Toshiba MMU-P0121H Service Manual page 71

Check code
[89]
Indoor over capacity
Is backup of outdoor unit
being completed?
NO
Is No.of connected
indoor units acceptable? (
YES
Is set up of indoor unit
horse power correct?
YES
Is total capacity of connected
indoor units within 135%?
YES
Check IPDU P.C. board.
( 1) Set up no detection of over capacity
*
Turn on SW09 bit 2 on interface P.C. board of outdoor unit. (Usually OFF)
( * 2) Check No. of connected indoor units.
Set SW01/SW02/SW03 on interface P.C. board of outdoor unit to 1/4/3, respectively.
No. of connected units is displayed on the 7 segment display.
Check code
Outdoor unit backup operation prohibited
If there is a unit which is setting backup operation of the outdoor unit, heating operation cannot be performed.
( * 1)
( 1) Outdoor unit backup operation set up
*
When both SW06 Bit 1 and 2 on the interface P.C. board of the master outdoor unit are ON (Usually
both are off.)
1. No. of connected indoor units/connected over capacity
2. Incorrect set up of indoor unit horse power
YES
NO
2)
*
NO
NO
[8C]
Operation cause
Indoor unit over capacity was
detected during outdoor unit backup
set up.Set no detection of over
capacity. (
Outdoor units of other system
excessively connected.
Modify miswiring.
Keep capacity of connected indoor
units within 135%.
Backup set up of outdoor unit
3-68
1)
*
Modify set up of horse power.
Operation cause