Compressor Pi Control - Daikin FCQ18PVJU Service Manual

SiUS28-902_a
2.2

Compressor PI Control

Compressor PI Control
Carries out the compressor capacity PI control to maintain Te at constant during cooling
operation and Tc at constant during heating operation to ensure stable unit performance.
[Cooling operation]
Controls compressor capacity to adjust Te to
achieve target value (TeS).
Te setting (Set in Set-up mode 2)
37.5
[Heating operation]
Controls compressor capacity to adjust Tc to
achieve target value (TcS).
Tc setting
109.5
RZQ18 · 24 · 30P
∗ Compressors may operate in a pattern other than those listed
in above tables subject to the operating conditions.
Function
L M (Normal) H
(factory
setting)
43 48
L M (Normal) H
(factory
setting)
115 120
STEP
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Te : Low pressure equivalent saturation temperature
(°F)
TeS : Target Te value
(Varies depending on Te setting, operating
frequency, etc.)
Tc : High pressure equivalent saturation temperature
(°F)
TcS : Target Tc value
(Varies depending on Tc setting, operating
frequency, etc.)
INV.
52Hz
57Hz
62Hz
68Hz
74Hz
81Hz
88Hz
96Hz
104Hz
110Hz
116Hz
124Hz
133Hz
143Hz
158Hz
165Hz
177Hz
Basic Control
18