Lochinvar Power-fin 1701 - Manual (Page 18)

1
Service
18
Service Manual
Boost temperature
If a SH demand lasts longer than the programmed time delay
setting (F9) 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 F8. The
temperature range of this parameter is 0°F (0°C) to 45°F (25°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 F9. The time range for this parameter is
1 minute to 250 minutes. The default value is 20 minutes.
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 40 minutes. The default
value is 1 minute.
Inlet temperature differential for ending anti-cycling
The control will bypass the anti-cycling time if the water
temperature drops too quickly. The control will use the water
temperature the unit 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 unit
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
(5°C).
Ramp delay on/off (M9 boilers only)
When the ramp delay on/off parameter is active, the ramp delay
limits the boiler firing rate when a SH cycle has started. There
are six (6) limiting steps used to limit temperature overshoot
and short cycles, see FIG. 1-2 on page 19 of this manual. This
feature can be turned on or off depending on the installation.
This parameter can be changed by the installer by accessing
parameter G3. The control range of this parameter is 0 = Off,
1 = Ramp Up Only, and 2 = Ramp Up and Ramp Down. The
default value is 0.
Ramp delay settings (M9 boilers only)
When ramp delay is active, there are up to six (6) limiting steps,
as described above in Ramp Delay On/Off. Each step has its own
time period and modulation limit. The installer can adjust these
settings by accessing parameter G4. The settings for each step
are displayed as follows:
G4 Ramp n
mm minutes ppp.p%
Where n is the number of the step, mm is the length of time in
that step, and ppp.p is the maximum modulation allowed
during that step. Upon selecting this parameter, the ramp
number n will be flashing. Use the UP and DOWN keys to
select the step you wish to adjust. Use the NEXT and
PREVIOUS keys to select the setting you wish to adjust. Use the
UP and DOWN keys to adjust the value of each setting. NOTE
THAT THE MODULATION LIMIT IN STEP 6 WILL APPLY
THROUGHOUT THE ENTIRE CALL FOR HEAT. If 100%
modulation is required, the modulation limit in step 6 must be
100%. The default values are 2 minutes at 50% for step 1,
1 minute at 80% for step 2, and 1 minute at 100% for steps 3
through 6.