Gree CAS12HP230V1AC Installation Manual page 16

INSTALLATION OF FRESH AIR VENTILATION (24,000 Btuh Size Only)
The 24,000 Btuh Ceiling Cassette can be used for fresh air ventilation.
1. Location the pre-punched knockouts hole for ventilation duct on ceiling cassette unit. Do not
remove the knock out and open hole at this point.
2. Using Fig. 38, Remove the factory installed insulation on the outside of ceiling cassette where the
pre-punched knockouts was located.
3. Remove the pre-punched knockouts and open the ventilation duct hole. Refer to Fig. 38. Be
careful not to damage internal parts such as the heat exchanger coil.
4. Install field supplied ductwork. Recommended ductwork is either an insulated flex duct, or
insulated sheet metal duct suitable for working temperatures up to 140 deg F (60 deg C).
CAUTION
Ventilated air must not exceed 10%of the total airflow or problems with operation will result.
5. Use a field-supplied power ventilation fan to increase airflow to meet job requirements. Follow the
manufacturer's installation instructions provided with the power ventilation kit.
6. Install a field supplied air filter to prevent dust and dirt from entering the ceiling cassette unit and
fouling indoor coil.
7. Install a field supplied mechanical duct damper to close during shutdown periods.
8. All metal ductwork should be covered with insulation to prevent condensation forming.
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