Vortex reconnections play a fundamental role in fluids. They increase the complexity of flow and develop small-scale motions. In this work, we report that in superfluids, they can also excite large scales. We numerically illustrate that during a superfluid vortex reconnection energy is injected into the thermal (normal) component of helium II at small length scales, but is transferred nonlinearly to larger length scales, increasing the integral length scale of the normal fluid. This inverse energy transfer constrasts with the reconnection-triggered energy transfer to smaller scales observed along the superfluid vortices and in classical fluids, underlining that similarities and differences between quantum and classical vortex dynamics may depend on the fluid component investigated. In addition, by studying about fifty different reconnections, we show that the reconnection event injects a non-zero net helicity in the normal fluid as a result of the chiral character of the mutual friction force coupling the superfluid vortices and the normal component, contributing to the understanding of the impact of topology-changing events on the helical balance of superfluid flows