(under subclass 12.1) Apparatus in which the device is provided with separate controllable through passages, leading from a source of fluid, at least one of the passages having a valving means permitting said fluid to pass directly to a point of use, regardless of the temperature existing in the system, and at least one other passage being provided with means for controlling the flow of said fluid in response to a temperature condition or a change in temperature occurring at some point in the apparatus.
