Section Iv- Charging; Vi-Maintenance - Lennox KGA Series Service Literature

8-Flame Sensing
Flame current is an electrical current which passes from the
ignition control through the sensor electrode during unit op­
eration. The current passes from the sensor through the
flame to the ground electrode (located on the flame elec­
trode) to complete a safety circuit. The electrodes should be
located so the tips are at least 1/2" (12.7 mm) inside the
flame envelope. Do not bend electrodes. To measure flame
current, follow the procedure on the following page:
NOTE - Electrodes are not field-adjustable. Any al­
terations to the electrode may create a hazardous
condition that can cause property or personal injury.
1- Disconnect power to unit.
2- Remove lead from sensing electrode and install a
0-50DC microamp meter in series between the sens­
ing electrode and the sensing lead.
3- Reconnect power and adjust thermostat for
heating demand.
4- When flame is established, microamp reading
should be 0.5 to 1.0. Do not bend electrodes.
Dropout signal is .09 or less.
5- Disconnect power to unit before disconnecting meter.
Make sure sensor wire is securely reconnected
before reconnecting power to unit.
NOTE-If the meter scale reads 0, the leads are re­
versed. Disconnect power and reconnect leads for
proper polarity.
B-Cooling System Service Checks
KGA units are factory-charged and require no further adjust­
ment; however, charge should be checked periodically using
the approach method. The approach method compares actual
liquid temperature with the outdoor ambient temperature. See

section IV- CHARGING.

NOTE - When unit is properly charged, discharge line pres­
sures should approximate those in tables 7 through 10.

VI-MAINTENANCE

The unit should be inspected once a year by a qualified ser­
vice technician.
!
WARNING
Electric shock hazard. Can cause
injury or death. Before attempting to
perform any service or maintenance,
turn the electrical power to unit OFF
at disconnect switch(es). Unit may
have multiple power supplies.
CAUTION
Label all wires prior to disconnection when servicing
controls. Wiring errors can cause improper and dan­
gerous operation. Verify proper operation after ser­
vicing.
WARNING
Product contains fiberglass wool.
Disturbing the insulation in this product during
installation, maintenance, or repair will expose you
to fiberglass wool. Breathing this may cause lung
cancer. (Fiberglass wool is known to the State of Cali­
fornia to cause cancer.)
Fiberglass wool may also cause respiratory, skin and
eye irritation.
To reduce exposure to this substance or for further
information, consult material safety data sheets
available from address shown on unit nameplate or
contact your supervisor.
IMPORTANT
The Clean Air Act of 1990 bans the intentional vent­
ing of refrigerant (CFC's and HCFC's) as of July 1,
1992. Approved methods of recovery, recycling or re­
claiming must be followed. Fines and/or incarcera­
tion may be levied for non-compliance.
A-Filters
Units are equipped with four 20 X 25 X 2" filters. Filters
should be checked and replaced when necessary with fil­
ters of like kind and size. Take note of air flow direction
marking on filter frame when reinstalling filters. See figure
21. Filters must be U.L.C. certified or equivalent for use in
Canada.
B-Lubrication
All motors are lubricated at the factory. No further lubrica­
tion is required.
REMOVE FILTERS
C-Evaporator Coil
Inspect and clean coil at beginning of each cooling season.
Clean using mild detergent or commercial coil cleanser.
Flush coil and condensate drain with water taking care not to
get insulation, filters and return air ducts wet.
Page 29
PULL TO
REMOVE
FILTERS
FIGURE 21