Mitsubishi Electric CITY MULTI PEFY Series, Technical And Service Manual

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[
VII
Troubleshooting ]
- 22 -
HWE1804A GB
7. Selecting external static pressure
This indoor unit supports three external static pressure settings.
Notes:
 When the static pressure setting were set from the remote controller, the actual setting and the switch setting on the control
board may not match because the latest setting from the remote controller overrides the previous setting. To check the latest
static pressure setting, check them on the remote controller, not on the switch.
 If the static pressure setting for the duct is lower than that for the unit, the fan of the unit may repeat start/stop, and the outdoor
unit may remain in a stopped state. Match the static pressure settings for the unit to that for the duct.
To set the static pressure setting with the switches on the control board
To set the static pressure setting from the function selection screen on the remote controller (Some remote control-
lers do not support the function selection function. Refer to the Instruction Book of a given remote controller.)
Follow the instructions below and the instructions detailed in the remote controller manual for how to set the switches.
1. Set the function setting No. 32 (Switch setting/Function selection) to “2”.
2. Set the function setting No. 8 to appropriate values, according to the airflow mode and the static pressure setting.
8. Enabling the function to prevent cold draft (during heating operation)
This indoor unit features a function that automatically changes the fan speed to Very Low when the outside temperature reach-
es at or below the preset temperature to reduce the undesired effect of cold outside air to the supply air. This function can be
enabled or disabled and the trigger threshold temperature can also be selected by setting the function No. 117 to the desired
setting. Refer to the table below for details.
External static pressure SW21-1 SW21-2 Set the switches on the control board
(SW21-1, and SW21-2) as shown in the table at left.
0.6 in.WG (150 Pa) OFF ON
0.8 in.WG (200 Pa) OFF OFF
1.0 in.WG (250 Pa) ON OFF
Selection
Function
setting No.
Initial
Setting
Current
setting
No. 32
Switch setting 1 ○
Function selection 2
External static
pressure setting
Function setting No.
Initial
setting
Current
setting
[Important]
Be sure to write down the settings for all func-
tions in the “Current setting” row if any of the
initial settings has been changed.
No. 8
0.6 in.WG (150 Pa) 1
0.8 in.WG (200 Pa) 2 ○
1.0 in.WG (250 Pa) 3
Function setting No.
Setting
Initial
setting
Current
setting
[Important]
Be sure to write down
the settings for all func-
tions in the “Current
setting” row if any of
the initial settings has
been changed.
No. 117
1 Disabled
2 Triggered at outside temperature of 23°F (-5°C) or below
3 Triggered at outside temperature of 21.2°F (-6°C) or below
4 Triggered at outside temperature of 19.4°F (-7°C) or below
5 Triggered at outside temperature of 17.6°F (-8°C) or below
6 Triggered at outside temperature of 15.8°F (-9°C) or below
7 Triggered at outside temperature of 14°F (-10°C) or below ○
15 Initialize the setting