Forced Function Of Oil Level Detection (Outdoor Unit) - Toshiba MMU-P0121H Service Manual

3-9. FORCED FUNCTION OF OIL LEVEL DETECTION
(OUTDOOR UNIT)
The oil level detection control can be forcibly implemented by a switch on the interface P.C. board of the outdoor
unit. When an error in the oil tank circuit occurs and there is no cause such as sensor error, connection error, out
of place, valve close operation error, etc., check as follows.
<Oil tank circuit system error>
Check code Check code name
d7 Low oil level detection protection
d8 TK1 temp. detection circuit alarm
d9 TK2 temp. detection circuit alarm
db Oil level detection circuit blockage detection
dC Oil level detection circuit leakage detection
<Operation procedure>
1) Start the trial operation after alarm was cleared.
2) Set SW01/SW02/SW03 on the interface P.C. board of the outdoor unit to 1/16/1, which oil level is tobe
detected.
3) Push the push-switch SW04 for 2
seconds.
4) Check the 7 segment display on
the P.C. board.
<Oil level judgment result>
Judgment
Oil amount in the compressor is adequate. Check that the operation continues and there is no problem.
[A0]
If [dC] occurred, execute check even if oil level was judged as adequate.
Oil level was judged as shortage. If this judgment continues, the system stops in protection.
[A1]
When [d7], [dC] occurred, check according to the check items.
TK1 temp. detection was judged as an error. If this judgment continues, the system stops in protection.
[A2]
When [d8] occurred, check according to the check items.
Oil level detection circuit (SV3C valve) was judged as blockage. If this judgment continues, the system stops in protection.
[A3]
When [db] occurred, check according to the check items.
TK2 temp. detection was judged as an error. If this judgment continues, the system stops in protection.
[A4]
When [d9] occurred, check according to the check items.
<Peripheral circuits of oil tank>
Oil level shortage status has been detected continuously for approx. 2 hours
while oil equalizing control was continuously implemented.
Temp. change at the oil tank primary side was not detected while oil level
detection control was implemented.
Temp. change at the oil tank secondary side was not detected while oil level
detection control was implemented.
Temp. change at both the oil tank primary side and secondary side was not
detected while oil level detection control was implemented.
The status that TK1 temp. is high (50°C or more) was continuously detected
for a long time.
Operation starts. →
During operation. →
Oil level detection control starts. →
During oil level detection counting. →
Oil level judgment result.
TK1
SV3C valve
sensor
Strainer
Capillary
TK2
sensor
Oil
tank
Check
Oil
SV3A
valve
removal
valve
valve
Check
valve
Balancing pipe valve
Judgment
[OL] [– –]
Counted down every 10 seconds from [OL] [1F]
[OL] [FF]
Counted up every 1 second from [OL] [01]
[OL] [A0] [A1] [A2] [A3] [A4]
Judgment
Check joint
Capillary
Oil
separator
Strainer
Accumulator
Compressor
Check
valve
Strainer
3-135
7 segment display
SV3B
valve