Daikin RXYSQ6T8VB - Refrigerant Piping Length and Height Difference

5 Preparation
Installer and user reference guide
14
RXYSQ4~6T8V/YB
VRV IV-S system air conditioner
4P482277-1 – 2017.04
Refnet joints at other branches
For refnet joints other than the first branch, select the proper branch
kit model based on the total capacity index of all indoor units
connected after the refrigerant branch. Example: Refnet joint
B‑1→C‑1.
Indoor unit capacity index Refrigerant branch kit
<182 KHRQ22M20T
Refnet headers
Concerning refnet headers, choose from the following table in
accordance with the total capacity of all the indoor units connected
below the refnet header.
Indoor unit capacity index Refrigerant branch kit
<182 KHRQ22M29H
INFORMATION
Maximum 8 branches can be connected to a header.
5.3.5 Refrigerant piping length and height difference
The piping lengths and height differences must comply with the following requirements. Two patterns will be discussed:
• Outdoor with 100% VRVDX indoor units
• Outdoor with 100% RADX indoor units
Requirement Limit
VRVDX RADX
Maximum actual piping length
▪ Example 1.1, unit8: a+b+c+d+e+f+g+p≤Limit
▪ Example 1.2, unit6: a+b+h≤Limit
▪ Example 1.2, unit8: a+i+k≤Limit
▪ Example 1.3, unit8: a+i≤Limit
▪ Example 2, unit18: a+b+m≤Limit
120m 65m
Maximum equivalent piping length
(a)
150m 85m
Maximum total piping length
▪ Example 1.1: a+b+c+d+e+f+g+h+i+j+k+l+m+n+p≤Limit
▪ Example 2: a+b+c+d+e+f+g+h+i+j+k+l+m≤Limit
300m 140m
Minimum length outdoor-first refrigerant branch kit
▪ Example 2: Limit≤a
N/A 5m
Maximum length first branch kit-indoor unit
▪ Example 1.1, unit8: b+c+d+e+f+g+p≤Limit
▪ Example 1.2, unit6: b+h≤Limit
▪ Example 1.2, unit8: i+k≤Limit
▪ Example 1.3, unit8: i≤Limit
▪ Example 2, unit18: b+m≤Limit
40m 40m
Maximum length outdoor-BP
▪ Example 2, BP3: a+b≤Limit
N/A 55m
Minimum and maximum length BP-indoor
▪ Example 2, unit 18: Min.≤m≤Max.
Indoor unit capacity index<60 N/A 2~15m
Indoor unit capacity index=60 N/A 2~12m
Indoor unit capacity index=71 N/A 2~8m
Maximum height difference outdoor-indoor Outdoor higher than indoor
▪ Examples: H1≤Limit
50m 30m
Outdoor lower than indoor 40m
Maximum height difference indoor-indoor
▪ Examples: H2≤Limit
15m 15m
Maximum height difference outdoor-BP
▪ Example 2: H3≤Limit
N/A 30m
Maximum height difference BP-BP
▪ Example 2: H4≤Limit
N/A 15m
Maximum height difference BP-indoor
▪ Example 2: H5≤Limit
N/A 5m
(a) Assume equivalent piping length of refnet joint=0.5m and refnet header=1m (for calculation purposes of equivalent piping length, not for
refrigerant charge calculations).