electrical systems in classified hazardous locations must be performed by a licensed and qualified technician.
Have the following ready: equipment manufacturer and model number, serial number, a clear description of the symptom, any error codes displayed, when the problem started, and any recent work or changes made to the system. This allows our technicians to diagnose faster and recommend the correct replacement parts.
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