Toshiba Carrier RAV-SP180AT2-UL Service Manual page 43

10. Defrost control
1) In heating operation, defrost operation is performed when TE sensor satisfies any condition in A zone to
D zone.
2) During defrosting operation, it finishes if TE sensor continued 53.6°F (12°C) or higher for 3 seconds or
continued 44.6°F (7°C) ≤ TE < 53.6°F (12°C) for 1 minute.
The defrost operation also finishes when it continued for 10 minutes even if TE sensor temperature was
44.6°F (7°C) or lower.
3) After defrost operation was reset, the compressor stopped for approx. 40 seconds and then the heating
operation starts.
Start of heating operation
TE ˚F (˚C)
28.4 (–2)
23.0 (–5)
14.0 (–10)
–9.4 (–23)
∗ The minimum TE value and To value between 10 and 15 minutes after heating operation has started
are stored in memory as TE0 and To0, respectively.
When status (TE0 – TE) – (To0 – To) ≥ 37.4°F (3°C)
A zone
When status (TE0 – TE) – (To0 – To) ≥ 35.6°F (2°C)
B zone
C zone
D zone When compressor operation status of TE < 28.4°F (–2°C) is calculated by d portion
4) The time of above d can be changed by
exchanging jumper [J805] and [J806] of the
outdoor control P.C. board.
(Setting at shipment: 150 minutes)
0 10 15
∗
In normal To
continued for 20 seconds
continued for 20 seconds
When status (TE ≤ –9.4°F (–23°C)) continued for 20 seconds
39 45
B zone B zone B zone
C zone C zone C zone
When status (TE0 – TE) ≥ 37.4°F (3°C)
continued for 20 seconds
When status (TE0 – TE) ≥ 35.6°F (2°C)
continued for 20 seconds
J805
×
×
– 43 –
[min.]
55 d
A zone A zone A zone
D zone D zone D zone
In abnormal To
J806 d
150 minutes
Setting at shipment
×
90 minutes
60 minutes
×
30 minutes
: Short circuit,
×
: Open