Operating Sequence - Lennox G61MPV Service Manual

OPERATING MODE
System Thermostat
Condition Demand
Y1
Normal operation Normal operation
Y2
Y1
Y1
Call for humidity
removal during removal during
1st−stage cooling
Demand
demand
satisfied
Y1
Y1
Significant increase in
humidity during humidity during
thermostat cooling
Y1
demand.
Y1
Humidity demand
Y1
satisfied during satisfied during
thermostat demand.
None
Y1
Y2
Call for humidity Call for humidity
removal during 2nd
Y2
stage thermostat
demand
demand
Y2
None
*Call for 1st stage
cooling after call for cooling after call for
humidity removal.
Y1
None
Call for 2nd stage
cooling after call for cooling after call for
humidity removal
Y2
None
Call for cooling after
significant increase in significant increase in
humidity
Y1 or Y2
Humidity demand
None
satisfied between satisfied between
thermostat demands
(unit off cycle).
Y1 or Y2
NOTE − When changing unit mode of operation from cooling to heating, indicating lights that are on will stay on until the first ther-
mostat heating demand.
*IMPORTANT - If power to unit is turned on with CCB1 calling for humidity removal, outdoor unit may be locked into high speed
indefinitely. To reset, move humidity slide switch all the way down then back up to desired setpoint (with unit running)
** Reduced blower speed is 49% HIGH COOL speed.
*** Reduced blower speed is 70% HIGH COOL speed.
****If the two−speed control on a two−speed outdoor unit is set for LATCH 2 (15 minutes) or LATCH 3 (30 minutes),
the compressor will latch into high speed after a Y1 demand has occurred for that period of time.
TABLE 22

OPERATING SEQUENCE

G61MPV, CCB1 and Two−Speed Outdoor Unit
SYSTEM DEMAND
*Relative Humidity
(EfficiencyPlus Lights)
No demand. Acceptable
No demand. Acceptable
No demand. Acceptable
Humidity level rises slightly
(1) above setpoint. Demand
initiated.
Humidity level remains
slightly (1) above setpoint.
Demand continues.
Humidity level remains
slightly (1) above setpoint.
Demand continues.
No demand. Acceptable
Humidity level rises signifi-
cantly (2 or more) above
setpoint. Demand initiated.
Humidity level
above setpoint.
Humidity level falls below
setpoint. No demand.
No demand. Acceptable
No demand. Acceptable
No demand. Acceptable
Humidity level rises slightly
(1) above setpoint. Demand
initiated.
No demand. Acceptable
Humidity level is slightly (1)
above setpoint.
Humidity level is slightly (1)
above setpoint.
Humidity level is slightly (1)
above setpoint.
Humidity level is slightly (1)
above setpoint.
Humidity level is significantly
above setpoint (2 or more).
Humidity level is significantly
above setpoint (2 or more).
Humidity level is slightly (1)
above setpoint.
Humidity level falls below
setpoint. No demand.
SYSTEM RESPONSE
****Compressor Blower CFM
Speed (COOL)
**49% of HIGH
Low
COOL
High HIGH COOL
**49% of HIGH
Low
COOL
**49% of HIGH
Low
COOL
Off
Off
***70%of
High
HIGH COOL
**49% of HIGH
Low
COOL
***70% of
High
HIGH COOL
***70% of
High
HIGH COOL
HIGH COOL
High
Off
Off
**49% of HIGH
Low
COOL
HIGH COOL
High
***70% of
High
HIGH COOL
HIGH COOL
High
Off
Off
**49% of HIGH
Low
COOL
Off
Off
***70% of
High
HIGH COOL
Off
Off
***70% of
High
HIGH COOL
Off
Off
HIGH COOL
High
Page 36
Comments
Compressor demand and indoor
blower speed controlled by blower speed controlled by
thermostat demand
Dehumidification mode does not begin
until after initial thermostat demand is until after initial thermostat demand is
satisfied and new cooling demand is
initiated.
If humidity rises significantly above set-
point, or if slide switch is moved signifi-
cantly, unit will immediately go into de- cantly unit will immediately go into de
humidification mode (in presence of
thermostat demand).
When humidity demand is satisfied, When humidity demand is satisfied,
blower immediately shifts to the COOL
CFM in order to hasten the end of the
cycle. Unit can only shift out of high l U it l hift t f hi h
speed compressor operation at begin- speed compressor operation at begin-
ning of next cycle.
Blower immediately changes speed in
response to thermostat demand.
Dehumidification mode (high speed
compressor) begins with next thermo- compressor) begins with next thermo-
stat demand after initial demand is sat-
isfied.
Reduced blower speed (dehumidifica-
tion speed) begins immediately with tion speed) begins immediately with
thermostat demand
If humidity increases significantly over
setpoint, or if slide switch is moved,
unit immediately goes into dehumidifi- unit immediately goes into dehumidifi
cation mode (in presence of thermostat
demand).
While unit is not operating (no thermo-
stat demand), slide switch is moved
down and back up. Blower and com- down and back up Blower and com
pressor operate at high speed until
next thermostat demand.