Carrier /50HC 04-28, Controls, Start-Up, Operation And Troubleshooting, Page: 136 / 144

136
APPENDIX D — ENERGYX ® EXHAUST FAN PERFORMANCE
Many applications that utilize energy recovery incorporate
ducted return/exhaust air paths. In these applications it is im-
portant to consider the duct pressure of the return/exhaust just
as a designer would consider the effects of the supply duct stat-
ic pressure on the airflow of the rooftop unit itself.
The exhaust fan in the Modulated Volume EnergyX unit will
assist the rooftop unit fan in pulling air through the exhaust/re-
turn duct. These exhaust fans are backwards curved impeller
designs which are capable of significant more static pressure
operation than typical forward curved fan designs. The follow-
ing exhaust fan performance curves are provided for additional
guidance when considering return/exhaust duct design.
NOTE: If application designs require two separate ducts (one for
exhaust air, one for return air) contact your Carrier Sales Engineer
for additional guidance prior to specification or ordering.
Fig. B — 3 Ton SRT Unit ERV Supply and Exhaust Fan Performance Curves
0
200
400
600
800
1000
1200
1400
0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
ECONOMIZER MODE
ERV MODE
External Static Pressure (in H
2
0)
CFM