Midea MHC-V6W/D2N8-B Engineering Data

M thermal Mono
76 202005
Midea M thermal Mono Engineering Data Book
When using non-copper metallic piping, be sure to insulate the two kind of materials from each other to prevent
galvanic corrosion.
For copper is a soft material, use appropriate tools for connecting the water circuit. Inappropriate tools will cause
damage to the pipes
3.4 Water Circuit Anti-freeze Protection
Ice formation can cause damage to the hydronic system. As the outdoor unit may be exposed to sub-zero temperatures,
care must be taken to prevent freezing of the system. All internal hydronic parts are insulated to reduce heat loss.
Insulation must also be added to the field piping.
The software contains special functions using the heat pump to protect the entire system against freezing.
When the temperature of the water flow in the system drops to a certain value, the unit will heat the water, either
using the heat pump, the electric heating tap, or the backup heater. The freeze protection function will turn off only
when the temperature increases to a certain value.
In event of a power failure, the above features would not protect the unit from freezing.
Since a power failure could happen when the unit is unattended, the supplier recommends use anti-freeze fluid to
the water system.
Depending on the expected lowest outdoor temperature, make sure the water system is filled with a concentration
of glycol as mentioned in the table below. When glycol is added to the system, the performance of the unit will be
affected. The correction factor of the unit capacity, flow rate and pressure drop of the system is listed in the table
3-3.2 and 3-3.3.
Table 3-3.2: Ethylene Glycol
Concentration
of ethylene
glycol (%)
Modification coefficient
Freezing point (°C)
Cooling capacity
Power input
Water resistance
Water flow
0
1.000
1.000
1.000
1.000
0
10
0.984
0.998
1.118
1.019
-4
20
0.973
0.995
1.268
1.051
-9
30
0.965
0.992
1.482
1.092
-16
40
0.960
0.989
1.791
1.145
-23
50
0.950
0.983
2.100
1.200
-37
Table 3-3.3: Propylene Glycol
Concentration
of propylene
glycol (%)
Modification coefficient
Freezing point (°C)
Cooling capacity
Power input
Water resistance
Water flow
0
1.000
1.000
1.000
1.000
0
10
0.976
0.996
1.071
1.000
-3
20
0.961
0.992
1.189
1.016
-7
30
0.948
0.988
1.380
1.034
-13
40
0.938
0.984
1.728
1.078
-22
50
0.925
0.975
2.150
1.125
-35
Uninhibited glycol will turn acidic under the influence of oxygen. This process is accelerated by presence of copper and at
higher temperatures. The acidic uninhibited glycol attacks metal surfaces and forms galvanic corrosion cells that cause
severe damage to the system. It is of extreme importance:
That the water treatment is correctly executed by a qualified water specialist.
That a glycol with corrosion inhibitors is selected to counteract acids formed by the oxidation of glycols.
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Midea MHC-V6W/D2N8-B Specifications

General

Brand	Midea
Model	MHC-V6W/D2N8-B
Category	Air Conditioner
Language	English