Unitech Combustion

Solenoid coils power the dual solenoid shutoff valves (V1 and V2) within the valve block, regulating staged fuel delivery: first-stage (low-fire) via V1, and second-stage (high-fire) via V2.

They operate on a 2-step voltage profile: high voltage (~29–30 V DC) during ignition to ensure rapid valve actuation, then a low holding voltage (~3 V DC) during steady operation to maintain the open position with minimal power consumption.

During ignition, the control box (RMO or equivalent) delivers the high voltage to swiftly open the valve, then reduces to a low holding voltage to sustain open status with minimal energy.

One commonly-used coil part number is 3002279 (~1 500 Ω), used across several G-series burners.

Another OEM coil for the PRESS G range is 3006714, listed as a solenoid coil oil burner coil used on GW/1G/2G/3G/4G models.

Mounting: Installed on the valve block assembly; ensure clean mounting surfaces and intact O‑rings/gaskets.

Wiring: Connected to the control box via dedicated terminals (e.g., “V1” and “V2”). Check for firm connections and good insulation.

Troubleshooting:

• If the coil is energized but oil flow does not begin, ensure high-voltage pulse is present during start—coils may stick if the initial voltage is missing.

• Measure resistance to confirm coil integrity (compare to ~1 500 Ω). Use a multimeter on DC current to verify high/low voltage switching during start and running phases.

Solenoid coils power the dual solenoid shutoff valves (V1 and V2) within the valve block, regulating staged fuel delivery: first-stage (low-fire) via V1, and second-stage (high-fire) via V2.

They operate on a 2-step voltage profile: high voltage (~29–30 V DC) during ignition to ensure rapid valve actuation, then a low holding voltage (~3 V DC) during steady operation to maintain the open position with minimal power consumption.

During ignition, the control box (RMO or equivalent) delivers the high voltage to swiftly open the valve, then reduces to a low holding voltage to sustain open status with minimal energy.

One commonly-used coil part number is 3002279 (~1 500 Ω), used across several G-series burners.

Another OEM coil for the PRESS G range is 3006714, listed as a solenoid coil oil burner coil used on GW/1G/2G/3G/4G models.

Mounting: Installed on the valve block assembly; ensure clean mounting surfaces and intact O‑rings/gaskets.

Wiring: Connected to the control box via dedicated terminals (e.g., “V1” and “V2”). Check for firm connections and good insulation.

Troubleshooting:

• If the coil is energized but oil flow does not begin, ensure high-voltage pulse is present during start—coils may stick if the initial voltage is missing.

• Measure resistance to confirm coil integrity (compare to ~1 500 Ω). Use a multimeter on DC current to verify high/low voltage switching during start and running phases.