HydroTherm HeatNet KN -6 User Information page 69

DEFAULT SETTINGS & MENU ITEM DESCRIPTIONS
MODE
MIN RUNTIME
MIN OFF TIME
FIRING PRIORITY:
PREDICT START:
BASE LOAD BOILERS:
START
START>MOD
START<OA T
START>RET
STOP
STOP<MOD
STOP>OA T
STOP<RET
DELAY TIME
SENSOR #
TRUE
10 (1-750)
0 (0-10m)
2 1 or 2
YES YES/NO
BASE LOAD BOILER
0 0-1
(START>MOD,
>MOD START<OA T,
START>RET)
100% (20–100)
(40–140)
(60–150F)
(FIRST,
STOP<MOD,
FIRST
START>OA T,
START>RET)
20% (20–100) 20% (20–100)
(40–100 F)
(60–150 F)
0 (0–60 minutes)
Sensors can only be changed when there is no call for heat. The boiler must be in STANDBY.
FIRING MODE
LOFO: Boilers are fired Last On, First Off starting with Lead Boiler
FOFO: Boilers are fired First On, First Off
TRUE: Boilers are fired based on the runtime they report back to
the Master boiler. Boilers with the least runtime are fired first and
boilers with the most runtime are stopped first.
MIXED: Different types of boilers can be mixed in a system and
fired based on (2) Priority sets. Boilers are started and stopped
within their Priority sets based on their runtime hours.
When the firing rotation is based on runtime, this value represents
the interval in hours of runtime before rotation occurs. Boiler to
Boiler.
This is the time in minutes that the boiler must remain OFF before it
can be fired again. Very effective in dynamic systems to minimize
short cycling of a boiler and force the call to the next boiler (with
next shortest runtime if True Runtime is used)
There are (2) Priority settings used by the MIXED boiler rotation
algorithm. Priority 2 is the default and lowest priority. Priority 1
Is the highest priority. A Priority may be assigned to a set of boilers
which fires and rotates based on time and is independent of the other
Priority set.
YES: Predicts the boiler restart point in the heating band while the
temperature of the boiler is drifting down through the band. The
purpose of this is to ensure the temperature remains in the heating
band. It also minimizes temperature swings when the boiler is
stopped and started at low inputs.
This algorithm looks at the size of the band and at what rate the
temperature is falling. It then calculates when to start the boiler
(knowing its starting time) to ensure the boiler starts within the band.
Once the boiler starts, the Add Boiler Delay time starts and
continues to expire in and below the band. This ensures that another
boiler does not start when it leaves the bottom of the band.
This setting works in conjunction with the ADVANCED SETUP:
SYSTEM:OPTION setting BASE LOAD. Currently only (1) base
load boiler is supported using relay K8
Used in Conjunction with DELAY TIME.
The base load relay K8 will close when the Modulation is >%.
The base load relay K8 will close when the OA temp is > T
The base load relay K8 will close when the Return temp is > T.
The base load relay K8 will open when the Modulation is <%.
The base load relay K8 will open when the OA temp is > T.
The base load relay K8 will open when the Return temp is < T.
This setting allows a wait time before firing the base load boiler
once the start condition is met.
SENSORS
The first (4) sensor #'s are reserved as: OUTSIDE AIR, water
HeatNet Control V3 2.x
Page 69