Amana ANX, Обслуживание и устранение неисправностей

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SYSTEM OPERATION
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1.1 On a demand for cooling, the room thermostat
energizes “G” and “Y1” and 24Vac is supplied to “G” and
“Ylow/Y1” of the MBE/AEPF unit. The VSTB inside the
MBE/AEPF will turn on the blower motor and the motor
will ramp up to 60% of the speed programmed in the
motor based on the settings for dip switch 5 and 6. The
VSTB will supply 24Vac to “Ylow/Y1” at the condenser and
the compressor and condenser fan starts in low speed
operation.
1.2 If first stage cooling cannot satisfy the demand, the
room thermostat will energize “Y2” and supply 24Vac to
the MBE/AEPF unit. The blower motor will change to the
cfm for high speed operation and the VSTB will supply
24Vac to “Y/Y2” at the condenser and the compressor and
condenser fan will change to high speed operation. When
the “Y2” demand is satisfied, the thermostat will remove the
“Y2” demand and the VSTB will remove the 24Vac from “Y/
Y2” at the condenser.
The blower will drop to 60% of the programmed cfm and
the compressor and condenser fan will change to low
speed. On most digital/electronic thermostats, “Y2”
will remain energized until the first stage cooling
demand “Y1” is satisfied and then the “G”, “Y1” and
“Y2” demands will be removed.
1.3 When the first stage cooling demand, “Y1”, is satisfied,
the room thermostat removes the 24Vac from “G” and “Y1”.
The MBE/AEPF removes the 24Vac from “Ylow/Y1’ at the
condenser and the compressor and condenser fan are
turned off. The blower motor will ramp down to a complete
stop based on the time and rate programmed in the motor.
2.0 Heating Operation
2.1 On a demand for heat, the room thermostat energizes
“W1” and 24Vac is supplied to terminal “E/W1” of the
VSTB inside the MBE/AEPF unit. The VSTB will turn
on the blower motor and the motor will ramp up to the
speed programmed in the motor based on the settings for
dip switch 1 and 2. The VSTB will supply 24Vac to heat
sequencer HR1 on the electric heater assembly.
2.2 HR1 contacts M1 and M2 will close within 10 to 20
seconds and turn on heater element #1. At the same time,
if the heater assembly contains a second heater element,
HR1 will contain a second set of contacts, M3 and M4,
which will close and turn on heater element #2.
NOTE: If more than two heater elements are on
the heater assembly, it will contain a second heat
sequencer, HR2, which will control the 3rd and 4th
heater elements if available. For the 3rd and 4th
heater elements to operate on a second stage heat
demand, the PJ4 jumper on the VSTB inside the MBE/
AEPF must be cut. With the PJ4 jumper cut, the VSTB
will run the blower motor on low speed on a “W1”
only demand. If the first stage heat demand, “W1”
cannot be satisfied by the heat pump, the temperature
indoors will continue to drop. The room thermostat
will then energize “W2” and 24Vac will be supplied
to HR2 on the heater assembly and the blower motor
will change to high speed. When the “W2” demand is
satisfied, the room thermostat will remove the 24Vac
from “W2” and the VSTB will remove the 24Vac from
HR2. The contacts on HR2 will open between 30 to 70
seconds and heater elements #3 and #4 will be turned
off and the blower motor will change to low speed. On
most digital/electronic thermostats, “W2” will remain
energized until the first stage demand “W1” is satisfied
and then the “W1” and “W2” demands will be removed.
2.3 When the “W1” heat demand is satisfied, the room
thermostat will remove the 24Vac from “E/W1” and the
VSTB removes the 24Vac from HR1. The contacts on
HR1 will open between 30 to 70 seconds and turn off the
heater element(s) and the blower motor ramps down to a
complete stop.
MBE/AEPF With Two Stage ASZ & DSZ Heat Pump
Units
3.0 Cooling Operation
When used with the ASZ & DSZ two stage heat pumps,
dip switch #4 must be set to the OFF position on
the VSTB inside the MBE/AEPF. The “Y1” output from
the indoor thermostat must be connected to the purple
wire labeled “Ylow/Y1” inside the wire bundle marked
“Thermostat” and the purple wire labeled “Ylow/Y1” inside
the wire bundle marked “Outdoor Unit” must be connected
to “Y” at the heat pump. The “Y2” output from the indoor
thermostat must be connected to the yellow wire labeled
“Y/Y2” inside the wire bundle marked “Thermostat” and the
yellow wire labeled “Y/Y2” inside the wire bundle marked
“Outdoor Unit” must be connected to “Y/Y2” at the heat
pump. The orange jumper wire from terminal “Y1” to
terminal “O” on the VSTB inside the MBE/AEPF must
be removed.
On heat pump units, when the room thermostat is set to
the cooling mode, 24Vac is supplied to terminal “O” of the
VSTB inside the MBE unit. The VSTB will supply 24Vac to
“O” at the heat pump to energize the reversing valve. As
long as the thermostat is set for cooling, the reversing valve
will be in the energized position for cooling.