Vertiv Liebert CRV 300 CW, Product Documentation

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Application of Liebert
®
CRV
Liebert CRV - PD - 265086 - 11.01.2018
2.3.2 For A units
Outdoor temperature: lower limit -10°C
To install an air conditioner in places in which external temperature reaches very low values sometime
in the year requires some means of control to maintain adequate condensing pressures to ensure
proper liquid system operation.
With low temperatures the refrigerant condensates in pipeline and the liquid tends to fulfill the condens -
er.
It’s mandatory
to install the following components:
1. NON RETURN VALVE (liquid line)
Install a non- return valve in the liquid line directly out of the condenser. It doesn’t allow the liquid to
come back to the condenser (that means efficiency loss and dangerous stress for the compressor).
2. VARIEX FAN SPEED CONTROL
Use Variex fan speed control to regulate the condensing pressure and have a continuous and better
subcooling control.
It’s suggested
to have:
3. HORIZONTAL CONDENSER POSITION
The condenser horizontal disposition (vertical flow) is necessary to reduce subcooling variations due to
direct wind exposure. (very important to have a good subcooling control).
For all exceptions contact the Liebert
®
Sales Representative.
Outdoor temperature: higher limit
This limit is determined by coupled condenser model. In any case the max external temperature is 48°C
Exceeding of this limit (or a lack of maintenance), will caused a compressor stop by HP safety thermo -
stat. Reset to normal operation can only be carried out manually.
Remote Condenser
To ensure correct operation, best performance, and longest life the units must be connected to remote
condensers approved by Vertiv .
The warranty clauses are no longer valid if unit is connected to a not approved remote condenser.
For lenght higher than 30m condenser ove15%.
(1) For more details see User Manual
(2) Positive difference in height: condenser above conditioner. Negative difference in height: condenser below conditioner
2.3.3 For C units
Relative position room unit vs. 50 Hz remote condenser
From unit to condenser max distance equivalent length, m
(1)
100
From unit to condenser max geodetic height, m
(1) (2)
Max above 30 Max below 8
Requirements
Pipe diameter
(1)
see the User Manual
Oil traps on vertical line of gas refrigerant, m every 6
Max. water pressure 16 bar
Max. differential pressure through the closed valve: Dp
cv
Max. differential pressure across the valve for modulating service: Dp
ms
Models Dp
cv
(kPa) Dp
ms
(kPa)
CR032RC 300 300
CR038RC 300 300
CR060RC 175 175