Dhw Method 4: Space Heating With Dhw Override Of Setpoint On Master; Dhw Method 5: Dhw Of A Local Boiler; S Tank - HydroTherm HeatNet KN -6 User Information

OPTIONAL FEATURES
the tank setpoint is set to 140F and the heat band
is set to 10F, then the tank temperature will rise
to 145F before the first boiler turns off (setpoint
=140F +/- heat band/2). With (2) boilers
running, the SHED BOILER DELAY time
could add to the tank temperature. So, to ensure
that all boilers are shut off at the upper point of
the heat band, set the SHED BOILER DELAY
time to 0 or other small value. This will
effectively turn off all boilers at the upper heat
band point of: (example) 145F.
Now, there is one more thing to consider, the
pump's post purge time. Dumping the heat from
all boilers (that were running) using a pump post
purge cycle will have an effect on the tank's
water temperature. Consider this when
establishing the local pump's POST PURGE
TIME.
3. Connect the Local Pump relay contact on J13 to
enable the DHW pump. Set its post purge time to
dump the boiler's heat into the tank when the
boiler shuts off. Be aware that this may heat the
tank above the setpoint‟s upper heat band
temperature.
4. Enable the system by placing the
LOCAL/REMOTE switch on the Master to the
LOCAL position.
DHW METHOD 4: Space Heating
with DHW Override of Setpoint on
Master
This method is for controlling DHW utilizing a tank
thermostat connected to a Master boiler. This method
requires a thermostat input to the OR OVR. When the
thermostat contact closes across the input OR OVR (J12A
.7 & .8), the control will sense this closure and override the
space heating setpoint with the DHW setpoint.
ADVANCED SETUP: DISTRIBUTED CTRL:
MASTER TYPE: AUTO.
This method is for backwards compatibility.
In this mode, the boiler will fire to the DHW setpoint.
The settings for space heating will be used except for
the addition of controlling the DHW pump/valve.
13. Wire the dry contact from the thermostat on the
tank to the input on J12A terminal 7 & 8. Also, at
this time wire any pump or valve from the DHW
Pump relay (normally open) contact (J13
terminals 9, 10) to control flow of the heating
water into the tank's coil.
14. Enter the DOMESTIC HOT WATER MENU.
When prompted for DHW BOILER?, enter NO.
15. DHW SETPOINT The setpoint should reflect the
temperature desired in the heating loop when a tank is
calling for DHW heat.
16. LOWER DHW DIFF This is not used.
17. UPPER DHW DIFF This is not used.
18. DHW PRIORITY Setting this value to YES will turn
OFF the system pump when the DHW setpoint override
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 THE. 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
HeatNet Control V3 2.x
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