The luminescence of the 630 nm band in ZnSe single crystals was studied under intracenter excitation (hvex < Eg). We obtained luminescence spectra at different temperatures, temperature dependences of photoluminescence intensity and photoconductivity, lux-ampere and lux-luminescence dependences both at low temperatures, when there is no thermal quenching, and at 270 K, when thermal quenching is observed. Comparing of the photoluminescence spectrum with the X-ray luminescence spectrum has showed that only one component of the 630 nm band with a hole luminescence mechanism is observed in the photoluminescence. Temperature dependences of photoluminescence intensity and photoconductivity indicate that at T > 250 K external quenching of photoluminescence is observed under intracenter excitation. Lux-ampere and lux-luminescent dependences also confirm this conclusion.