62
Part 1 - General Safety Information
(e.g. Parameter 4.2.1 for Zone 1)
0 = Fixed Outlet Temperature -
When operating for central heating, the boiler operates at a fixed supply temperature equal to the setting of pa-
rameter 4.0.2, which is adjustable via the CH + and - buttons on the home screen, with a range defined by parameters 4.2.5 and 4.2.6. The supply
temperature is fixed and does not change due to indoor or outdoor temperature conditions.
Figure 67 - Basic Temp. Control Example (4.2.0 = 1)
1 = Basic Temp. Control
- The boiler uses the ON/OFF condition of the room
thermostat to boost/reduce the boiler target temperature. With a starting*
(first time) boiler target temperature of 136
o
F (4.2.0 = 1) or 95
o
F (4.2.0 = 0), the
function boosts the target temperature by 7
o
F every 16 minutes** a call for
heat is continuously active. Similarly, the target temperature is reduced 7
o
F
every 16 minutes** that the heat call is continuously inactive. The temperature
will boost/reduce a maximum of 3 times (21
o
F)*** for a given thermostat ON/
OFF cycle.
*NOTE:
The boiler starting target temperature can be manually offset up or
down via the Parallel Shift setting (4.2.3), which is adjustable from the home
screen via the CH + and - buttons.
**NOTE:
The default boost interval of 16 minutes can be adjusted via parame-
ter 2.4.4.
***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).
2 = Indoor Temp. Reset -
The boiler target temperature automatically adjusts between the Min and Max Temperature Settings (4.2.6 and 4.2.5),
based on the input temperature provided by an optional NTI Room Sensor, in accordance with the following formula:
Boiler Target Temp = Min Temp (4.2.6) + Room Sensor Influence (4.2.4) X [Room Setpoint - Room Temp] + Parallel Shift of Reset Curve (4.2.3)
3 = Outdoor Temp. Reset -
The boiler target temperature automatically adjusts between the Min and Max Temperature Settings (4.2.6 and
4.2.5), based on the input temperature provided by the included Outdoor Sensor (or Internet Weather via WiFi connection), in accordance with
the following formula:
Boiler Target Temp = Min Temp (4.2.6) + Slope of Outdoor Reset Curve (4.2.2) X [Room Setpoint (4.0.0) - Outdoor Temp] + Parallel Shift of Reset Curve (4.2.3)
Where: Room Setpoint, in the absence of an NTI Room Sensor, defaults to 66
o
F and is adjustable via parameter 4.0.0.
4 = Indoor and Outdoor Temp. Reset -
The boiler target temperature automatically adjusts between the Min and Max Temperature Settings
(4.2.6 and 4.2.5), based upon the input temperatures provided by an optional NTI Room Sensor AND the included Outdoor Sensor (or Internet
Weather via WiFi connection), in accordance with the following formula:
Boiler Target Temp = Min Temp (4.2.6) + Slope of Outdoor Reset Curve (4.2.2) X {Room Sensor Influence (4.2.4) X [Room Setpoint - Room Temp] + [Room Setpoint -
Outdoor Temp]} + Parallel Shift of Reset Curve (4.2.3)
J. Slope of Outdoor Reset Curve
(e.g. Parameter 4.2.2 for Zone 1)
The boiler control adjusts the supply temperature according
to the outdoor temperature. The lower the outdoor
temperature, the higher the boiler supply temperature, and
vice versa.
The supply temperature needed to efficiently satisfy a call for
heat from a thermostat depends on the heating system and
building conditions (building materials, insulation, etc.)
The Slope of the Outdoor Reset Curve may be adjusted
to adapt the boiler supply temperature to installation
conditions.
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).
179 °F
120 °F
20 °F
0,4
3,5
1,3
Default
65 °F
80 °F
Tar
get CH supply t
emper
atur
e
Tar
get CH supply t
emper
atur
e
Tar
get CH supply t
emper
atur
e
Outdoor temperature
179 °F
120 °F
Outdoor temperature
Decrease parallel shift
Increase parallel shift
+25°F
0 °F
-25°F
Default
179 °F
120 °F
Outdoor temperature
Figure 68 - Adjusting the Slope of the Outdoor Reset Curve
I. Type of Temperature Control
Part 9 - Controls
Содержание FTVN
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