Mitsubishi Electric CITY MULTI CMB-P1016V-F, Руководство по обслуживанию

Страница: 60 / 183

Four-way valve
Compressor
Accumulator
CS circuit
TH2
LPS
Heat e
(HPS)
xchanger
Outdoor heat e
xchanger
Indoor heat e
xchanger
Flo
w control
valv
e
(11) Circulating composition sensor (CS circuit)
(10) Outdoor unit heat exchanger capacity control
•
• The condensing temperature (Tc) and the evaporating temperature (Te) are calculated from OC, high
pressure (HPS), and low pressure (LPS).
• The compressor frequency, the outdoor fan, and others are controlled according to the codensing temperature (Tc)
and the evaporating temperature (Te).
• CS circuit configuration (Outline drawing)
1) Control method
PURY-P200·250
2) Control
3) Capacity control pattern
Operation mode Operation pattern
Solenoid valve
SV3
ON
ON
OFF
OFF
OFF
OFF
ON
ON
OFF
OFF
OFF
OFF
OFF
ON
ON
ON
ON
OFF
ON
SV6
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
ON
OFF
OFF
OFF
ON
ON
OFF
SV5
ON
ON
ON
OFF
ON
OFF
ON
ON
ON
OFF
ON
OFF
OFF
ON
ON
ON
ON
OFF
ON
SV4
ON
ON
ON
ON
OFF
OFF
ON
ON
ON
ON
OFF
OFF
OFF
ON
ON
ON
ON
OFF
ON
1
2
3
4
5
6
1
2
3
4
5
6
8
1
1
2
7
8
1
Full cooling
Cooling mainly
Heatling mainly
Defrosting
Full heating
• In order to stabilize the evaporation temperature during cooling and the high-pressure pressure during heating that
are required in response to performance needs, the capacity of the outdoor heat exchanger is controlled by
regulating the fan volume of the outdoor unit by phase control and controlling the number of fans and by using the
solenoid valves to vary the number of out door heat exchangers being used.
• Fan is full operation for 5 seconds after starting.
• Outdoor unit fan stops during defrosting operations.
• Lower the fan strength upper limit to approximately 50% when performing night mode settings.
As shown in the drawing below; the CS circuit has the structure to bypass part of the gas discharged from the
compressor through the capillary tube to the suction side of the compressor, exchange heat before and after the
capillary tube,and produce two phase (gaseous and liquid) refrigerant at the capillary tube outlet. The dryness
fraction of refrigerant at the capillary tube outlet is estimated from the temperature of low pressure two phase
(gaseous and liquid) refrigerant at the capillary outlet (TH2) and the pressure (LPS) to calculate the composition of
refrigerant circulating the refrigeration cycle ( OC). In this series the high-pressure liquid refrigerant temperature is
calculated based on the high pressure and ambient air temperature values. It is found by utilizing the characteristic
that the temperature of two phase (gaseous and liquid) R407C under a specified pressure changes according to
the composition and dryness fraction (gas-liquid ratio in weight).
- 59 -