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Figure 14. Typical XPG20 Wiring
Solar Module Setup and Connections
OVERVIEW
The Lennox SunSource
t
Comfort System solar assisted
heat pump utilizes a single solar module to offset the utility
power consumed by the outdoor fan. The heart of the
SunSource is a 24VDC Electronically Commutated Motor
(ECM) that is coupled directly to the AC powered ECM
motor used in the XPG20 heat pump. This DC motor is
wired directly to the output of the single solar module.
When the solar module produces electricity and the heat
pump fan is running, the DC motor applies a torque on the
fan shaft and reduces the load of the AC motor. The AC
motor inverter control
senses
this reduction in load and
realize that the AC motor does not have to work as hard to
achieve its desired speed. Thus it reduces the power the
AC motor consumes. The more sunlight that is available
the more assist the DC motor will produce, and the less
utility power is consumed by the AC motor.
SOLAR MODULE MOUNTING AND TILT ANGLE
The solar module should be mounted in a location where it
will receive maximum sunlight throughout the year. When
choosing a site, avoid trees, buildings or obstructions
which could cast shadows on the solar module especially
during the winter months when the arc of the sun is lowest
over the horizon.
