Extended Balance Point; Condensate Overflow Safety Switch Connection (Cn4F) - Mitsubishi Electric PAAA18AA1 Installation Manual

15.8.3. Extended balance point

Some outdoor units may have the capacity to report lower outdoor temperatures, below ‑15° C (5° F). For
information about the outdoor unit's Extended Balance Point capability, refer to the respective outdoor unit
manual. The PAA (indoor) unit firmware automatically detects whether the connected outdoor unit has this
capability and adjusts the meaning of Mode 8 and Mode 10 accordingly (* see "Outdoor Unit-Extended
outdoor air temperature" in the table in the "Economic balance point" section above).

15.9. Condensate overflow safety switch connection (CN4F)

The PAA unit is equipped with a drain pan overflow detection switch and a wire harness for the CN4F
connector. The wire harness and switch must be installed before operating the unit. Otherwise the unit will
give out an error and cool mode will not run. The switch is a normally closed switch that connects to the
two wires coming from the CN4F connector supplied with the PAA unit. If the switch is open, the unit no
longer operates in Cool or Dry mode. See installation below:
N.C.
oat switch
When the Normally Closed Float
Switch opens, the Indoor unit will
turn off.
Frequently, a condensate pump is used to pump the condensate from the PAA unit to a drain installed at
a higher elevation than the PAA unit. Many condensate pumps have an overflow switch that detects if the
reservoir is about to overflow for any reason. Typically, these overflow switches are also normally closed
switches that should be wired in series with the drain pan overflow switch as in the illustration above.
Specifications are subject to change without notice.
PAA-A18, 24, 30, 36, 42AA1/BA1/CA1
93
Control Board in Control Box
Control Box
© 2022 Mitsubishi Electric US, Inc.