Parallel Shift Of Reset Curve; Auto Boost - NTI FTVN085 Installation Start-Up Maintenance

K. Parallel Shift of Reset Curve
(e.g. Parameter 4.2.3 for Zone 1)
When the Reset Curve results in a boiler target temperature
that is too high or too low (i.e., heats the building too quickly
or slowly), Parallel Shift can be used to offset the curve up or
down to increase or decrease the boiler target temperature.
NOTE: Adjusting Parallel Shift is only possible when Auto
Boost is OFF (4.7.5 = 0).
The Parallel Shift can be adjusted from the home screen using the CH + and - buttons (Figure
60, Item 8).
With the first press of the CH + or - button, the display shows the current CH target temperature
o
(e.g., 130 F).
After a 3-5 second delay, the display begins flashing the current offset (Parallel Shift) setting.
Subsequent CH + or - button presses adjusts the offset up or down.
After a few seconds the display shows the new CH target temperature (e.g., 138
to the home screen.
L. Auto Boost
(e.g. Parameter 4.7.5 for Zone 1)
When enabled (4.7.5 = 1), Auto Boost acts to automatically
adjust the Slope of the Outdoor Reset Curve to better
match the needs of the heating system. The function boosts
the boiler target temperature by increasing the Slope 10%
every 10 minutes a call for heat is continuously active, to
a maximum of 2X the nominal Slope setting (4.2.2). While
the heat call is satisfied, the Slope decreases by 1% every
minute to a minimum of the nominal Slope setting (4.2.2).
Auto Boost is only applicable when 4.2.1 = 3 or 4.
NOTE: The boiler supply temperature is limited upwards by
the fixed maximum temperature (4.2.5) and downwards by
the fixed minimum temperature (4.2.6).
Outdoor temperature
Part 1 - General Safety Information
179 °F
Decrease parallel shift
120 °F
Outdoor temperature
Figure 70 - Parallel Shift of Reset Curve
o
F), then returns
Thermostat
On
Thermostat
O
+ 10%
10 min 10 min
Figure 69 - Automatic Boost
Part 9 - Controls
Increase parallel shift
AUTO
Thermostat
O
+ 10%
Each line represents a
1% decrease in setpoint
per minute
after the call has been met
10 min
+25°F
0 °F Default
-25°F
1
63