Operating information – Lochinvar KNIGHT XL 801 User Manual
Page 63

63
11
Operating information
(continued)
Monitor external limits
Connections are provided on the connection board for 
external limits such as fl ow switch, low water cutoff, 
gas pressure switches, and a louver proving switch. The 
SMART SYSTEM will shut off the burner and inhibit 
relighting whenever any of these external limits open.
Run-time and alarm outputs
The boiler provides dry contacts for indicating when the 
boiler is running, and when it is unable to operate.
Run-time and cycle counting
The control uses two timers to monitor the total hours of 
burner operation. One timer monitors the time the boiler 
is in the Space Heating Mode. The other timer monitors 
the time the boiler is fi ring in the DHW Mode.
The control uses two (2) ignition counters to monitor 
the amount of boiler cycles. The fi rst counter counts all 
ignitions of the control. The second counter counts only 
ignition attempts that have failed. 
Service reminder
The control can be programmed for service reminder 
notifi cation. This notifi cation will become active when 
either a set time frame has expired, or a set amount of 
running hours or cycles has expired (all adjustable by the 
installer). The display will show a Maintenance Required 
screen. The service reminder notifi cation can be reset or 
disabled by the installer.
The time dependent feature has been disabled by the 
manufacturer. To enable this feature change parameter K1 
to the desired time range, reference the Knight XL Service 
Manual for details regarding parameters.
Error logging
The control will hold in memory the last 10 lockouts as 
well as the last 10 blockings. The date and time of the 
occurrence will be recorded as well. Only the 10 most 
current occurrences of each will be held in memory.
Boiler temperature regulation
Operating temperature (target)
The SMART SYSTEM control module senses water 
temperature and regulates boiler fi ring and fi ring rate to 
achieve a target temperature. The target temperature can 
be set between 70°F (21°C) and 190°F (88°C).
• Target temperature is fi xed when the outdoor 
 
sensor is not installed.
• Target temperature is calculated as described 
 
on this page under “Outdoor Reset Operation”
and “Target Temperature Boost” when the
outdoor sensor is connected.
High limit operations
The Knight XL is equipped with adjustable automatic reset and 
manual reset high limits. The automatic reset high limit has a 
maximum set point of 200°F and the manual reset high limit 
has a maximum set point of 210°F.
When the outlet temperature exceeds 200°F, the automatic 
high limit action occurs. The boiler shuts down until the outlet 
water temperature cools below 190°F, and a 60 second timer 
has expired. If the outlet temperature continues to increase, the 
manual reset high limit action will occur at 210°F.
High limit test procedure
1. Turn ON the main power to the boiler by placing the 
 
ON/OFF switch in the ON position.
2. If boiler status reads [SHUTDOWN] place the boiler into 
 
the active position by pressing the RIGHT SELECT [ON]
key.
3. Locate the pinhole (SERVICE button) below the RESET 
 
button on the display board. Insert a thin wire (such as a
paper clip) into the hole and press the button once, hold
for
fi ve (5) seconds to place the boiler into Service Mode.
In Service Mode the boiler will fi re at ignition speed and
will then modulate up to full fi re.
4. From the Status Screen, press the NAVIGATION dial to 
 
access the Set Points Screen.
5. Press the LEFT SELECT [LIMITS] key.
6. Select the manual reset high limit (MRHL) by pressing the 
 NAVIGATION 
dial.
7. Decrease the set point of the MRHL below the outlet 
 temperature by turning the NAVIGATION dial 
 counterclockwise.
8. Press the RIGHT SELECT [SAVE] key.
9. Press the RIGHT SELECT [HOME] key.
10. The new parameters will upload to the control and the 
 
MRHL will function causing boiler shutdown and
[LOCKOUT] to be displayed.
11. Press the RESET button to clear the lockout.
12. Repeat Steps 4, 5 and 6.
13. Set the MRHL to the appropriate set point by turning the 
 
NAVIGATION dial clockwise.
14. Repeat Steps 8 and 9.
Please note that the brackets ([]) denote 
screen status.
NOTICE
Installation & Operation Manual
