Abstract: In the present method, cold substances are transferred through a nozzle with moving parts. An insulating boot facilitates the method. The present method is generally suited for use in transferring cryogenic substances such as during the refueling of liquid natural gas vehicles. The present method causes an insulating layer to be created between a removable boot and a nozzle separating the ambient environment from the moving parts of the nozzle, purging the layer with a dry gas such as nitrogen to remove moisture and restricting the incursion of such moisture from the layer and therefore, from the moving parts to avoid freezing up of the moving parts. The layer can also help to avoid freezing up of the abutting interface created between the nozzle and receiving line when the nozzle is removably engaged to a receiving line.