5)Change in number of operating indoor units while defrosting

•If the number of indoor units changes while the outdoor unit is defrosting, the defrosting operation continues. Once defrosting has ended, control for changing the number of units is performed.

•If the indoor unit is stopped while the outdoor unit is defrosting or if the thermostat is set to off, the defrosting operation continues. Once defrosting has ended, the unit is stopped.

6)Number of compressors operating during defrosting

•The number of compressors operating during defrosting is always two.

(7)Control of liquid level detecting heater

Detect refrigerant liquid level in accumulator, and heat refrigerant with liquid level heater for judging refrigerant amount. 7 steps of duty control is applied to liquid level heater depending on frequency and outdoor air temperature, 1 minute after starting compressor.

(8)Judgement and control of refrigerant amount

•Judge refrigerant amount by detecting refrigerant liquid surface in the accumulator.

1)Judgement of accumulator liquid level

•Return refrigerant from accumulator liquid level detecting circuit to compressor inlet pipe, detect piping tempera- ture, and judge liquid level.

When heated with heater, liquid refrigerant temperature is almost equal to low pressure saturation temperature, and gas refrigerant temperature is a little higher than low pressure saturation temperature. By comparing these temperatures A in accumulator inlet portion, refrigerant liquid level can be judged.

Accumulator liquid level is judged in 3 steps as shown in the figure, from temperature A and liquid level detecting temperatures (TH3, TH4). After deciding refrigerant status (Liquid: TH3 and TH4 are TH2 + 9° C or less, Gas: TH3 and TH4 are TH2 + 9° C or more), judge liquid level by comparing TH3 and TH4.

Balance pressure pipe

Inlet pipe

TH2

TH3

Dividing plate *Temperature A: low pressure saturation temperature

(TH2).

AL=2

AL=1

 

AL=0

• Judgement by the AL is at best only a

 

Outlet

rough guideline.

pipe

Please do not add refrigerant based

 

on the AL reading alone.

TH4

2)Control of liquid level detection

1 Prohibition of liquid level detection

Liquid level is detected in normal conditions except for the following; (Cooling)

•For 6 minutes after starting unit, and during unit stopping. (Heating)

•During defrosting.

•For 10 minutes after refrigerant recovery.

(Note that liquid level determination is being performed even when liquid level detection is being disregarded.)

2In 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 disreguard switch (SW2-4), error stop is not observed, and 3 minutes restart

prevention by intermittent fault check mode is repeated. However, LED displays overflow. (Turning SW2-4 on makes the error of TH6 < outdoor air sensor > ineffective.)

3When operation mode shows “Stop,” excessive or insufficient refrigerant display and excessive or insufficient refrigerant ignore display are extinguished.

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Mitsubishi Electronics P500YMF-C Control of liquid level detecting heater, Judgement and control of refrigerant amount
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PURY-P400, P500YMF-C specifications

Mitsubishi Electronics has long been a leader in the HVAC industry, known for its innovative technology and reliable performance. Among its notable offerings are the P500YMF-C and PURY-P400 models, designed to address the diverse needs of commercial and residential applications.

The Mitsubishi P500YMF-C is a high-performance outdoor unit that showcases energy efficiency and advanced refrigerant technology. It employs a sophisticated inverter-driven compressor, which optimizes energy usage by adjusting its speed based on the specific heating and cooling demands of the environment. This flexibility helps to minimize energy consumption while ensuring optimal comfort.

One of the standout features of the P500YMF-C is its ability to provide consistent heating and cooling even in extreme outdoor temperatures. The unit can operate effectively in low-temperature conditions, making it ideal for regions with harsh winters. Furthermore, the system is designed with a robust build, ensuring durability and longevity.

On the other hand, the PURY-P400 is an indoor multi-split system that complements the outdoor unit perfectly. It's designed for versatility and efficiency, capable of accommodating multiple indoor units connected to a single outdoor unit. This feature is particularly beneficial for larger spaces or buildings where different zones require individual climate control.

The PURY-P400 incorporates Mitsubishi's advanced filtration technology, which significantly improves indoor air quality. It features a multi-layer filtration system that effectively removes dust, allergens, and other particulates from the air, ensuring a healthier environment for occupants.

Both systems utilize R-32 refrigerant, which has a lower global warming potential compared to traditional refrigerants. This not only makes them more eco-friendly but also complies with emerging environmental regulations. The ease of installation and operation of these units is another noteworthy characteristic, with intuitive controls and user-friendly interfaces that facilitate seamless integration into existing systems.

In summary, the Mitsubishi P500YMF-C and PURY-P400 represent a fusion of technology, efficiency, and user-centric design. With a range of features aimed at enhancing performance and environmental sustainability, these models are an excellent choice for anyone looking to invest in a reliable and efficient HVAC system. Whether for residential or commercial use, Mitsubishi’s offerings continue to set the standard in comfort and efficiency.
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