Lochinvar Power-fin 502 - Manual (Page 12)

User’s Information Manual
12
3
SMART SYSTEM control module
E: DHW settings
DHW tank set point
When a temperature sensor is installed in the DHW tank, the
DHW tank set point sets the target temperature of the water in
the tank. The user or installer can adjust this set point by
accessing parameter E1.
The temperature range of this
parameter is 60°F (15°C) to 190°F (88°C). The default value is
120°F (49°C).
DHW boiler set point (boiler only)
When a DHW call for heat becomes active, the control will use
the DHW boiler set point to determine the firing rate of the unit
based on the actual outlet water temperature. This parameter
can be changed by the installer by accessing parameter E2. The
temperature range of this parameter is 60°F (15°C) to 200°F
(93°C). The default value is 180°F (82°C).
SH/DHW switching time (boiler only)
The SH/DHW switching time parameter sets the length of time
the control will stay in DHW Mode when a space heating (SH)
call has been received. After this time period has expired the
control will revert to SH Mode. If a DHW call is still active the
timer will reset. After the time period has expired the control
will revert back to DHW Mode. This will continue until one of
the demands has been satisfied. This parameter can be changed
by the installer by accessing parameter E3. The time range of
this parameter is 10 minutes to 240 minutes. The default value
is 30 minutes.
F: Outdoor air reset (boiler only)
Outdoor air shutdown
When the outdoor temperature rises above this point, the
control will block all SH demands (DHW demands will still be
active). This parameter can be changed by the user or the
installer by accessing parameter F5. The temperature range of
this parameter is 0°F (-18°C) to 120°F (49°C). The default value
is 80°F (27°C).
Outdoor air shutdown differential
The outdoor air shutdown differential parameter is the number
of degrees below parameter F5 the outdoor air temperature
must go before the unit will respond to a SH demand. This
parameter can be changed by the user or the installer by
accessing parameter F6.
The temperature range of this
parameter is 0°F (0°C) to 90°F (50°C). The default value is 10°F
(5°C).
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 60 minutes. The default value is 20 minutes.