Friedrich MRM09Y1J, Service & Parts Manual

Page: 31 / 135

31 PB
OPERATION
9-12k Sequence of Operation
(1)Cooling Mode
(2) Dry Mode
1. When room temperature set point is <-3.6°F , cooling will stop;
Outdoor fan will stop later and indoor fan will operate at set
speed;
2. When room temperature set point is 3.6°F
for a period of time, cooling operation will be started.
In that case, indoor fan, outdoor fan and compressor
will operate and the indoor fan will operate at set speed.
* In this mode, fan and swing motor will operate at set status
and the temperature range setting is 61~86°F.
* If there is malfunction of outdoor unit or the unit stops for
protection, the indoor unit will keep its operation status but the
error will be displayed.
(3) Fan Mode
1. In this mode, the fan motor runs at low fan speed while swing
works according to setting state. The range of setting temperature
is 61~86°F.
2. When outdoor unit has malfunction or stopped for protection,
the indoor fan will keep the original running state and the error will
be displayed.
(4) Heat Mode
1. In this mode, the indoor fan may run at high, medium, low and
automatic speed. The compressor, outdoor fan and 4-way valve all
stop running.
2. In this mode, the range of setting temperature is 61~86°F.
1.Heating mode
When setting temperature-indoor temperature≤ 84.7°F.the unit will
stop heating. Both outdoor fan and indoor fan will stop later.
When setting temperature-indoor temperature>84.7°F and it lasts
for a certain period, the unit will start heating. In that case, indoor
fan, outdoor fan and compressor will start running. The indoor fan
works according to the anti-cold air.
* In this mode, the range of setting temperature is 61~86°F.
2.Protection function: in heating mode, when the compressor stops
as a result of malfunction, the indoor fan blows residual heat.
3.Defrosting control: when the defrosting signal is received, defrosting
C
B
e
Code H1 will be shown. Theindoor fan stops.
*Anti-cold air function
The rotational speed of indoor electromotor is decided based on
the indoor pipe temperature. The indoor fan can run at low speed
or stop running if neccesary to maintain operation This function will terminate
after the unit runs for 3min or the pipe temperature reached certain value.
During heating, if the indoor pipe temperature is lower than certain
value.The speed of the indoor fan will decrease automatically
based on the pipe temperature and ensures that the outlet air is warm.
During heating, when the setpoint condition for the indoor unit is
reached,the compressor and the outdoor fan motor stop running
In this mode, the system selects the operation mode (cooling and
fan) automatically according to the ambient temperature. The
display shows the actual operation mode and setting temperature.
function is the same as that of other modes:
1. When T
2. For cooling only unit: when T
amb.
mode.
indoor amb.
enter auto mode and run in automatic fan mode. If the other mode
changes to auto mode, the previous operation mode will remain.
(6)Auto fan speed Mode
In auto fan mode, the rotational speed of the fan for indoor unit
is decided by the differential temperature between ambient
temperature and set temperature. In dry mode, the automatic fan
speed is forced to be low.
C
B
Cooling
operation
Cooling
operation
With compressor capacity supplied
With no compressor capacity supplied
type
Mode
High
Turbo fan
speed
Medium
fan
speed
fan
speed
during cooling
during heating
during cooling
during heating
(7) Louver Control
and the air deflectors will rotate upward. The indoor fan will stop
after one minute.
Ther will be a 30 second delay for mode conversion. The protection
The air outlet will