Payne PG8JVA, Руководство по установке

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on the A/C selection shown in Fig. 58. The electronic
air cleaner terminal EAC--1 is energized with 115 vac
when the blower motor BLWM is operating.
When the thermostat is satisfied, the R--to--G--and--Y
circuits are opened. The outdoor unit will stop, and the
furnace blower motor BLWM will continue operating
at cooling airflow for an additional 90 seconds. Jump-
er Y/Y2 to DHUM to reduce the cooling off--delay to
5 seconds. (See Fig. 26.)
b. Single--Stage Thermostat and Two--Speed Cooling
(Adaptive Mode)
--
See Fig. 34 for thermostat connections.
This furnace can operate a two--speed cooling unit
with a single--stage thermostat because the furnace
control CPU includes a programmed adaptive se-
quence of controlled operation, which selects low--
cooling or high--cooling operation. This selection is
based upon the stored history of the length of previous
cooling period of the single--stage thermostat.
NOTE : The air conditioning relay disable jumper ACRDJ must
be connected to enable the adaptive cooling mode in response to
a call for cooling. (See Fig. 26.) When ACRDJ is in place the
furnace control CPU can turn on the air conditioning relay ACR
to energize the Y/Y2 terminal and switch the outdoor unit to
high--cooling.
The furnace control CPU can start up the cooling unit in either
low-- or high--cooling. If starting up in low--cooling, the furnace
control CPU determines the low--cooling on--time (from 0 to 20
minutes) which is permitted before switching to high--cooling. If
the power is interrupted, the stored history is erased and the
furnace control CPU will select low--cooling for up to 20 minutes
and then energize the air conditioning relay ACR to energize the
Y/Y2 terminal and switch the outdoor unit to high--cooling, as
long as the thermostat continues to call for cooling. Subsequent
selection is based on stored history of the thermostat cycle times.
The wall thermostat “calls for cooling”, closing the
R--to--G--and--Y circuits. The R--to--Y1 circuit starts the outdoor
unit on low--cooling speed, and the R--to--G--and--Y1 circuits
starts the furnace blower motor BLWM at low--cooling airflow
which is the true on--board CF selection as shown in Fig. 58.
If the furnace control CPU switches from low--cooling to
high--cooling, the furnace control CPU will energize the air
conditioning relay ACR. When the air conditioning relay ACR is
energized the R--to--Y1--and--Y2 circuits switch the outdoor unit
to high--cooling speed, and the R--to--G--and--Y1--and--Y/Y2
circuits transition the furnace blower motor BLWM to
high--cooling airflow. High--cooling airflow is based on the A/C
selection shown in Fig. 58.
NOTE : When transitioning from low--cooling to high--cooling
the outdoor unit compressor will shut down for 1 minute while
the furnace blower motor BLWM transitions to run at
high--cooling airflow.
The electronic air cleaner terminal EAC--1 is energized with 115
vac whenever the blower motor BLWM is operating.
When the thermostat is satisfied, the R--to--G--and--Y circuit are
opened. The outdoor unit stops, and the furnace blower BLWM
and electronic air cleaner terminal EAC--1 will remain energized
for an additional 90 seconds. Jumper Y1 to DHUM to reduce the
cooling off--delay to 5 seconds. (See Fig. 26.)
c. Two--Stage Thermostat and Two--Speed Cooling
See Fig. 33 for thermostat connections
NOTE : The air conditioning relay disable jumper ACRDJ must
be disconnected to allow thermostat control of the outdoor unit
staging. (See Fig. 26.)
The thermostat closes the R--to--G--and--Y1 circuits for
low--cooling or closes the R--to--G--and--Y1--and--Y2 circuits for
high--cooling. The R--to--Y1 circuit starts the outdoor unit on
low--cooling speed, and the R--to--G--and--Y1 circuit starts the
furnace blower motor BLWM at low--cooling airflow which is the
true on--board CF (continuous fan) selection as shown in Fig. 56.
The R--to--Y1--and--Y2 circuits start the outdoor unit on
high--cooling speed, and the R--to-- G--and--Y/Y2 circuits start the
furnace blower motor BLWM at high--cooling airflow.
High--cooling airflow is based on the A/C (air conditioning)
selection shown in Fig. 58.
The electronic air cleaner terminal EAC--1 is energized with 115
vac whenever the blower motor BLWM is operating.
When the thermostat is satisfied, the R--to--G--and--Y1 or R--to--
G--and--Y1--and--Y2 circuits are opened. The outdoor unit stops,
and the furnace blower BLWM and electronic air cleaner terminal
EAC--1 will remain energized for an additional 90 seconds.
Jumper Y1 to DHUM to reduce the cooling off--delay to 5
seconds. (See Fig. 26.)
4. Dehumidification Mode
See Fig. 27--29 for thermostat connections.
The dehumidification output, DHUM on the humidity
sensing thermostat should be connected to the furnace
control thermostat terminal DHUM. When there is a dehu-
midify demand, the DHUM input is activated, which
means 24 vac signal is removed from the DHUM input
terminal. In other words, the DHUM input logic is re-
versed. The DHUM input is turned ON when no dehumid-
ify demand exists. Once 24 vac is detected by the furnace
control on the DHUM input, the furnace control operates
in dehumidification mode. If the DHUM input is low for
more than 48 hours, the furnace control reverts back to
non--dehumidification mode.
The cooling operation described in item 3. above also ap-
plies to operation with a humidity sensing thermostat. The
exceptions are listed below:
a. Low cooling --When the R--to--G--and--Y1 circuit is
closed and there is a demand for dehumidification, the
furnace blower motor BLWM will drop the blower
airflow to 86 percent of low--cooling airflow which is
the true on--board CF (continuous fan) selection as
shown in Fig. 56.
b. High cooling --When the R--to--G--and Y/Y2 circuit is
closed and there is a demand for dehumidification, the
furnace blower motor BLWM will drop the blower
airflow to 86 percent of high--cooling airflow. High--
cooling airflow is based on the A/C (air conditioning)
selection shown in Fig. 56.
c. Cooling off--delay --When the “call for cooling” is
satisfied and there is a demand for dehumidification,
the cooling blower--off delay is decreased from 90
seconds to 5 seconds.
5. Super--Dehumidify Mode
Super--Dehumidify mode can only be entered if the fur-
nace control is in the dehumidification mode and there is a
demand for dehumidification. The cooling operation de-
scribed in item 3. above also applies to operation with a
humidity sensing thermostat. The exceptions are listed be-
low:
a. When the R--to--Y1 circuit is closed, R--to--G circuit is
open, and there is a demand for dehumidification, the
furnace blower motor BLWM will drop the blower
airflow to 65 percent of low--cooling airflow for a
maximum of 10 minutes each cooling cycle or until
the R--to--G circuit closes or the demand for dehumidi-
fication is satisfied. Low--cooling airflow is the true
on--board CF (continuous fan) selection as shown in
Fig. 58.
b. When the R--to--Y/Y2 circuit is closed, R--to--G circuit
is open, and there is a demand for dehumidification,
PG
8M
VA