Midea Mini VRF Service Manual

R410A All DC Inverter Mini VRF MCAC-VTSM-2016-02
52 Installation
Table 2: Indoor unit main pipes selection (L1~L5)
Total capacity of
downstream indoor units
(kW)
Main pipe size(mm)
Branch Pipe
Gas pipe
Liquid pipe
A＜16.6
Φ15.9
Φ9.53
FQZHN-01D
16.6≤A＜23
Φ19.1
Φ9.53
FQZHN-01D
Table 3: Main pipes selection (L1)
Total capacity of
outdoor units
(kW)
When the equivalent length of all liquid and air
pipes < 90m
When the equivalent length of all liquid and air
pipes ≥ 90m
gas side
(mm)
liquid side
(mm)
The first line
branch pipe
gas side
(mm)
liquid side
(mm)
The first line
branch pipe
A＜16
Φ15.9
Φ9.53
FQZHN-01D
Φ19.1
Φ9.53
FQZHN-01D
16≤A＜23
Φ19.1
Φ9.53
FQZHN-01D
Φ22.2
Φ9.53
FQZHN-02D
Note: Main pipe L1 can be selected form table 2 and table 3, the larger size should be finally selected.
The straight distance between copper pipe turning and the contiguous branch pipe is at least 0.5m.
The straight distance between the contiguous branch pipes is at least 0.5m.
The straight distance which the branch pipes connected to the indoor unit is at least 0.5m.
Table 4: Outdoor unit pipe connection
Piping side
MODEL
Outdoor unit pipe connection (mm)
Gas Side
Liquid Side
120 model
Φ15.9
Φ9.53
140 model
Φ15.9
Φ9.53
160 model
Φ19.1
Φ9.53
Outdoor Unit
Maximum Quantity of Indoor unit
Total Capacity of Indoor unit
120 model
7
45%~130%
140 model
8
45%~130%
160 model
9
45%~130%
If ODU connect more than one IDU, the capacity of each IDU should be not more than 8kW for refrigerant uniform
distribution.
When capacity of indoor unit greater than the sum of 100%, capacity of indoor unit will be attenuated.
When capacity of indoor unit greater than or equal to the sum of 120%, in order to ensure the effectiveness of
machine, and then try to open the indoor units at different time.
4.4 Remove Dirt or Water in the Piping
Make sure there is no any dirt or water before connecting the piping to the outdoor units.
Wash the piping with high pressure nitrogen, never use refrigerant of outdoor unit.
4.5 Airtight Test
Charge pressured nitrogen after connecting indoor/outdoor unit piping to do airtight test.
Cautions:
1. Pressured nitrogen [4.3MPa (44kg/cm
3
) for R410A] should be used in the airtight test.
2. Tighten high pressure/low pressure valves before applying pressured nitrogen.
3. Apply pressure from air vent mouth on the high pressure/low pressure valves.
4. The high pressure/low pressure valves are closed when applying pressured nitrogen.
5. The airtight test should never be used any oxygen, flammable gas or poisonous gas.
4.6 Vacuum
Using vacuum pump to do the vacuum and never using refrigerant to expel the air.
Vacuum should be done from both liquid side and gas side simultaneously.

Midea Mini VRF Specifications

General

Brand	Midea
Model	Mini VRF
Category	Air Conditioner
Language	English