MULTISTACK
1065 Maple Ave PO Box 510
Sparta, WI 54656
Service
Bulletin
Number: 1-012
Date: 1/9/2012
Topic: Head Pressure Control for Air Cooled Splits
On any air cooled split modules shipped as of 1/1/2012 the “LAC” head pressure control
valve (or valves) have been replaced by an electronic stepper “CDS “ valve along with a
fixed “ORD” valve. Both valves are shipped loose with the module and need to be field
installed. Each circuit will have 1 “CDS” valve and 1 “ORD” valve. The “CDS” needs to
be wired back to the valve control panel on the module. A schrader needs to be installed
in the discharge line and the (supplied) discharge transducer installed on and wired back
to the control panel as well. The “CDS” valve should be located in the liquid line within
10’ of the Valve Control Panel. The HP transducer and cable should also be installed
within this distance. The “ORD” Valve should go between the discharge line and the
inlet to the receiver on the liquid line. The “ORD” Valve should go between the “CDS”
valve outlet and receiver inlet. For wiring of the “CDS” valve and HP Transducer please
see the module wiring diagrams supplied with the submittal or service manual.
CDS Valve
ORD Valve
Valve Control Panel with EVD Board
HP Transducer and cable
PHONE: (608) 366-2400 ▌▌▌FAX: (608) 366-2450
MULTISTACK
1065 Maple Ave PO Box 510
Sparta, WI 54656
Service
Bulletin
Display for EVD Board
Parts supplied by MS and Factory Installed: Compressor, Evaporator, TXV, Sight Glass, Solenoid
Valve, Drier, Receiver.
Part supplied by MS and field installed: Condenser, CDS Valve, ORD Valve,
Parts not supplied but recommended: Liquid and Discharge Isolation valves at module to system
piping connections (not shown in flow diagram)
Setting Up Valve
The setting for the CDS Valve are set up in the EVD board at the Valve Control Panel
prior to shipment. 1 Display for the EVD board is provided for all modules. To modify
settings the Display will need to be connected to each EVD. The settings can be uploaded
and saved into the Display and then downloaded to the next board or settings can be
manually adjusted. The full parameter listings as well as instruction for upload and
download are available from Multistack if needed.
For any questions on this issue please contact Multistack Service / Product Support
Department at 608-366-2400.
PHONE: (608) 366-2400 ▌▌▌FAX: (608) 366-2450
Remote Air Cooled Condenser Application
EVD Evolution Twin for Sporlan CDS Valves Controller Setpoints
Configuration
Network Address
198
Refrigerant
R410A
Valve
user defined
3
Probe S1
user defined
Main Regulation EPR back pressure
4
Probe S2
not used
Auxiliary Regulation
user defined
5
Probe S3
user defined
Relay Configuration
disabled
6
Probe S4
not used
DI2 Configuration regulation start/stop
7
Display Main Var. 1 S1 Probe Measurem
Display Main Var. 2 S3 Probe Measurem
8
S1 Probe Alarm Manag. valve @ fixed pos.
S2 Probe Alarm Manag.
no action
9
S3 Probe Alarm Manag. valve @ fixed pos.
S4 Probe Alarm Manag.
no action
10
Unity Measure Imperial (°F, psig)
DI1 Configuration regulation start/stop
11
Language
English
Probes
1
S1 calibrat offset
0 psi
S1 calibrat gain on 4-20mA
1.0
2
S1 pressure MINIMUM value
0 psi
S1 pressure MAXIMUM value
653 psi
3
S1 alarm MIN pressure
0 psi
S1 alarm MAX pressure
653 psi
4
S2 calibrat offset
0 °F
S2 calibrat gain on 0-10V
1.0
5
S2 alarm MIN temperat
-58.0 °F
S2 alarm MAX temperat
221 °F
6
S3 calibrat offset
0 psi
S3 calibrat gain on 4-20mA
1.0
7
S3 pressure MINIMUM value
0 psi
S3 pressure MAXIMUM value
653 psi
8
S3 alarm MIN pressure
0 psi
S3 alarm MAX pressure
653 psi
9
S4 calibrat offset
0 °F
S4 alarm MIN temperat
-58.0 °F
S4 alarm MAX temperat
221 °F
Regulation
1
Superheat setpoint
--Valve opening at start-up
10%
2
Valve opened in stand-by
1
start-up delay after defrost
--Pre-position time 6 s (not adjustable)
Press "Help" and "<-" to Switch Between Valves A & B
1
2
Regulation continued
Hotgas bypass temp setpoint
--Hotgas bypass press setpoint
--EPR pressure setpoint
300 psi
4
PID proport gain
415
PID intergral time
150 s
PID derivative time
5.0 s
5
LowSH protect threshold
--LowSH protect intergral time
--6
LOP protection threshold
--LOP protection intergral time
--7
MOP protection threshold
--MOP protection integral time
--8
Enable manual valve position
0
Manual valve position
0 stp
9
Discharge SH setpoint
--Discharge temp setpoint
--Advanced
1
High Tcond threshold
--High Tcond integral time
--2
Modul thermost setpoint
--Modul thermost differential
--Modul thermost Shset offset
--3
CO2 regul 'A' coefficient
--CO2 regul 'B' coefficient
--4
Start manual tuning
0
Tuning method
0
Network settings
2
5
Power supply mode
0
Alarm Config
1
Low superheat alarm timeout
300 s
Low evap temp alarm timeout
300 s
High evap temp alarm timeout
600 s
2 High cond temp alarm timeout
--Low suct temp alarm thresh
-58.0 °F
Low suct temp alarm timeout
300 s
Valve
1
EEV minimum steps
200 stp
EEV maximum steps
6386 stp
EEV closing steps
6500 stp
2
EEV nominal step rate
400 Hz
EEV nominal current
210 mA
EEV holding current
20 mA
3
EEV duty cycle
70%
EEV opening synchroniz.
0
EEV closing synchroniz.
1
Multistack Part # BOARD131
Press "Prg" Button and Enter 0066 for Password
3