D-EOMHP01501-22_00EN 12/29
Unit controller switches the pump frequency on the basis of:
1.
Actual unit capacity
2.
Double Speed digital input state
If there are no active compressors (Unit Capacity = 0%) pump speed is set to
Standby Speed
, otherwise
Speed 1
is selected
depending on the
Double Speed
input state.
3.6.2. DeltaT
The third control mode is the
DeltaT
mode where the pump speed is modulated through a PID to ensure a constant difference
between Evaporator Entering Water Temperature and Evaporator Leaving Water Temperature.
This mode is regulated by following setting:
▪
Evaporator DeltaT in Cool Mode
▪
Condenser Delta T in Heat Mode
All settings related to pump management are available in the menu [8].
Menu Parameter
Range
Description
R/W Psw
08
00
(
Recirculation time
)
0-300
Minimum time required within flow switch has to be closed to allow unit
startup.
W
1
01
(
Standby Speed
)
0-100
Pump speed with Unit Capacity = 0
W
1
02
(
Evap pump Speed
)
0-100
Actual Evaporator feedback pump speed.
R
1
03
(
Max Speed
)
0-100
Maximum value for pump speed.
W
1
04
(
Min Speed
)
0-100
Minimum value for pump speed.
W
1
05
(
Sp Speed1
)
0-100
First target value for pump speed in Fixed Speed control conditions.
W
1
06
(
Parameter-K
)
1-10
This value scales the PI algorithm parameters to obtain a faster response.
W
1
07
(
Evap
Setpoint DeltaT
)
0-10
Evaporator Water Temperature difference setpoint.
W
1
08
(
Evap Delta T
)
0-10
Evaporator Delta temperature Between EWT and LWT
R
1
09
(
Evap Pump Run Hours 1
)
0-99999
Evaporator Operation Hours
R
1
10
(
Evap Pump Run Hours 2
)
0-99999
Evaporator Operation Hours
R
1
11
(
Evap Pump Mode
)
Auto/Manual
Pump mode. This parameter allows to switch the control of the pump to a
fixed speed.
W
1
12
(
Evap Manual Speed)
0-100
Manual Pump Speed. Pump speed when the manual mode is selected.
W
1
13
(
Evap
Thermo
Off
Stanby Speed
)
0-100
Pump Speed in Thermostat Off Unit condition
W
1
14
(
Cond Stanby Speed
)
0-100
Speed when there are no compressors running
W
1
15
(
Cond Pump Speed
)
0-100
Actual Condenser feedback pump speed.
R
1
16
(
Cond Max Speed
)
0-100
Maximum value for pump speed.
W
1
17
(
Cond Min Speed
)
0-100
Minimum value for pump speed.
W
1
18
(
Cond Speed 1
)
0-100
Speed when the input Speed Switch is open
W
1
19
(
Cond Parameter-K
)
0-10
This value scales the PI algorithm parameters to obtain a faster response.
W
1
20
(
Cond Setpoint DT
)
0-10
Condenser Water Temperature difference setpoint.
W
1
21
(Cond Delta T)
0-10
Condenser Delta temperature Between EWT and LWT
R
1
22
(
Cond Pump Run Hours
)
0-99999
Condenser Operation Hours
R
1
23
(C
ond Pump Mode
)
Auto/Manual
Pump mode. This parameter allows to switch the control of the pump to a
fixed speed.
W
1
24
(C
ond Manual Speed
)
0-100
Manual Pump Speed. Pump speed when the manual mode is selected.
W
1
25
(Cond
Thermo
Off
Stably Speed)
0-100
Pump Speed in Thermostat Off Unit condition
W
1
The path in the Web HMI interface for Pump Settings is
“
Main Menu à View/Set Unit à Pumps
”
.
Delta T control must have both water probes at the evaporator inlet in order to operate
. The path in the Web HMI interface
for EWT Sensor enabling is
“
Main Menu à Commission Unit à Configuration
→
Options
”
.
