During titanium layer deposition with a hollow cathode arc discharge the integral energy influx to the substrate has been monitored by measuring temperature gradients. Discharge power and substrate voltage have been varied. Simultaneously, the plasma parameters in front of the substrate were determined by means of Langmuir-probe measurements. From the integral energy influx and the plasma parameters the contributions of the charge carriers and the heat radiation to the substrate heating were calculated. The contribution of the titanium condensation heat could be estimated by means of Rutherford backscattering and ellipsometrical measurements. It was found that heat radiation and charge carriers mainly contribute to the integral substrate heating. The contribution of condensation can be neglected.