Lennox Merit Series 13HPX Units Installation Instructions Manual page 15

IMPORTANT
NOTE - After testing has been completed, properly reposi­
tion test jumper across desired timing pins.
DEFROST CONTROL (CMC1)
DEFROST TIMING
PINS (P1)
TEST
PINS
COMPRESSOR
DELAY PINS
REVERSING
VALVE
S87
LOW PRESSURE
SWITCH
DEFROST
THERMOSTAT (S6)
S4
HIGH PRESSURE
SWITCH
FIGURE 17
Service Light Connection
The defrost control includes terminal connections for a
service light which provides a signal that activates the room
thermostat service light during periods of inefficient
operation.
Defrost Control Diagnostic LEDs
The defrost board uses two LEDs for diagnostics. The LEDs
flash a specific sequence according to the condition.
DEFROST CONTROL (CMC1) DIAGNOSTIC LEDS
Mode Green LED (DS2)
No power to control OFF
Normal operation /
Simultaneous Slow FLASH
power to control
Anti‐short cycle
Alternating Slow FLASH
lockout
High pressure switch Slow FLASH
fault
High pressure switch ON
lockout
HIGH PRESSURE SWITCH (S4)
This unit is equipped with a high pressure switch which is
located on the liquid line. The SPST, normally closed
pressure switch opens when liquid line pressure rises above
the factory setting of 590 + 15 psig and automatically resets
at 418 + 15 psig.
DIAGNOSTIC
LEDS
24V TERMINAL
STRIP
CONNECTIONS
SERVICE LIGHT
CONNECTIONS
TABLE 4
Red LED (DS1)
OFF
OFF
OFF
Homeowners Information
Before attempting to perform any service or maintenance,
turn the electrical power to unit OFF at disconnect switch.
Cleaning of the outdoor unit's coil should be performed by a
licensed professional service technician (or equivalent).
Contact your dealer and set up a schedule (preferably twice
a year, but at least once a year) to inspect and service your
outdoor unit. The following maintenance may be performed
by the homeowner.
Sprinklers and soaker hoses should not be installed
where they could cause prolonged exposure to the
outdoor unit by treated water. Prolonged exposure of
the unit to treated water (i.e., sprinkler systems, soak­
ers, waste water, etc.) will corrode the surface of steel
and aluminum parts, diminish performance and af­
fect longevity of the unit.
The outdoor unit must be properly maintained to ensure its
proper operation.
•
Please contact your dealer to schedule proper inspection
and maintenance for your equipment.
•
Make sure no obstructions restrict airflow to the outdoor
unit.
•
Grass clippings, leaves, or shrubs crowding the unit can
cause the unit to work harder and use more energy.
•
Keep shrubbery trimmed away from the unit and
periodically check for debris which collects around the
unit.
•
Keep snow level below the louvered panels to ensure
proper performance.
Routine Maintenance
In order to ensure peak performance, your system must be
properly maintained. Clogged filters and blocked airflow
prevent your unit from operating at its most efficient level.
NOTE The filter and all access panels must be in place
—
any time the unit is in operation. If you are unsure about the
filter required for your system, call your Lennox dealer for
assistance.
1. Ask your Lennox dealer to show you where your indoor
unit's filter is located. It will be either at the indoor unit
(installed internal or external to the cabinet) or behind a
return air grille in the wall or ceiling. Check the filter
monthly and clean or replace it as needed.
2. Disposable filters should be replaced with a filter of the
same type and size.
3. The indoor evaporator coil is equipped with a drain pan
to collect condensate formed as your system removes
humidity from the inside air. Have your dealer show you
the location of the drain line and how to check for
obstructions. (This would also apply to an auxiliary
drain, if installed.)
Page 15
CAUTION
IMPORTANT !
Outdoor Coil
13HPX SERIES