Lochinvar Knight 151 - 211, Service Manual

Page: 23 / 48

1
Service
Service Manual
23
G: Anti-Cycling
Anti-Cycling Time
Once a SH demand has been satisfied, a set amount of time must
elapse before the control will respond to a new SH demand. The
control will block the new heat demand and anti-cycling will be
shown in the display until the time has elapsed or the water
temperature drops below parameter
G2 . This parameter can be
changed by the installer by accessing parameter G1 . The time
range for this parameter is 0 minutes to 10 minutes. The default
value is 1 minute.
Anti-Cycling Override Differential
The control will bypass the anti-cycling time if the water
temperature drops too quickly. The control will use the water
temperature the boiler was at when it shut off as the starting
point. If the temperature drops below the temperature
parameter the control will abort anti-cycling and allow the
boiler to fire. This parameter can be changed by the installer by
accessing parameter
G2 . The temperature range of this
parameter is 0°F (0°C) to 54°F (30°C). The default value is 10°F
(6°C).
Ramp Delay (Enable / Disable)
This parameter allows the installer to enable or disable the SH
ramp delay by accessing parameter
G4 .
Outdoor Air Shutdown Differential (SH1 - SH3)
The outdoor air shutdown differential parameter is the
number of degrees below parameters
F5 , F10 and F15 the
outdoor air temperature must go before the boiler will
respond to a SH demand. These parameters can be
changed by the installer by accessing parameters
F6 , F11
and F16 . The temperature range of this parameter is 0°F
(0°C) to 90°F (50°C). The default value is 10°F (6°C).
Shift Reset Curve (SH1 - SH3)
There is a shift reset curve for each outdoor reset. The shift
reset curve parameter shifts the actual set point above the
calculated set point the number of degrees in this
parameter. These parameters can be changed by the
installer by accessing parameter
F7 , F12 and F17 . The
temperature range of this parameter is -17°F (-27°C) to
18°F (-8°C). The default value is 0°F (0°C). This feature
will be active if this parameter is set to anything other than
0°F (0°C).
Boost Temperature
If a SH demand lasts longer than the programmed time
delay setting (
F19 ) and there have been no DHW demands,
the control will increase the water temperature set point by
the amount in this parameter. If the SH demand continues
through another time period, the set point will be increased
again. This will continue until either the SH demand ends,
a maximum of 20 increases has occurred, or the maximum
set point has been reached. Once the SH demand has been
satisfied the set point will revert back to its calculated
setting. The boost temperature can be changed by the
installer by accessing parameter
F18 . The temperature
range of this parameter is 0°F (0°C) to 25°F (-4°C). The
default value is 0°F (0°C). This feature will be active if this
parameter is set to anything other than 0°F (0°C).
Boost Time
The boost time parameter sets the amount of time that
must elapse with a SH demand before the water
temperature set point will be increased. This parameter
can be changed by the installer by accessing parameter
F19 .
The time range for this parameter is 0 minute to 50
minutes. The default value is 0 minutes.