Installation and Commissioning Guide
Package Commercial Unit
43
Installation and Commissioning Guide - Package Commercial Unit
Doc. Part No. 0525-055 Ver. 9 220308
Checking for Superheat:
Maintaining the correct superheat is important for ensuring the evaporator is achieving maximum capacity and avoiding
excessive liquid refrigerant returning to the compressor.
1. From the R-410A Pressure/Temperature Chart record the corresponding Saturated Suction Temperature (
SST
) at the
given suction pressure.
2. Calculate the system superheat using the formula below:
Superheat = SLT -SST
3. If superheat is within the range (see charging table below), there is no need to add/remove refrigerant.
●
If superheat is lower than minimum, it means that liquid refrigerant may be returning to compressor. It is
necessary to remove refrigerant.
●
If superheat is higher than maximum, it means that refrigeration capability of evaporator is not fully maximised.
It is necessary to add refrigerant charge. Allow the systems to stabilise (15-30 mins) and repeat the step 1-3 until
superheat falls within the range specified in the table below:
Models
COOLING
HEATING
Subcooling
Superheat
Subcooling
Superheat
PCG153U/V
6 - 8
4 - 6
8 -14
4 - 8
PCG173U/V
PCG203U/V
PCG233U/V
PCG260U/V
PCG290U/V
PCG290L/R
PCA300U/V
PCG300L/R
PKA300T - L/R
PCA330U/V
PCG330U/V
PCG330L/R
PCA340U/V
PCG340U/V
PCG340L/R
PCG400U
PCG400L/R
NOTES
The above subcooling and superheat recommendations are based on the following rated conditions:
• Cooling: 35°C DB outdoor, air entering indoor at 27°C DB / 19°C WB.
• Heating: 7°C DB / 6°C WB outdoor, air entering indoor at 20°C DB Nominal indoor airflow.
