Electronic Function; Abbreviation; Display Function; Main Protection - Midea CTBU-09HWFN1-M Service Manual

14. Electronic Function

14.1 Abbreviation

T1: Indoor room temperature
T2: Coil temperature of indoor heat exchanger
middle.
T2B: Coil temperature of indoor heat exchanger
outlet.
T3: Coil temperature of condenser
T4: Outdoor ambient temperature
T5: Compressor discharge temperature
Td: Target temperature

14.2 Display function

14.2.1 Icon explanation on indoor display board
(A5 Duct)
PRE-DEF indicator(cooling and heating type)
or fan only indicator(cooling only type)
Timer indicator
Operation lamp
Temporary button
OPERATION TIMER DEF./FAN ALARM
MANUAL
14.2.2 Icon explanation on indoor display board
(Compact cassette).
14.2.3 Icon explanation on indoor display board
(slim Cassette).
14.2.3 Icon explanation on indoor display board
(Console).
14.2.1 Icon explanation on indoor display board
(Ceiling Floor)
Alarm indicator
Infrared signal receiver
Display digital tube

14.3 Main Protection

14.3.1 Three minutes delay at restart for
compressor
1 minute delay for the 1
minutes delay for others.
14.3.2
compressor top
The unit will stop working when the compressor
top temp. protector cut off, and will restart after
the compressor top temp. protector restart.
14.3.3
compressor discharge
When the compressor discharge temp. is
getting higher, the running frequency will be
limited as below rules:
---Compressor discharge temp. T5>115 ℃
(239° F ) for 5s, compressor stops and restarts
up till T5<90℃(194° F )
---110<T5<115 ℃ (239° F ) ,
frequency to the lower level every 2 minutes.
---105(221° F ) <T5<110℃(230° F ) , keep running
at the current frequency.
----T5<105℃(221° F ) , no limit for frequency.
14.3.4 Fan speed malfunction
When indoor fan speed keeps too low (lower
than 300RPM) for 50s, the indoor fan will shut
off and restart 30s later, if protection happened
80
st
time stand-up and 3
Temperature protection
Temperature protection
of
of
decrease the