A microvalve device for controlling fluid flow in a fluid circuit (10). The microvalve device comprises a body (12) having a cavity formed therein. The body further has first (20) and second (22) pilot ports placed in fluid communication with the cavity. The body also has first (28) and second (30) primary ports placed in fluid communication with the cavity. Each port is adapted for connection with a designated fluid source. A pilot valve (36) supported by the body is movably disposed in the cavity for opening and closing the first and second pilot ports. An actuator (38) is operably coupled to the pilot valve for moving the pilot valve. A microvalve (40) is positioned by the fluid controlled by the pilot valve. The microvalve is a slider valve having a first end (40a) and a second end (40b). The slider valve is movably disposed in the cavity for movement between a first position and a second position. The first end of the slider valve is in fluid communication with the first and second pilot ports when the first and second pilot ports are open. The second end of the slider valve is in constant fluid communication with the first primary port. When moving between the first and second positions, the slider valve at least partially blocks and unblocks the second primary port for the purpose of variably restricting fluid flow between the primary ports.