Trane IntelliPak 2 Series Installation, Operation And Maintenance Manual page 100

U U n n i i t t S S t t a a r r t t u u p p
Frost Avoidance Setpoint. The Leaving Recovery Temp
Sensor is installed in the leaving air stream on the
exhaust-fan side of the energy wheel.
Figure 68, p. 100 provides the exhaust air temperature
setpoint for 70ºF return air at various percents of
relative humidity.
Where variable effectiveness / outside air bypass is not
enough to prevent frosting conditions, the energy
recovery wheel shuts off. Turning the wheel off during
frost conditions is a reliable method of preventing the
wheel from frosting, however, energy is not being
recovered and the extreme heating load must be
handled otherwise. Extreme winter design condition
for energy recovery units may require return air
preheat.
An energy recovery wheel proving function is also
provided to indicate when the wheel is not turning after
it has been commanded on.
Figure 69. Energy recovery wheel operation
Outside Air Intake Damper
(Mist Eliminator not shown)
Exhaust Air
Bypass Damper
100
Exhaust Air,
Leaving Energy
Recovery Wheel,
Path to Exhaust Fan
Building Return Air
Figure 68. Energy recovery wheel exhaust air
setpoint temperatures
Outside Air Bypass Damper
Energy Recovery Wheel
Conditioned Outside Air
Unit
Return
Path to Filters & Coil
Airflow
ERW Unit Entering Air
(Mixed Return Air &
Conditioned Outside Air)
Return Air Damper
RT-SVX24Q-EN