Meier Supply Company, Inc.                                                                        HVACR Specialists
 
 

Meier Supply Co., Refrigeration Tip: Distributors.

 
 


Refrigerant Distributors

Feed equal amounts of refrigerant through each circuit.

Refrigerant distributors are used on any DX evaporator where multiple circuits are needed to eliminate excessive pressure drops through the evaporator.  The distributor's sole purpose is to feed equal amounts of refrigerant through each circuit.

A solid column of liquid, supplied from the condenser or receiver to the expansion valve, flashes into vapor resulting in a mixture at the valve outlet.  The liquid tends to move slower than the vapor and gravity will also have an effect, separating the mixture into layers.  Without a distributor some of the evaporator circuits may receive different quantities of refrigerant, vapor, or liquid, causing inefficiencies and other problems.

The distributor adds a second pressure drop just after the expansion before the circuits, creating increased velocity and turbulence of the refrigerant allowing equal portions of refrigerant into each circuit.  The distributor and distributor tubes typically compensate for over 20% of the total pressure drop required for the low side of the system and therefore, must be considered when sizing the system expansion valve.

Typically supplied by the original equipment manufacturer, evaporator coil distributors allow for more efficiency by evenly distributing the refrigerant and increasing the effective surface area of the evaporator.