Lamp module that is configured to be used as an immersion radiator in photochemical reactors, that comprises a support body with at least one light-emitting diode and a head part for electrical connection of the at least one LED and for holding the support body and an immersion pipe that delimits an immersion pipe interior in which the support body with the at least one LED is arranged, wherein the head part comprises connection lines (18, 18') for the supply and the discharge of a cooling liquid, and the support body is configured as a cooling body that delimits at least one internal fluid path as supply section for the cooling liquid, wherein the supply section is connected through the head part to a first connection line, characterized in that the cooling liquid is an electrically non-conductive liquid that is transparent for the wavelengths of the radiation emitted by the LEDs of the lamp module, and the immersion pipe interior delimited by the immersion pipe is filled with the electrically non-conductive liquid such that the at least one LED is immersed completely in the non-conductive liquid, wherein the connection lines (18, 18') for the supply and the discharge of the non-conductive liquid communicate with the immersion pipe interior, wherein the supply section that is connected through the head part to the first connection line opens at a side of the support body facing away from the head part into the immersion pipe interior, and wherein a second connection line that extends through the head part opens at the head part toward the immersion pipe interior, wherein the connection lines (18, 18') are connected for forming a circuit of the non-conductive liquid, wherein the circuit comprises at least one heat exchanger and a conveying device. a support body with at least one light-emitting diode and a head part for electrical connection of the at least one LED and for holding the support body and an immersion pipe that delimits an immersion pipe interior in which the support body with the at least one LED is arranged, wherein the head part comprises connection lines (18, 18') for the supply and the discharge of a cooling liquid, and the support body is configured as a cooling body that delimits at least one internal fluid path as supply section for the cooling liquid, wherein the supply section is connected through the head part to a first connection line, characterized in that the cooling liquid is an electrically non-conductive liquid that is transparent for the wavelengths of the radiation emitted by the LEDs of the lamp module, and the immersion pipe interior delimited by the immersion pipe is filled with the electrically non-conductive liquid such that the at least one LED is immersed completely in the non-conductive liquid, wherein the connection lines (18, 18') for the supply and the discharge of the non-conductive liquid communicate with the immersion pipe interior, wherein the supply section that is connected through the head part to the first connection line opens at a side of the support body facing away from the head part into the immersion pipe interior, and wherein a second connection line that extends through the head part opens at the head part toward the immersion pipe interior, wherein the connection lines (18, 18') are connected for forming a circuit of the non-conductive liquid, wherein the circuit comprises at least one heat exchanger and a conveying device.