How many type Expansion valve we use in Air conditioning?

Thermostatic exp valve

capillary tube

float expansion

orifice 

electrical exp valve

there are five expansion valve

The expansion valve is a passive orifice, through which the liquidrefrigerant is forced by the pressure difference between thecondensing and evaporating conditions. Capacity ratings are givenin the catalogues of manufacturers and suppliers. Types in generaluse are:

1. Capillary tubes, for small hermetic systems. These are factoryselected and cannot be adjusted.

2. Solenoid valves with liquid level sensors or liquid level valves formost flooded evaporators.

3. High-pressure float valves plus handset throttle valves for someflooded and low-pressure receiver circuits.

4. Thermostatic expansion valves or electronic expansion valvesfor most dry expansion circuits.Troubles arise with the selection of thermostatic expansion valves,since this is the type generally used in custom-built systems and, forthese, selected outside a factory.

1. expansion valve
2. capillary tube
3. thermostatic expansion valve
4. orifice type expansion valve in chillers only
5. float expansion valves
6. electrical expansion valve