Fan coil actuator is responsible to control the valves in order to open and close the system’s when it’s called for heating & cooling via the thermostat. This is done by letting the water into the coils when you set your thermostat either for heating or cooling. Fan coil actuators’ failure is the most common problem when you are in no heat or no cool situations. Actuators come in a variety of types and models depending on their specifications. Fan coil actuator replacement costs can range from $250 to $500 plus HST including parts and labour. Honeywell VC4011-11& VC4011-12 is the most commonly used actuators in Toronto building fan coil systems.