Haier Smart Power Series Service Manual page 140

Flare Nut
Type-2 flare nuts instead of type-1 nuts are used to increase the strength. The size of some of the flare nuts have
also been changed.
Flare nut dimension (mm)
External dimension
Size
of pipes
Ф6.35 1/4"
Ф9.52 3/8"
Ф12.7 1/2"
Ф15.88 5/8"
Ф19.05 3/4"
• Using this table as a reference, choose pipes that meet the local standards.
• For new installations, use the standard pipe sizes. When using existing pipes, size-up is allowed as mentioned in
the table above.
Additional restrictions towards allowable pipe lengths, as mentioned in the table 7.3 on page 11, must be taken
into account.
Not using the standard pipe size may result in capacity decrease. The installer must acknowledge this and judge
this very carefully in function of the complete installation.
• Existing or pre-installed piping can be used
1. Piping must comply with the criteria below.
• Piping diameter must comply with the limitations asindicated in paragraph "7.5.2. Refrigerant pipe size" on page
120.
• Piping length must be withinlimits of the allowable pipinglength as in paragraph "7.5.3. Allowable pipe length
and height difference" on page 120.
• Piping must be designed for R410A. See paragraph "7.4.2. Selection of piping material" on page118.
2. Piping can be reused without cleaning when:
• Total 1-way piping length:<50m.
• No compressor breakdown has occurred in the history of the unit to be replaced.
• A correct pump down operation can be executed:
- Operate the unit continuously for 30minutes in cooling mode.
- Execute a pump down operation.
- Remove the air conditioning units to be replaced
• Check the contamination inside the existing piping.
If you cannot meet all these requirements, the existing pipes must be cleaned or replaced after removing the air
conditioning units to be replaced.
3. Prepare the flare connections for higher pressure. See paragraph 7.4.2
Cautions on handling the stem cap
• The stem cap is sealed where indicated by the arrow. Take care not to damage it.
After handling the stop valve, make sure tighten the stem cap securely. For the tightening torque, refer to the
table below. Check for refrigerant leaks after tightening the stem cap.
Dimension B
R410A (Type2) R22 (Type1)
17.0 17.0
22.0 22.0
26.0 24.0
29.0 27.0
36.0 36.0
NOTICE
138
Smart Power