Westinghouse 9K-18K Use And Installation Instruction page 7

2.5 Mode Interfere (for multi-split, 9K&12K)
Multi-zone outdoor units can only support a single mode at one time (cooling or heating).
mode (cooling or heating). When the mode set at one or more indoor unit is different from the mode that
outdoor unit is using mode interfere will occur.
cooling dry
√ √
cooling
√ √
dry
× ×
heating
√ √
fan
Outdoor units always use the mode of the first indoor unit that started operation. When mode interfere occurs,
the unit in interference will emit 3 beeps and turn off automatically.
heating fan
× √ √ --- normal
× √ × --- mode interfere
√ ×
× √
5
Before Operation