An apparatus for detecting fire and preventing explosion in a transformer, the apparatus comprising: at least one voltage variation detection unit for determining a ratio of an input voltage entering the transformer and an output voltage exiting the transformer, wherein the at least one voltage variation detection unit is configured to provide a first input signal to at least one control unit, when the ratio of the input voltage and the output voltage surpasses a preset threshold ratio; an over current detection unit configured for monitoring a load on the transformer, thereby providing a second input signal to the at least one control unit when the load on the transformer surpasses a preset load threshold; at least one surge detection unit and at least one Rapid Pressure Rise Relay, RPRR, configured for detecting oil surge and variation of oil pressure within a transformer tank of the transformer, thereby providing a third input signal to the at least one control unit, when the oil surge and the variation of oil pressure in the transformer tank surpasses a preset pressure threshold; one or more circuit breakers (24, 28) configured for receiving input signals from either one of the at least one voltage variation detection unit, the over current detection unit, the at least one surge detection unit and the at least one rapid pressure rise relay, RPRR, wherein the one or more circuit breakers (24, 28) provides a fourth input signal to the at least one control unit; and the at least one control unit is configured to generate a control signal for operating a drain valve and a gas release valve upon receipt of either one of the first input signal, the second input signal, the third input signal and the fourth input signal, wherein, the gas release valve comprises: a primary gas valve configured with a primary inlet port fluidly connected to a gas source, and a primary outlet port; a secondary gas valve configured with a secondary inlet port, fluidly connected to the primary outlet port, and a secondary outlet port fluidly connected to the transformer tank for routing gas into the transformer tank, when the primary gas valve and the secondary gas valve are operated by the at least one control unit; and an exhaust port configured to exhaust the gas leaked from either one of the primary gas valve and secondary gas valve to the atmosphere, when the primary gas valve and the secondary gas valve are in closed position. at least one voltage variation detection unit for determining a ratio of an input voltage entering the transformer and an output voltage exiting the transformer, wherein the at least one voltage variation detection unit is configured to provide a first input signal to at least one control unit, when the ratio of the input voltage and the output voltage surpasses a preset threshold ratio; an over current detection unit configured for monitoring a load on the transformer, thereby providing a second input signal to the at least one control unit when the load on the transformer surpasses a preset load threshold; at least one surge detection unit and at least one Rapid Pressure Rise Relay, RPRR, configured for detecting oil surge and variation of oil pressure within a transformer tank of the transformer, thereby providing a third input signal to the at least one control unit, when the oil surge and the variation of oil pressure in the transformer tank surpasses a preset pressure threshold; one or more circuit breakers (24, 28) configured for receiving input signals from either one of the at least one voltage variation detection unit, the over current detection unit, the at least one surge detection unit and the at least one rapid pressure rise relay, RPRR, wherein the one or more circuit breakers (24, 28) provides a fourth input signal to the at least one control unit; and the at least one control unit is configured to generate a control signal for operating a drain valve and a gas release valve upon receipt of either one of the first input signal, the second input signal, the third input signal and the fourth input signal, wherein, the gas release valve comprises: a primary gas valve configured with a primary inlet port fluidly connected to a gas source, and a primary outlet port; a secondary gas valve configured with a secondary inlet port, fluidly connected to the primary outlet port, and a secondary outlet port fluidly connected to the transformer tank for routing gas into the transformer tank, when the primary gas valve and the secondary gas valve are operated by the at least one control unit; and an exhaust port configured to exhaust the gas leaked from either one of the primary gas valve and secondary gas valve to the atmosphere, when the primary gas valve and the secondary gas valve are in closed position. a primary gas valve configured with a primary inlet port fluidly connected to a gas source, and a primary outlet port; a secondary gas valve configured with a secondary inlet port, fluidly connected to the primary outlet port, and a secondary outlet port fluidly connected to the transformer tank for routing gas into the transformer tank, when the primary gas valve and the secondary gas valve are operated by the at least one control unit; and an exhaust port configured to exhaust the gas leaked from either one of the primary gas valve and secondary gas valve to the atmosphere, when the primary gas valve and the secondary gas valve are in closed position.