420010970304 - LP-700 Rev. 000 Rel. 002 Date 4.21.21
62
(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 parameter 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 81 - 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 tem-
perature is reduced 7
o
F every 16 minutes** that the heat call is continu-
ously 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
parameter 2.4.4.
***NOTE: The boiler supply temperature is limited upwards by the fixed maximum temperature (4.2.5) and downwards by the fixed mini-
mum 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 HTP 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 HTP 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 Set-
tings (4.2.6 and 4.2.5), based upon the input temperatures provided by an optional HTP 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)
F. Type of Temperature Control
G. 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 82 - Adjusting the Slope of the Outdoor Reset Curve
