Mitsubishi Electric PUHY-200YMF-B Service Handbook page 67

2) Control of refrigerant amount
Cooling
(a) Prohibition of liquid level detection
• Liquid level is detected in normal conditions except for the following:
For 6 minutes after starting unit, and during unit stopping.
(b) In case AL=2 is detected for 3 consecutive minutes during liquid level detection (control at excessive refrigerant
replenishment and trouble mode)
• Changed to intermittent fault check mode preceded by 3 minutes restart prevention. But it is not abnormal when
the discharge SH is high. Error stop is observed when trouble is detected again in the same intermittent fault
check mode (for 30 minutes after unit stops for intermittent fault check).
• When turning on liquid level trouble ignore switch (SW2-6), error stop is not observed, and 3 minutes restart
prevention by intermittent fault check mode is repeated. However, LED displays overflow.
(Turning SW2-6 on makes the error of TH6 < outdoor air sensor > ineffective.)
(c) When operation mode shows "Stop," excessive or insufficient refrigerant display and excessive or insufficient
refrigerant ignore display are extinguished.
Heating
(a) Prohibition of liquid level detection
Liquid level is detected in normal conditions except for the following.
• For 6 minutes after starting unit, and during unit stopping (including restart after overflow ignored).
• During defrosting operations and for 6 minutes after defrosting.
(b) In case AL=2 is detected for 3 consecutive minutes during liquid level detection (control at excessive refrigerant
replenishment and trouble mode)
• Changed to intermittent fault check mode preceded by 3 minutes restart prohibition. But it is not abnormal when
the discharge SH is high. Error stop is observed when trouble is detected again in the same intermittent fault
check mode (for 30 minutes after unit stops for intermittent fault check).
• When turning on liquid level trouble ignore switch (SW2-6), error stop is not observed, and 3 minutes restart
prevention by intermittent fault check mode is repeated. However, LED displays overflow.
(Turning SW2-6 on makes the error of TH6 < outdoor air sensor > ineffective.)
Ps
* Judgement by the AL is at best only a
rough guideline.
Please do not add refrigerant based on
the AL reading alone.
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