An inflator including a housing with a first chamber that contains a quantity of gas generant. An initiator is operatively associated with the first chamber and in reaction initiating communication with at least a portion of the quantity of gas generant. The initiator, upon actuation, acts to ignite at least a portion of the quantity of gas generant to form gas. The housing further has a second chamber adjacently disposed to the first chamber. The second chamber contains a sealed storage reservoir and a piston assembly. The sealed storage reservoir includes a liner and a lid and contains a quantity of liquid. The piston assembly includes a piston. During deployment, the piston moves to unseal the storage reservoir to release at least a portion of the quantity of liquid such that the released liquid contacts and cools gas formed by the ignition of the gas generant. A discharge opening permits gas to exit the housing.