A pseudo-2D reactor model is used to perform a comprehensive study on the catalytic ignition of a lean propane/air mixture in a microreactor with Pt-coated walls. The results of the in-house code are verified against the commercial package FLUENT. The roles of inlet velocity, wall conductivity, heat losses or heat transfer to an adjacent endothermic channel, channel gap size, and wall thickness in steady-state ignition via inlet preheating and resistive heating, are studied. The results show that the heat loss/transfer has the largest effect on ignition for both ignition modes. For an adiabatic reactor, the ignition inlet temperature decreases with increasing wall conductivity. The exact opposite trend is observed at high heat losses. On the other hand, in the resistive heating mode, the external power input at ignition decreases with increasing wall conductivity, irrespective of the heat losses. Lower values of the inlet velocity result in a lower required power Input for ignition. The two ignition modes are contrasted, and microreactor and multifunctional devices start-up strategies are suggested.