4.1.1.4. relay three Operation: Aquastat Operation
Relay Three can also be operated in Aquastat Mode, identical to the Space Heating
Function for Relay Two. Check the ‘Aquastat Operation’ button to enable this function.
FUNCTION DESCRIPTION
DEFAULT
SETTINg LIMIT
The temperature the selected sensor must exhibit to turn R3 ON. If this temperature is less
than the R3 OFF temp, R3 will be ON in between the OFF and ON temp; otherwise, it will be
ON above the R3 ON temp, and turn back off at the R3 OFF temp
160°F
50°F
≤
V
≤
200°F
The temperature the selected sensor must exhibit to turn R3 OFF. See above if R3 OFF >
R3 ON.
150°F
50°F
≤
V
≤
200°F
The installed sensor for reading the ON and OFF values set above.
T2
T1
≤
v
≤
T7
Select any thermostat channel as an extra condition for operation of R3. E.g. turn on R3
only if the temperature conditions set above AND a selected thermostat is active. Leave
unchecked for temperature condition only.
No
Channels
Active
Any or all
channels active
4.1.1.5. relay three Operation: Simple Differential Operation
Relay Three can be operated using a secondary differential with a high limit, and
optionally function conditionally based on the Solar differential or another sensor.
FUNCTION DESCRIPTION
DEFAULT
SETTINg LIMIT
HOT temperature sensor for the differential equation (
Δ
T=Hot Sensor - Cold Sensor)
T1
T1
≤
V
≤
T7
COLD temperature sensor for the differential equation (
Δ
T=Hot Sensor - Cold Sensor)
T2
T1
≤
V
≤
T7
The minimum Differential (
Δ
T=Hot Sensor - Cold Sensor) to turn Relay 3 ON from OFF
18°F
2°F
≤
V
≤
100°F
During Relay 3 operation, the maximum Differential the system can exhibit in order for Relay
3 to turn back OFF
5°F
0°F
≤
V < On Diff.
The limit Value COLD sensor at which R3 will turn OFF even with a satisfactory differential.
NOT TO BE RELIED UPON AS A SAFETY LIMIT OR PRIMARY LIMIT CONTROL.
160°F
80°F
≤
V
≤
200°F
Check this box to use the R3 high limit function
ON
ON / OFF
Choose this option to operate Simple Differential only when the Solar Relay is ON
Choose this option to operate Simple Differential only when the Solar Relay is OFF due to
the Solar Tank greater than the high limit value (T2 or the Average of T2 & T3 if installed
and Use Average is selected)
Choose this option to operate Simple Differential when the selected sensor is hotter or colder
than the set temperature.
T1, 160
°
F
T1
≤
v
≤
T7
50°F
≤
V
≤
200°F
Choose this option to operate Simple Differential all the time
4.1.2. SENSOrS AND MEtErING Bar
4.1.2.0. System Metering Box
The Delta-T Pro can be fitted with many different inputs above the normal temperature
sensors, including an electronic pressure sensor, pyranometer or current transformers.
In addition, the energy calculation algorithm can be adjusted for the installed parameters.
METER DESCRIPTION
DEFAULT
SETTINg LIMIT
Select if a grundfos VFS flow and temperature sensor is installed
ON
ON / OFF
Set the flow Range for the grundfos VFS; this is the flow range in LPM. HPAK / HFLO
Pro and HCOM’s have the default’s preset. If a sensor is purchased separately, the
range is printed on the packaging.
HPAK/HFLO 2-40
HCOM 20 - 400
MIN: 2-40
MAX: 20-400
Select if using a square wave pulse flow meter (turbine / paddlewheel)
OFF
ON / OFF
When using a pulse flow meter, set the slope of the reading curve, in Pulses / gallon.
This information will be provided with the pulse meter.
0.0
500.0
Set which flow meter reading will be used in the System Energy Calculation
grundfos VFS
VFS or Pulse
Select which sensor will be used for the HOT sensor in the System Energy Calculation.
FOR gREATEST ACCURACY, SELECT TWO SENSORS OF THE SAME TYPE (I.E.
Thermistors T1-T5, or grundfos T6 & T7)
T1
T1
≤
v
≤
T7
Select which sensor will be used for the COLD sensor in the System Energy Calculation.
FOR gREATEST ACCURACY, SELECT TWO SENSORS OF THE SAME TYPE (I.E.
Thermistors T1-T5, or grundfos T6 & T7)
T6
T1
≤
v
≤
T7
Select whether a grundfos RPS pressure sensor is installed (0 - 150PSI)
OFF
ON / OFF
CHanGInG ConTRolleR oPeRaTIon seTTInGs
14
160
150
FIg. 4.1.1.4
FIg. 4.1.1.5
FIg. 4.1.2 A
