OPTIONAL FEATURES
HeatNet Control V3 2.x
mode is active. Setting this value to
NO
leaves the
system pump on. This active period includes the post
purge of the DHW pump/valve.
19.
Select the menu item
POST PURGE.
This is the time
that the DHW pump relay remains energized after the
DHW thermostat has been satisfied. Once the tank has
opened it‟s thermostat, the system/local setpoint will be
reloaded and the post purge time will begin.
20.
Select the menu item:
LOCAL PUMP OFF:
When a
DHW heating cycle begins, what to do with the local
pump/valve is determined:
NO
The local pump/valve will remain running during
DHW heating.
YES
The local pump will shut off with a delay
determined by
LOCAL DELAY: seconds.
This
allows the DHW pump/valve to prove before
shutting off the local pump.
Piping of the system will determine which setting to
use.
21.
Select the menu item:
PURGE TO.
After a DHW cycle
completes, the pump/valve can be selected to either
purge to the
TANK
, or to the
SPACE
for the duration
of the post purge time. This selection can use the space
to dump the heat from the boiler and not overheat the
DHW tank/load.
22.
Set the
HYB SENSOR = OFF
. This sensor is
selectable for Method 5A only.
Follow the same steps as used to program DHW
Heating using a Header Sensor INPUT.
USE
SENSOR,
select
NO
.
DHW METHOD 5: DHW of a Local
Boiler’s Tank.
Method 5A using a 10k Type II tank sensor.
This method is used to provide combination space heating
and DHW heating. The boiler may be stand alone or in a
HeatNet configuration. It is meant to fire an individual
boiler in a DHW heating priority mode when that boiler‟s
local tank temperature has a call for DHW heat (tank
sensor‟s temperature drops below the DHW Se
LOWER BAND). The boiler will stop space heating (if
running) and switch to DHW heating. The DHW
pump/valve will be engaged and the water temperature in
the tank will be maintained by the boiler at the DHW
setpoint. Once the tank temperature exceeds the Se
UPPER BAND temperature, DHW heating will stop and the
pump/valve‟s post purge will start.
LOCAL DHW TANK
MEMBER
Tank Sensor
LOCAL DHW TANK
MASTER
Tank Sensor
Main Heating Loop
LOCAL
LOCAL
DHW
DHW
LOCAL DHW Simplified Drawing
When a tank‟s temperature sensor is connected directly to a
boiler and the
BOILER MODE
is set to
LOCAL.
The
boiler will go offline from HeatNet and service the DHW
needs of its local tank. If the boiler is running in space
heating mode, then the “SHARING” setting may be used to
determine how, or if, to shut down before starting a DHW
cycle. When the DHW cycle is complete (includes the post
purge time of the DHW pump), the boiler will go back
online with HeatNet and become available to fire.
During a DHW cycle the DHW setpoint will be loaded
along with the UPPER and LOWER BAND limits. Also,
the
SETTINGS: DISTRIBUTED CONTROL: MASTER
TYPE:
is set to
AUTO.
When a 10k Type II sensor is used with this method, the OR
OVR input functions as and enable/disable. This allows the
DHW heating function to be enabled or disabled much in
the same way as the Heat Demand input for space heating.
When using this method, a DHW band is also available by
in the Home Screen 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.
23.
Connect a
10k thermistor from the DHW tank‟s sensor
well to J10B terminals on any boiler. Wire a pump or
valve from the DHW pump or the System pump
(normally open) relay contact to control flow of the
heating water into the tank‟s coil or system loop.
The System pump will always be enabled as long as the
Heat Demand input is closed and the
SEETINGS:PUMP PRIORITY
is set to
NO.
The
DHW pump will be enabled whenever there is a DHW
call for heat.
A DHW call for heat is when the DHW temperature is
below the (DHW SETPOINT – LOWER BAND) or
when the DHW temperature is below the (DHW
SE UPPER BAND) and boilers are firing.
After a DHW call for heat ends:
A.
The pump will remain on during a post purge
pump cycle until the post purge timer expires.
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Summary of Contents for KN-10
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