CONTROL METHODS
HeatNet Control V3
Page 47
DHW Method 4b: Space Heating with DHW Override of Setpoint on Master,
using a DHW 10K Tank Sensor
Example: DHW Method 4b: Space Heating with DHW Override of Setpoint on Master, using a DHW Sensor, Primary
Secondary, Reverse Return.
MASTER
MEMBER
2
MEMBER
3
HNET
Lo
ca
l P
u
m
p
HNET
DH
W
P
u
m
p
DHW Pump
Tank Sensor
Lo
ca
l P
u
m
p
Su
p
p
ly
H
ea
d
er
Se
n
so
r
Sy
st
em
P
u
m
p
Cold Water
Makeup
Ex
p
an
si
o
n
T
an
k
Ball Valve
Pressure
Reducing
Backflow
Prevention
Sy
st
em
R
e
tu
rn
Se
n
so
r
HeatNet
HeatNet
HeatNet
Domestic
Supply
Cold Water
Make Up
Domestic
Supply
Cold Water
Make Up
WM
Water Meter
MIN 3X PIPE DIAMETERS
MAX 10X PIPE DIAMETERS
BETWEEN CENTERS (TYP)
System Return
Sensor
System Header Sensor
Lo
ca
l P
u
m
p
System
Pump
System
Supply
System
Return
DHW METHOD 4b: Space Heating with DHW Override of Setpoint on Master, using a DHW Sensor, Primary
Secondary, Reverse Return
In DHW METHOD 4b, the Master’s
Heat Demand
input enables space heating by energizing the system pump and maintaining
the Heating Setpoint at the Master’s System Header Sensor. The Master’s
OR OVR
input is jumped to enable DHW heating using
the DHW tank sensor. When the DHW tank temperature drops, a DHW heat demand is generated, and the system loop
temperature is overridden with the DHW Setpoint. They system pump continues to run, and the DHW pump is enabled to supply
heat to the tanks until the DHW tank is satisfied.
Boilers are staged to meet the active setpoint based on their runtime, and each boiler will enable its local pump when it is running.
The Master modulates the boilers in order to maintain the active setpoint.
