The mathematical modelling and numerical simulation of a condenser is discussed. This mathematical model is part of the NLR approach to model and scale two-phase heat transport systems (for space). During a previous study the condensation length required for various gravity conditions, and working fluids has been investigated by means of simulation studies. In this report the existing condensation model is extended with the effect of pure (radial) conduction via the growing condensate layer to the condenser wall. The effect of this extension is investigated by simulation studies.