The damper could be stuck closed, preventing cold air from flowing into the fresh food section. Rarely, there could be an electrical issue with the control board (which sends voltages to components that need to be turned on or off) or the thermistor (which monitors the temperature and reports...
however. Many systems use a valve to control the rate of flow through the fluid through the piston, rather than alter the properties of the liquid itself. The more restricted the flow, the firmer the stroke of the damper’s piston.