Lochinvar 400 - 801 Boiler User Manual


 
Service Manual
19
1 Service (continued)
Viewable and changeable control parameters
A: General
Date and Time
The control uses an internal clock for the night setback
feature and for logging of events. For these features to work
correctly, the clock must be set when the boiler is first
installed or anytime the boiler has been powered off for more
than four (4) hours. To set the clock, parameter A1 must be
accessed.
Software Version
The software version allows the user to view the software
version in use by the control. This software controls the
operation of the boiler. When a new software version
becomes available, the existing control can be replaced with a
new control to update the software.
Software version is read only.
Temperature units (°C / °F)
The control can be configured to display temperature in
either °C or °F. This parameter can be changed by the user or
the installer by accessing parameter A3. The default is °F.
Space Heating (SH) and Domestic Hot Water (DHW)
Night Setback Offset
The unit’s internal clock can be set up to run at a lower set
point temperature during unoccupied times. Both the space
heating and DHW can be programmed for night setback.
When in night setback, the control reduces the set point by a
fixed amount. For space heating, it subtracts the space
heating night setback offset from each of the SH user set
points (parameters B1, B6, and B9), or the calculated outdoor
reset set point (if lower). For DHW, it subtracts the DHW
night setback offset from the tank set point (parameter E2).
NOTE: The DHW night setback will not work without a tank
sensor installed.
The installer may adjust the space heating night setback offset
by accessing A4 and the DHW night setback offset by
accessing parameter A7. The minimum setting is 0°F (0°C)
and the maximum setting is 90°F (50°C).
Space Heating (SH) and Domestic Hot Water (DHW)
Night Setback On Times
This is the time in which the SH Night Setback Offset becomes
active. There are 7 start times and 7 stop times each for the
space heating and DHW night setback features. Both may be set
to any time within a 7-day week. These settings are referred to
as triggers. Multiple start or stop triggers may be set within a
single day, if desired. When a start trigger and a stop trigger are
set to the same time, the stop trigger has priority. The installer
may adjust the space heating night setback start triggers by
accessing parameter A5. The DHW start triggers in parameter
A8. This screen shows the start trigger number, the day of the
week, and the time of day.
1. When the screen is first accessed, start trigger number 1
is shown. If a different trigger number is desired, the
installer can rotate the NAVIGATION dial until the desired
trigger number is displayed. Once the desired trigger
number is selected, the installer can press the SCROLL
knob and the day of the week will start to flash.
2. The installer can adjust the day of the week to the one he
wishes to set. Once the day is set, the installer can press the
NAVIGATION dial and the hour will begin to flash.
3. After setting the hour, the installer can press the SCROLL
knob and the minutes will flash. Once all settings have been
made, the installer can press the RIGHT SELECT [SAVE]
key. The installer can now select a different trigger and
adjust the settings for that trigger.
4. Once all adjustments are made, the installer can press the
RIGHT SELECT [SAVE] key to save all of the new settings
and return to the A menu, or press the LEFT SELECT
[EXIT] key to return to the A menu without saving the
changes.
Space Heating (SH) and Domestic Hot Water (DHW)
Night Setback Off Times
The corresponding space heating night setback stop triggers are
set by accessing parameter A6. The stop triggers for the DHW
night setback feature can be adjusted by accessing parameter A9.
The adjustment procedure for these parameters is identical to
the space heating start triggers described above.
CAUTION
Before changing parameters, note the
settings so that the unit can be returned to
its original operating parameters.
NOTICE
The internal clock does not adjust for
Daylight Savings Time and therefore,
will require a manual adjustment.
Please note that the brackets ([]) denote
screen status.
NOTICE