Vertiv | Liebert CRV CCD10 Condenser | User Manual
3
Overview
1.3
Introduction of Low Ambient Kit
The refrigeration system schematic diagram with Low Ambient Kit is shown in figure 1-1. The Low Ambient Kit is
consisted of receiver with electric heating belt, head pressure valve, safety valve, check valve, pressure switch, etc.
The Low Ambient Kit is designed to maintain proper operating head pressure in outdoor temperature down to -29.2
℉
（
-34
℃）
. It works by flooding the condenser coil with liquid refrigerant to a level that balances the system
condensing requirements with the condenser coil surface available to reject the system heat. During the summer, the
system requires the entire condenser coil surface for heat rejection and most of the refrigerant is stored in the receiver.
In the winter, the same amount of heat can be rejected by only a fraction of the coil surface. As head pressure begins
to fall, the control valve restricts the flow of liquid refrigerant existing from the condenser. This extra liquid refrigerant
reduces the effective condenser surface area available for heat transfer. The head pressure valve also bypasses hot gas
into the receiver to warm the liquid and maintain liquid pressure for proper operation of the expansion valve. The Low
Ambient Kit is the extension configuration of standard condenser and is field installed.
Figure 1-1 The refrigeration system schematic diagram with Low Ambient Kit
1.3.1
Liquid receiver
The liquid receiver is used to storage refrigerant liquid. The main function of the liquid receiver is to make the Low
Ambient condenser meet the demand of refrigerant for low temperature load in winter and high temperature load in
summer. There are three connection ports in the receiver, they are used to connect liquid input pipe, liquid output
pipe and safety valve, as shown in figure 1-2. In order to observe the refrigerant level in the liquid receiver
conveniently, two sight glass are installed on the receiver.
Condens
er
CRV
Outdoor
Indoor
Refrigerant flow
NRV
Head Pressure Valve
(head pressure valve to bypass the
condenser)
Liquid receiver
(with electric heater for outdoor
installations)
12.7mm(1/2in.) or 16mm(5/8in.)
According to Table 3-6 of indoor user manual
Liquid pipeline
Solenoid Valve
12.7mm(1/2in.)
Max 2m
(6.6ft.)
16mm(5/8in.) or
18mm(3/4in.)
Hot Gas pipeline
Pressure Switch
Safety Valve
