The Purpose of a Water Flow Switch in Central Air Conditioning

A flow switch operates by conveying a trip motion (relay, reed switch, paddle) to another machine within the system, usually a pump. The trip signal will indicate to the pump to turn on or turn off.  It is necessary to provide damage protection and circuit cooling or adjust flow rates that are too high or too low.

Flow switch is a device that monitors the flow of air, steam or liquid. It sends a "trip signal" to a different device in the system, such as a pump. The flow switch can indicate to the pump to shut off or to turn on. Some of the general uses are for pump protection, for cooling-circuit protection and alarms for too high or too low flow rates.

GE-315 Adjustable Paddle Flow Switches

The GE-315 Series Paddle Water Flow Switch is a new design, adopt micro switch 5A 250V max, stabili...

Proper water flow is the necessary guarantee for the reliable operation of central air conditioning host. Improper water flow may cause the evaporator of water chiller to freeze, high condensation pressure, compressor "bite" and other failures. Therefore, appropriate water flow detection method is an important guarantee to avoid the failure of air conditioning host. In view of the importance of water flow detection, considering the maintenance cost of users in the future, many projects have begun to require the selection of the type of water flow switch.

Liquid flow switches can be used for air conditioning, hot water space heating systems, pump systems, water cooled equipment, blending or additive systems, liquid transfer systems, fire sprinkler systems, water treatment systems, swimming pool chlorination and industrial laser coolant systems. Air flow switches can be used for clean room filter systems, duct type heating, exhaust ventilating, air supply systems and air treatment systems.

GE-511A Differential Pressure Flow Switches to detect the water flow of pump

The necessity of water flow detection of central air conditioning system water flow detection of central air conditioning system is the premise and guarantee to ensure the normal operation of the refrigeration system. First of all, the central air conditioning system is to ensure the reliable heat exchange of the heat exchanger by taking the cooling capacity and heat away from the flowing water. Without water flow, there is no so-called refrigeration or heating. Secondly, when there is no water flow or water flow is small, for the evaporator, the load of the evaporator is reduced, and the evaporation temperature is reduced. If the compressor operates continuously, the evaporator will freeze.

If the evaporator can't be protected from freezing in time, the evaporator may expand and crack, causing the water side and the refrigerant side of the refrigeration system to collude, and the whole refrigeration system will be scrapped. In addition, if the water flow of the system is too low, the return pressure will be too low for a long time, and the lubricating oil discharged from the compressor will not return to the compressor smoothly, which may cause the compressor to "bite the cylinder". When there is no water flow or the water flow is small, for the condenser, the temperature and pressure of condensation rise, resulting in the flow of refrigerant at the outlet of the condenser through the expansion valve greatly reduced, and the cooling capacity decreased.