Mitsubishi Electronics PURY-P400 Refrigerant Volume, Additional Refrigerant Charge Volume

(2)Refrigerant Volume

1)Checking the Operating Condition

Operate all the indoor units in cooling or in heating, checking the discharge temperature, sub-cooling, low pressure saturation temperature, inlet temperature, shell bottom temperature, fluid level, fluid step, etc. and rendering an overall judgment.

Note:

Depending on the operating state, AL = 0 does not mean that there is insufficient refrigerant.

	Condition	Judgment
1	Discharge temperature is high. (125° C or higher)
2	Low pressure saturation temperature is extremely low.	Refrigerant volume tends toward
3	Inlet superheating is high (if normal, SH = 20 deg. or lower).
		insufficient.
4	Shell bottom temperature is high (the difference with the low pressure saturation
	temperature is 70 deg. or greater)
5	Shell temperature is low (the difference with the low pressure saturation temperature is	Refrigerant volume tends toward
	10 deg. or lower).
		overcharge.
6	Liquid level AL = 2

2)Cautions When Judging the Liquid Level

If you are judging the liquid level, be sure the liquid level sensor function (sensor and heater) are operating normally.

	Check Items				Judgment
1	Liquid Heater Disconnection Check				Normal if the resistance is 2.8 kΩ ± 7 %.
2	Liquid Heater Output Check	1 2 3 4 5 6 7	8 9 10
	Turn 1 ON on the LED monitor display switch (SW1) ON			, and output	Normal if AC 198 ~ 264 V is output
	the signal for the heater relay to LED 5, then check the	voltage of the heater terminal (AC			together with the LED lighting.
	198 ~ 264 V) (leave the heater connections as they are).
3	Use the LED monitor display to check if there is misalignment between the actual
	temperature and the detected temperature of TH2 ~ TH4.

3)Check the refrigerant volume by LED monitor display using the LED.

Set the LED monitor display switch (SW1) as shown below and check the past information (history) concerning the refrigerant volume.

1 2 3 4 5 6 7 8 9 10

Set SW1 as shown in he figure at right. ON

If LD3 lights up, it indicates the refrigerant charge abnormal delay state just before emergency stop due to refriger- ant overcharge (1500).

(3)Additional Refrigerant Charge Volume

At the time of shipping from the factory, the outdoor unit is charged with the amount of refrigerant shown in the following table, but since no extension piping is included, please carry out additional charging on-site.

Outdoor Unit Model	PURY-P400YMF-C	PURY-P500YMF-C
Refrigerant Charge Volume	20 kg	22 kg

Calculation Formula

Calculate the additional refrigerant volume by calculating the size of the extension liquid piping and its length (units: m).

Additional Refrigerant Volume	(kg) = (0.31 ⋅ L1) + (0.12 ⋅ L2) + (0.06 ⋅ L3) + (0.024 ⋅ L4) + α 1 + α 2
	(Note 1)
In the calculation results, round up fractions smaller than 0.01 kg. (Example: 18.54 kg → 18.6 kg)
(α Calculation Table)	L1: Length of ø25.4 high press pipe (m)

Total Capacity of Connected Indoor Units	α 1
161 ~ 330	2.0 kg
331 ~ 480	2.5 kg
481 ~ 630	3.0 kg
631 ~	4.0 kg
	α 2
BC controller (master) only	0 kg
BC controller (slave) connected	3.0 kg

L2: Length of ø12.7 liquid pipe (m)

L3: Length of ø9.52 liquid pipe (m)

L4: Length of ø6.35 liquid pipe (m)

α1: refer to the calculation table.

(Note 1) : In case high press pipe size (L1) is ø22.22, 0.25 ⋅ L1.

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