Diagnose Thermocouple & E-Mag Faults Professionally
Stop guessing and replacing parts blindly. GasCalc provides the ultimate diagnostic tool to accurately determine whether a pilot outage is caused by a failing thermocouple or a shorting magnetic power unit (E-Mag) inside the gas valve using a 3-point millivolt load test.
Demo Video Coming Soon
Core Capabilities & Audit-Ready Reporting
Turn your multimeter readings into actionable fault diagnosis instantly.
Load Test Analysis
Input your Open Circuit (OC) and Closed Circuit (CC) millivolt readings. GasCalc calculates internal resistance and load drop to determine if the thermocouple is weak or the coil is shorting.
Drop-Out Verification
Enter the Drop-Out (DO) voltage to verify the mechanical health of the valve's E-Mag spring and seal. Identify sticky valves or weak magnets before they cause nuisance outages.
Visual Diagnosis Matrix
A visual mapping chart plots your readings into 'Safe', 'Marginal', 'Replace TC', or 'Replace E-Mag' zones, taking the guesswork out of troubleshooting.
Data-Driven Compliance
Generates a complete, JSON-driven mathematical audit trail showing every formula, input, and conversion step.
Inspector-Ready Output
Outputs crisp, vector-based PDF reports directly from the field, providing Technical Regulators with the exact, unassailable mathematical proof required to certify Type B appliance ignition sequences.
How the Diagnostic Works
A multimeter test accurately determines whether a pilot outage is caused by a failing thermocouple (low output/high internal resistance) or a shorting magnetic power unit (E-Mag).
Open Circuit Test (OC)
Disconnect the thermocouple from the valve. Heat the tip with the pilot flame for 60 seconds. Read the voltage directly across the tip and the copper sheath.
Closed Circuit Test (CC)
Install a thermocouple test block/adapter between the thermocouple and the gas valve. Light the pilot and take the reading under load.
Drop-Out Test (DO)
Turn the gas supply to the pilot OFF. Record the exact voltage at the moment you hear the "click" of the valve shutting.
Diagnostic Logic
Target OC (Open Circuit)
Between 25mV and 35mV. If under 20mV, the thermocouple is generally weak and should be replaced.
Target CC (Closed Circuit)
Roughly half of the OC (10-15mV). If the reading drops too low, the thermocouple fails under load. If it reads too high (near the OC), the E-Mag coil has failed.
Target DO (Drop-Out)
Valve should release between 1mV and 5mV. If it clicks out above 5mV, the magnet is weak. If below 1mV, the valve is dangerously sticky.
GasCalc protects you from misdiagnosing faults and wasting time and parts.
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