A method of operating a control valve for controlling the exhausting of a purge gas from a fuel cell assembly, the method comprising: a) providing a control valve comprising: a valve body having: a purge gas inlet port connected to receive a purge gas from the fuel cell assembly an outlet port for providing an outlet for the purge gas, and a valve member within the valve body, moveable between a first position and a second position, wherein the valve member is configured to, in the first position, prevent purge gas from flowing between the inlet port and the outlet port and, in the second position, allow the flow of purge gas between the inlet port and the outlet port; wherein the valve member is biased to the first position such that the purge gas inlet port is normally closed by the valve member; and wherein the valve body further includes a drain port adapted and arranged in the valve body to allow liquid to drain out of the valve body, the drain port being configured to close when the valve member is in the second position; and b) operating the control valve in the first position to prevent purge gas from flowing between the inlet port and the outlet port and to allow liquid to drain out of the drain port, and in the second position, to allow the purge gas to flow between the inlet port and the outlet port and to close the drain port. a) providing a control valve comprising: a valve body having: a purge gas inlet port connected to receive a purge gas from the fuel cell assembly an outlet port for providing an outlet for the purge gas, and a valve member within the valve body, moveable between a first position and a second position, wherein the valve member is configured to, in the first position, prevent purge gas from flowing between the inlet port and the outlet port and, in the second position, allow the flow of purge gas between the inlet port and the outlet port; wherein the valve member is biased to the first position such that the purge gas inlet port is normally closed by the valve member; and wherein the valve body further includes a drain port adapted and arranged in the valve body to allow liquid to drain out of the valve body, the drain port being configured to close when the valve member is in the second position; and a valve body having: a purge gas inlet port connected to receive a purge gas from the fuel cell assembly an outlet port for providing an outlet for the purge gas, and a valve member within the valve body, moveable between a first position and a second position, wherein the valve member is configured to, in the first position, prevent purge gas from flowing between the inlet port and the outlet port and, in the second position, allow the flow of purge gas between the inlet port and the outlet port; in the first position, prevent purge gas from flowing between the inlet port and the outlet port and, in the second position, allow the flow of purge gas between the inlet port and the outlet port; wherein the valve member is biased to the first position such that the purge gas inlet port is normally closed by the valve member; and wherein the valve body further includes a drain port adapted and arranged in the valve body to allow liquid to drain out of the valve body, the drain port being configured to close when the valve member is in the second position; and b) operating the control valve in the first position to prevent purge gas from flowing between the inlet port and the outlet port and to allow liquid to drain out of the drain port, and in the second position, to allow the purge gas to flow between the inlet port and the outlet port and to close the drain port.