Electra KN 24 RC, Руководство по обслуживанию

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11-6
CONTROL SYSTEM
Revision Y06-02 Service Manual - KN Series
11. 3 .5 Prote c tions
a. High pressure protection is applicable to all operating m odes.
b. Deicing control is valid in Heat and A uto Heat Modes only.
c. De f rosting control is valid in Dry, Cool, and A uto Cool Modes.
11. 3 .6 Ther m istors Oper a tion
a. Return air Te m p. is detected by R A T in nor m al Mode, or by RCT (R/C sensor) in
I-FEEL Mode.
b. Indoor Coil Te m p. is detected by ICT.
c. Outdoor Coil Te m p. is detected by OCT.
d. De f inition o f ther m istor f aults:
1) Ther m istor is disconnected - the ther m istor reading is belo w – 30
O
C.
2) Ther m istor is shorted - the ther m istor reading is above 7 5
O
C.
3) Ther m istor Te m p reading doesn’t change -
a) This test is per f or m ed only once a f ter a unit is s w itched f ro m OFF/STB Y
to operation. A t the f irst occurrence o f 10 m in continuous COMP
operation, the current ICT are co m pared w ith those w hen the COMP w as
s w itched f ro m OFF to ON 10 m in be f ore. I f the ' T is less than 3
O
C, the
ther m istor is regarded as de f ective.
b) The ICT no-change error can be disabled together by connecting a 4. 7k :
resistor (5%) to the ICT connector. These resistors are equivalent to a
ther
m istor 48+/-1
O
C.
e. Cases f or disabling ICT ther m istor disconnected detection:
1) The detection o f ther m istor f aults a. and b. above is disabled w hen Deicer
Protection is started. The detection w ill be enabled again only a f ter (1) the
deicing is co m pleted, and (2) COMP has been restarted and operated f or 30
sec.
2) When all the f ollo w ing conditions are f ul f illed:
a) 4. 7k : resistor is connected to the OCT.
b) IF A N is OFF.
c) Co m pressor is ON.
d) ICT < -30 (disconnected).