Page 57
XP21 SERIES
SunSource
®
Home Energy System
This Dave Lennox
Signature
®
Collection heat pump is
factory−equipped with components that make it
SunSource
®
solar−ready. These units can be matched
with solar modules and other optional equipment so that
they can become part of a SunSource
®
Home Energy
System.
Units can be upgraded for use with solar equipment at the
time of installation or in the future.
Solar energy is first used to meet cooling/heating
demands. When the outdoor unit is not operating, the
system powers lighting, appliances and other electronic
devices in the home. Any surplus power is sent back to the
utility company for a possible credit (check with your local
utility company for availability).
The SolarSync
t
package consists of the following
components:
S
Lennox
®
Solar Subpanel installed in a Dave Lennox
Signature
®
Collection air conditioner or heat pump
unit.
S
Solar modules (1 to 15 may be used to vary the
amount of electricity generated).
S
Envoy Communications Gateway monitors solar
power performance.
All components must be ordered separately. See the
Lennox XP21 Engineering Handbook for SunSource
®
Home Energy System component ordering.
Wiring runs from the roof−mounted solar modules to the
outdoor unit. From there, power travels to the home
electrical service panel using the existing outdoor unit
power wiring.
Checklists
TWO
STAGE COMPRESSOR CHECKOUT
Use this check-out procedure to verify part- and full-load
capacity operation of two-stage modulation compressor.
IMPORTANT
This performance check is ONLY valid on systems that
have clean indoor and outdoor coils, proper airflow over
coils, and correct system refrigerant charge. All
components in the system must be functioning proper to
correctly perform compressor modulation operational
check. (Accurate measurements are critical to this test
as indoor system loading and outdoor ambient can affect
variations between low and high capacity readings).
TOOLS REQUIRED
S
Refrigeration gauge set
S
Digital volt/amp meter
S
Electronic temperature thermometer
S
On-off toggle switch
PROCEDURE
1. Turn main power OFF to outdoor unit.
2. Adjust room thermostat set point 5ºF above (heating
operation) or 5ºF below (cooling operation) the room
temperature.
3. Remove control access panel. Install refrigeration
gauges on unit. Attach the amp meter to the common
(black wire) wire of the compressor harness. Attach
thermometer to discharge line as close as possible to
the compressor.
4. Turn toggle switch OFF. Install switch in series with Y2
wire from room thermostat (see note ** in the
Field
Operational Checklist
on page 58).
5. Cycle main power ON.
6. Allow pressures and temperatures to stabilize before
taking any measured reading (may take up to 10
minutes).
7. Record all of the readings for the Y1 demand.
8. Close switch to energize Y2 demand. Verify power is
going to compressor solenoid (see note ** in the
Field
Operational Checklist
on page 58).
9. Allow pressures and temperatures to stabilize before
taking any measured reading (this may take up to 10
minutes).
10. Record all of the readings with the Y1 and Y2 demand.
11. If temperatures and pressures change in the direction
noted in chart, the compressor is properly modulating
from low to high capacity. (If no amperage, pressures
or temperature readings change when this test is
performed, the compressor is not switching between
low and high capacity and replacement is necessary).
12. After testing is complete, return unit to original set up.
