Method of pre-heating internal combustion engine uses variable choke resistance line in parallel with bypass valve to enable choked flow through latent heat store for higher coolant temp.

摘要

The method involves passing coolant through a latent heat store (L) for higher coolant temp. and bypassing it for lower coolant temp. A circulation pump (P) is switched on before starting the engine to pre-heat the engine using the heat in the latent heat store. A connecting line (3) with a variable choke resistance is connected in parallel with a bypass valve (905w) to enable a choked flow through the latent heat store for a higher coolant temp. or closed bypass valve, so that the residual or greater part of the coolant is fed via a bypass line (2) and non-return valve together with the coolant passing through the latent heat store back into the coolant circuit.