Specifications

Eliminated Parts

The Master-Bilt Reverse cycle’s unique technology, coupled with the bi-flow electric expansion valve, eliminates the

need for:

• Defrost heaters

• Head pressure control valves

• Check valves and expansion valves at the condenser that are normally necessary in traditional hot gas

defrost systems

• By-pass valves

• Liquid line solenoid valves

• Receiver tanks (except in B-series condensing units 6 HP and up)

• Sight glasses

Removing these components reduces the cost of the evaporator itself and saves on installation and wiring.

Defrost Time

Defrost time is greatly lessened with the reverse cycle option. The average time using electric defrost heaters is 20-

30 minutes but reverse cycle performs a completely “clean” defrost typically in 3 – 5 minutes for freezers and 1

– 2

minutes for coolers. Because the defrost is so rapid, there is no noticeable increase in freezer room temperature and

the product temperature rise is also significantly less. Reverse cycle defrost, combined with demand defrost,

assures the evaporator receives the number of complete defrosts needed at the necessary times to prevent iced

evaporators while assuring the protection of the valued product being stored.

Charging a Master Controller 2.0 System Equipped with Reverse Cycle

Defrost

Note: If you are a first time installer of a Master Controller 2.0 system,

please call Master-Bilt for on-phone training.

Please refer to Page 21: Charging the Master Controller 2.0 Refrigeration System

Due to the reversing of the refrigerant flow, it is recommended that the refrigeration liquid line piping also

be insulated to prevent condensation drips between the condensing unit and the evaporator coil.

ELECTRIC WIRING

WARNING

Please make sure to turn all power off before servicing electrical equipment. Always use a qualified and

trained technician. If you are the technician and a first-time installer of a Master Controller 2.0 system, call

our service department at 800-684-8988 for free training and support.

The field wiring for a Master Controller 2.0 refrigeration system includes the power supply to the condensing

unit, the evaporator (fans, heaters and controller) and the communication cables between master and slaves.

Thermostat wiring may be used for four-way reversing valve power supply since it is 24 VAC.