Dhw Method 2: Combination Dhw And Space Heating Using A Master Boiler And Member Boiler(S); (Master Type: Mixed) - HydroTherm HeatNet KN -6 User Information

OPTIONAL FEATURES
12. Set the HYB SENSOR = OFF. This sensor is
selectable for Method 5A only.
Now in the,
ADVANCED SETUP:DISTRIBUTED CTRL:
MASTER TYPE select DHW.
NOTE: JPS1 MUST be cut on all boilers
providing DHW.
DHW METHOD 2: Combination DHW
and Space Heating using a MASTER
Boiler and Member boiler(s)

(Master Type: MIXED)

This Method works much the same as DHW METHOD 1,
but also has the ability to provide space heating. The Master
boiler will use two PID controls to simultaneously maintain
the DHW and space heating setpoints. This method is
determined by ADVANCED SETUP: DISTRIBUTED
CTRL: MASTER TYPE: MIXED.
This method utilizes a 10k thermistor connected to the
DHW Sensor input and HEADER sensor input of a
MASTER boiler. Setting up the DHW portion of this
method is done via the menus in: SETUP: DOMESTIC
HOT WATER. For information on setting up the space
heating portion of this method, Refer to Heat Demand
Control Method 1 located in the CONTROL METHODS
section.
Main Heating Loop
Master Header
HS
Sensor
HS = Hydraulic separator
LOCAL
LOCAL
DHW
DHW
MASTER
OR OVR
Parallel Stat
Inputs from tanks
RIB
using RIB relays.
Example: Mixed DHW/Space Heating Simplified
Drawing
When this method is used, the OR OVR input functions as
an enable/disable. This allows the DHW heating function to
DHW Heating Loop
MEMBER
Master DHW
Sensor
DHW TANK 1
HS
be enabled or disabled much in the same way as the Heat
Demand input for space heating.
The DHW pump is individually controlled on each boiler
that fires in DHW. The Master does not use its pump
globally when any DHW boiler is called. The Master only
engages its DHW pump if it was called to perform DHW
heating.
When using this method, a DHW band is also available by
scrolling through the status screens. Press the DOWN arrow
key when SYSTEM SET is displayed. The space heating
band will be displayed on the left and the DHW Heating
band on the right. The bands will operate in a split screen
view.
When using MASTER TYPE: MIXED, The Master may
control DHW and Space Heating needs. If the Master goes
down or loses communication with the Member, a Failsafe
mode is available to provide temporary heat.
The DHW Failsafe mode is active when a Member boiler's
SETUP:AUX FUNTIONS:FAILSAFE MODES:H-NET
COMM LOST: is set to ON. When this is set to on, normal
DHW heating using the OR OVR or DHW sensor is disabled,
even though there may be a DHW call on one of these inputs.
When the Master Boiler's communication is lost, and after
10 minutes of not being restored, the DHW inputs become
active. The boiler now enters a stand-alone mode. The Heat
Demand on that boiler becomes active and not only runs to
provide failsafe space heating, but DHW heat as well. The
STATUS screen will display an ‗*' and H-NET LOST. If a
thermostat is used, the boiler will run to Method 5A until the
thermostat input removes the DHW call. If a DHW
temperature sensor is used, the boiler will modulate to
maintain tank temperature. The DHW Call always has priority
over space heating. A dual 10k sensor is available that can be
wired from one tank to two boilers.
LOCAL
DHW TANK 2
MASTER
Ensure that the Member boiler's Damper and System pump
control are configured correctly with the assumption that the
Master is not powered. Also ensure that any other System settings
related to outside air temperature sensing and system interlocks
are set to provide safe operation.
Example: Failsafe Sensor Simplified Drawing
The above example uses (2) boilers. The Master controls the
Space and Domestic needs. Failsafe control is provided by
wiring the Member boiler to the tank sensor (dual sensor is
optional) and any other system control needs the Member
HeatNet Control V3 2.x
Main Heating Loop
LOCAL
Tank Sensor 1
MEMBER
DHW
Tank Sensor 2
DHW TANK
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