Lochinvar KNIGHT 400 - 801 User manual

Service Manual
Models: 400 - 801
This manual must only be used by a
qualified heating installer / service
technician. Read all instructions,
including this manual and the
Knight XL Installation and
Operation Manual, before
installing. Perform steps in the
order given. Failure to comply
could result in severe personal
injury, death, or substantial
property damage.
WARNING
Save this manual for future reference.
KBXII-SER Rev B

2
Hazard definitions
The following defined terms are used throughout this manual to bring attention to the presence of hazards of various risk levels or
to important information concerning the life of the product.
DANGER
WARNING
CAUTION
CAUTION
NOTICE
DANGER indicates an imminently hazardous situation which, if not avoided, will result in death or serious
injury.
WARNING indicates a potentially hazardous situation which, if not avoided, could result in death or serious
injury.
CAUTION indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate
injury.
CAUTION used without the safety alert symbol indicates a potentially hazardous situation which, if not
avoided, may result in property damage.
NOTICE indicates special instructions on installation, operation, or maintenance that are important but not
related to personal injury or property damage.
CONTENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Hazard Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
PLEASE READ BEFORE PROCEEDING . . . . . . . . . . . . 3
Handling Ceramic Fiber Materials . . . . . . . . . . . . . . . . . . . 3
When servicing boiler . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Boiler operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Boiler water . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Freeze protection fluids . . . . . . . . . . . . . . . . . . . . . . . . 4
WHAT IS IN THIS MANUAL . . . . . . . . . . . . . . . . . . . . . . . 5
1. SERVICE
Near Boiler Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
The Knight XL Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Control Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Control Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
General Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Sequence of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . 11-12
Display Panel Menu Access . . . . . . . . . . . . . . . . . . . . . . 13
Display Panel Parameter Access . . . . . . . . . . . . . . . . . . 14
Parameter Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-18
Viewable and Changeable Control Parameters . . . . . . . 19-27
2. MAINTENANCE
Maintenance and Annual Startup . . . . . . . . . . . . . . . . . . 28-32
3. TROUBLESHOOTING
Before Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Check Control Module Fuses . . . . . . . . . . . . . . . . . . . . . 33
Table 3-1 - Troubleshooting Chart - No Display . . . . . . . 34
Checking Temperature Sensors . . . . . . . . . . . . . . . . . . . 35
Table 3-3 - Troubleshooting Chart - Noisy System . . . . . 36
Table 3-4 - Troubleshooting Chart - Fault Messages . . . 37-43
Combustion Analysis Procedure . . . . . . . . . . . . . . . . . . . 44
Table 3-5 - Troubleshooting Chart - Combustion Levels 44
Table 3-6 - Flue Products . . . . . . . . . . . . . . . . . . . . . . . . 44
Gas Valve Adjustment Procedure . . . . . . . . . . . . . . . . . . 45
Revision Notes . . . . . . . . . . . . . . . . . . . . . . . . . Back Cover
Contents

Service Manual
Please read before proceeding
Installer – Read all instructions,
including this manual and the Knight XL
Installation and Operation Manual,
before installing. Perform steps in the
order given.
User – This manual is for use only by a
qualified heating installer/service
technician. Refer to the Knight XL User’s
Information Manual for your reference.
Have this boiler serviced/inspected by a
qualified service technician at least
annually.
Failure to comply with the above could
result in severe personal injury, death or
substantial property damage.
When calling or writing about the boiler –
Please have the boiler model and serial
number from the boiler rating plate.
Consider piping and installation when
determining boiler location (see the Knight
XL Installation and Operation Manual).
Any claims for damage or shortage in
shipment must be filed immediately against
the transportation company by the
consignee.
3
Handling ceramic fiber materials
REMOVAL OF COMBUSTION CHAMBER LINING
The combustion chamber insulation in this appliance contains ceramic fiber material. Ceramic fibers can
be converted to cristobalite in very high temperature applications. The International Agency for Research
on Cancer (IARC) has concluded, “Crystalline silica inhaled in the form of quartz or cristobalite from
occupational sources is carcinogenic to humans (Group 1).” Normal operating temperatures in this
appliance are below the level to convert ceramic fibers to cristobalite. Abnormal operating conditions would
have to be created to convert the ceramic fibers in this appliance to cristobalite.
The ceramic fiber material used in this appliance is an irritant; when handling or replacing the ceramic
materials it is advisable that the installer follow these safety guidelines.
Avoid breathing dust and contact with skin and eyes.
• Use NIOSH certified dust respirator (N95). This type of respirator is based on the OSHA
requirements for cristobalite at the time this document was written. Other types of respirators may
be needed depending on the job site conditions. Current NIOSH recommendations can be found on
the NIOSH website at http://www.cdc.gov/niosh/homepage.html. NIOSH approved respirators,
manufacturers, and phone numbers are also listed on this website.
• Wear long-sleeved, loose fitting clothing, gloves, and eye protection.
Apply enough water to the combustion chamber lining to prevent airborne dust.
Remove the combustion chamber lining from the appliance and place it in a plastic bag for disposal.
Wash potentially contaminated clothes separately from other clothing. Rinse clothes washer
thoroughly.
NIOSH stated First Aid.
Eye: Irrigate immediately.
Breathing: Fresh air.
WARNING NOTICE
WARNING

4
Service Manual
Please read before proceeding
When servicing boiler –
• To avoid electric shock, disconnect electrical supply
before performing maintenance.
• To avoid severe burns, allow boiler to cool before
performing maintenance.
Boiler operation –
• Do not block flow of combustion or ventilation air to
the boiler.
• Should overheating occur or gas supply fail to shut off,
do not turn off or disconnect electrical supply to
circulator. Instead, shut off the gas supply at a location
external to the appliance.
• Do not use this boiler if any part has been under water.
The possible damage to a flooded appliance can be
extensive and present numerous safety hazards. Any
appliance that has been under water must be replaced.
Boiler water –
• Thoroughly flush the system (without boiler
connected) to remove sediment. The high-efficiency
heat exchanger can be damaged by build-up or
corrosion due to sediment.
• Do not use petroleum-based cleaning or sealing
compounds in the boiler system. Gaskets and seals in
the system may be damaged. This can result in
substantial property damage.
• Do not use “homemade cures” or “boiler patent
medicines”. Serious damage to the boiler, personnel,
and/or property may result.
• Continual fresh make-up water will reduce boiler life.
Mineral buildup in the heat exchanger reduces heat
transfer, overheats the stainless steel heat exchanger, and
causes failure. Addition of oxygen carried in by makeup
water can cause internal corrosion. Leaks in boiler
piping must be repaired at once to prevent the
introduction of makeup water.
Freeze protection fluids –
• NEVER use automotive antifreeze. Use only inhibited
propylene glycol solutions which are specifically
formulated for hydronic systems. Ethylene glycol is
toxic and can attack gaskets and seals used in hydronic
systems.

Service Manual
5
What is in this manual?
Service
Near boiler piping
• Typical system components
The Knight XL display
• Display panel readout, buttons and their functions
Control module inputs
• Control module inputs and options
Control module outputs
• Control module outputs and options
General
• How the boiler operates
• How the control module operates
• Access modes -- user and installer
• Sequence of operation -- Domestic Hot Water
(DHW)/space heating
Control panel menu access
• Accessing programming mode and locating menus
(See separate guide covering the interface.)
Control panel parameter access
• Accessing and changing parameters from the display panel
Quick start information -- parameter
table
• An index of available adjustments and readouts, where to
access them and where to find detailed information.
Knight XL operation
• A: General
• B: Temperature Setting
• C: Data Logging
• D: Functions
• E: DHW Settings
• F: Outdoor Reset
• G: Anti-cycling
• H: Control Modes
• I: Circulation Pumps
• J: Building Management System (BMS)
• K: Service Notification
Maintenance
• Service and maintenance schedules
• Address reported problems
• Inspect boiler area and boiler interior
• Clean condensate trap
• Check all piping for leaks
• Check air openings
• Flue vent system and air piping
• Check water system
• Check expansion tank
• Check boiler relief valve
• Inspect ignition electrode
• Check ignition ground wiring
• Check all boiler wiring
• Check control settings
• Perform start-up and checks
• Check burner flame
• Check flame signal
• Check flue gas temperature
• General maintenance
• Review with owner
• Cleaning boiler heat exchanger
• Oiled bearing circulators
Troubleshooting
• Troubleshooting table - No display
• Checking temperature sensors
• Sensor tables
• Troubleshooting table - Fault messages displayed on
boiler interface
• Combustion analysis procedure
• Gas valve adjustment procedure

1 Service
6
Service Manual
Y-STRAINER
(RECOMMENDED)
BOILER PUMP
INDIRECT
DOMESTIC
HOT WATER
TANK
SYSTEM PUMP
TO FLOOR
DRAIN
TO
FROM
FROM
SYSTEM
TO
SYSTEM
DOMESTIC HOT
WATER PUMP
SYSTEM SENSOR
DIRT SEPARATOR
Near boiler piping
This piping reference is included to specify the Near Boiler Piping specific to the Knight XL. This piping scheme is important
for proper operation of the SMART SYSTEM control. See the Knight XL Installation and Operation Manual for more detailed
piping diagrams.

Service Manual
7
1 Service (continued)
NAVIGATION DIAL
The Knight XL display
The information on the bottom of the display shows the functions of the two SELECT keys (on either corner), and the
NAVIGATION dial (in the center):
MENU = Left SELECT Key
SETPOINTS = NAVIGATION Dial - Pressing Down
SHDN = Right SELECT Key

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Service Manual
1 Service
GAS PRESSURE SWITCH
DHW THERMOSTAT
ROOM THERMOSTAT /
ZONE CONTROL
FLOW SWITCH
SYSTEM SENSOR
OUTDOOR SENSOR
BUILDING MANAGEMENT
SYSTEM
LOW VOLTAGE
CONNECTION
BOARD
INLET TEMPERATURE
SENSOR
OUTLET TEMPERATURE /
HI-LIMIT SENSOR
FLUE GAS SENSOR
LOUVER PROVING SWITCH
FLAME SENSOR
LOW WATER CUTOFF
BLOCKED DRAIN SWITCH
DISPLAY PANEL
PC INTERFACE
SMART CONTROL
MODULE
AIR PRESSURE SWITCH
SYSTEM PUMP SPEED CONTROL
Control inputs

1 Service
Service Manual
9
1 Service (continued)
LOW VOLTAGE
CONNECTION
BOARD
SMART CONTROL
MODULE
ALARM BELL
LOUVER RELAY
RUN TIME CONTACTS
BUILDING MANAGEMENT
SYSTEM
BOILER PUMP
SYSTEM PUMP
DHW PUMP
IGNITOR
BLOWER
GAS VALVE
DISPLAY PANEL
PC INTERFACE
Control outputs

1 Service
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Service Manual
1 Service
General Operation
How the boiler operates
The Knight XL uses an advanced stainless steel heat
exchanger and an electronic control module that allows
fully condensing operation. The blower pulls in gas and air
and pushes flue products out of the boiler through the heat
exchanger and flue piping. The control module regulates
blower speed to control boiler firing rate. The gas valve
senses the amount of air flowing into the boiler and allows
only the right amount of gas to flow.
How the control module operates
The Knight XL control module receives input from boiler
sensors. The control module activates and controls the
blower and gas valve to regulate heat input and switches
boiler, DHW and system pumps on and off as needed. The
user/installer programs the module to meet system needs
by adjusting control parameters. These parameters set
operating temperatures and boiler operating modes. Boiler
operation can be based on boiler outlet water temperature,
boiler return water temperature or system supply
temperature, depending on the parameter setting.
Sequence of operation
Table 1-1 shows control module normal sequences of
operation for space heating and DHW operation. The
combined operation sequence is for a typical application,
programmed to provide DHW priority.
Access modes
User
The user can adjust space heating and tank target
temperatures by pressing the NAVIGATION dial when
“SETPOINTS” is flashing at the bottom of the display. The
date and time, and the temperature units can also be changed.
Installer
Most parameters are available only to the installer, accessible
by entering the installer password (5309).
Saving parameters (reference the Parameter Table -
Table 1-4 on pages 15 - 18 of this manual)
Please note that the brackets ([]) denote
screen status.
NOTICE
To save parameters and exit programming:
Press the RIGHT SELECT [SAVE] key and then press the
RIGHT SELECT [HOME] key.
To enter a parameter and continue programming:
Press the RIGHT SELECT [SAVE] key 1 time to return to the
parameter listings; press again to return to the menu listings.
Remember to press the RIGHT SELECT [HOME] key when
finished programming in order to save the changes made.

1 Service
Service Manual
1 Service (continued)
Table 1-1 Sequence of Operation
OPERATION DISPLAY
1. Upon a call for heat, the gas pressure switch(es) must be closed.
2. Once the gas pressure switch(es) are closed, the control turns
on the appropriate pumps (system and boiler pumps for space
heating, DHW pump for DHW).
The flow switch and/or LWCO must close.
3. The control turns on power to the louver relay.
The louver proving switch, air pressure switch, and blocked
drain switch must close.
4. The control starts a 15 second prepurge cycle by initiating the
blower.
5. The control starts a 4 second trial for ignition by firing the spark
electrode and opening the gas valve.
6. If flame is not detected within 1 second after the sparking ends,
the control will perform a 10 second post-purge, then start
another prepurge cycle and try to light the burner again. On the
501 and larger models, the control will lock out if this second
attempt also fails. On the 400 model, the control will perform a
total of 4 attempts before locking out.
7. If flame is detected, it holds the firing rate steady for 5 seconds
to let the flame stabilize, then it begins to modulate the firing rate
based on a set point or some other command (such as a 0-10V
BMS signal).
11

1 Service
12
Service Manual
1 Service
Table 1-1 (continued from previous page) Sequence of Operation
OPERATION DISPLAY
8. If the space heating call for heat is active, and the tank
thermostat or sensor starts a DHW call for heat, the boiler will
switch to the DHW mode. If programmed for normal DHW
operation (not as a zone), the DHW pump will turn on first, then
the boiler pump will turn off 2 seconds later.
This will divert the boiler’s outlet water from the heating system
and send it to the tank coil instead.
The control will then modulate to maintain the outlet
temperature to the DHW boiler set point.
9. If the boiler is not part of a Cascade, and both the space heating
and DHW calls for heat remain active long enough, the boiler will
switch back and forth between the two heating modes until one
of them is satisfied.
10. Once both calls for heat are satisfied, the control will turn off the
burner. The blower will continue to run during a 10 second
postpurge.
11. Any pumps that are running will continue to run for their
respective pump delay times before turning off, unless
programmed to remain on continuously.
A 60 second anti-cycle period will start, which will delay any
new call for heat until it times out.
12. In Standby, ready to start a new cycle.

1 Service
Service Manual
13
1 Service (continued)
Display panel menu access
Table 1-2 Use this procedure to access menus from the display panel
BUTTON SCREEN
STATUS OPERATION DISPLAY
[SHDN] Press the RIGHT SELECT soft key [SHDN].
[YES] Press the LEFT SELECT soft key [YES].
[MENU] Press and hold the LEFT SELECT soft key [MENU]
for five (5) seconds.
Rotate the NAVIGATION dial clockwise until 5 is
displayed (first digit on the left).
Press the NAVIGATION dial to select the next digit.
Rotate the NAVIGATION dial clockwise until 3 is
shown in the display.
Press the NAVIGATION dial 2 times to move to the
last digit. Rotate the NAVIGATION dial
counterclockwise until 9 is displayed.
[SAVE] Press the RIGHT SELECT soft key [SAVE].
Rotate the NAVIGATION dial counterclockwise to
select a category.

1 Service
14
Service Manual
1 Service
Display panel parameter access
Table 1-3 This is a typical example of accessing a parameter, shown for parameter Temperature Settings, MIN
SH Setpt
BUTTON SCREEN
STATUS OPERATION DISPLAY
This example shows how to access parameter Temperature Settings. The first display shown is at the beginning
of the menu listings, after entering the installer access code.
Rotate the NAVIGATION dial counterclockwise until
the arrow (>) is next to TEMPERATURE SETTINGS.
Press the NAVIGATION dial one time.
Rotate the NAVIGATION dial counterclockwise until
the arrow (>) is next to MIN SETPT.
Press the NAVIGATION dial one time.
Rotate the NAVIGATION dial to the desired
temperature.
[SAVE] Press the RIGHT SELECT soft key [SAVE] one time.
[EXIT] Press the LEFT SELECT soft key [EXIT] if all desired
changes have been made.
[HOME] Press the LEFT SELECT soft key [HOME].

1 Service
Service Manual
15
1 Service (continued)
Parameter table
Table 1-4 This table lists SMART SYSTEM control module parameters and where to access them
Menu Sub
Item Description See Page
User Access Installer Access
Display Modify Display Modify
A
1Date and Time 19 Yes Yes Yes Yes
2Software Version (read only) 19 No No Yes No
3Temperature Units (ºC/ºF) 19 Yes Yes Yes Yes
4SH Night Setback Offset 19 No No Yes Yes
5SH Night Setback On Times 19 No No Yes Yes
6SH Night Setback Off Times 19 No No Yes Yes
7DHW Night Setback Offset 19 No No Yes Yes
8DHW Night Setback On Times 19 No No Yes Yes
9DHW Night Setback Off Times 19 No No Yes Yes
10 Display Timeout 20 No No Yes Yes
B
1SH1 Set Point 20 Yes Yes No No
2Minimum SH Set Point 20 No No Yes Yes
3Maximum SH Set Point 20 No No Yes Yes
4SH1 Offset Set Point 20 No No Yes Yes
5SH1 Differential Set Point 20 No No Yes Yes
6SH2 Set Point 20 Yes Yes No No
7SH2 Offset Set Point 20 No No Yes Yes
8SH2 Differential Set Point 20 No No Yes Yes
9SH3 Set Point 20 Yes Yes No No
10 SH3 Offset Set Point 20 No No Yes Yes
11 SH3 Differential Set Point 20 No No Yes Yes
12 3-Way Valve Time 20 No No Yes Yes
C1Reset Last 10 Errors 20 No No Yes Yes
D
1Service Mode Delay 20 No No Yes Yes
2Freeze Protection Pump On 20 No No Yes Yes
3Freeze Protection Burner On 20 No No Yes Yes
4Freeze Protection Burner Differential 20 No No Yes Yes
GENERAL
TEMPERATURE SETTINGS
DATA
LOGGING
FUNCTIONS

1 Service
16
Service Manual
1 Service
Parameter table
Table 1-4 (continued from previous page) This table lists SMART SYSTEM control module parameters and where
to access them
Menu Sub
Item Description See Page
User Access Installer Access
Display Modify Display Modify
E
1DHW Boiler Set Point 21 No No Yes Yes
2DHW Tank Set Point 21 Yes Yes Yes Yes
3Tank Set Point Differential 21 No No Yes Yes
4Boiler Set Point Offset 21 No No Yes Yes
5Boiler Set Point Differential 21 No No Yes Yes
6SH/DHW Switching Time 21 No No Yes Yes
7DHW/SH Switching Time 21 No No Yes Yes
8Tank Minimum Set Point 21 No No Yes Yes
9Tank Maximum Set Point 21 No No Yes Yes
10 DHW Type (Normal, Zone) 21 No No Yes Yes
11 Fan Speed Limiting for Indirect DHW Tank 21 No No Yes Yes
F
1Low Outdoor Temperature 22 No No Yes Yes
2High Outdoor Temperature 22 No No Yes Yes
3SH1 Set Point at Low Outdoor Temp 22 No No Yes Yes
4SH1 Set Point at High Outdoor Temp 22 No No Yes Yes
5Outdoor Air Shutdown SH1 22 No No Yes Yes
6Outdoor Air Shutdown Differential SH1 23 No No Yes Yes
7Shift Reset Curve SH1 23 No No Yes Yes
8SH2 Set Point at Low Outdoor Temp 22 No No Yes Yes
9SH2 Set Point at High Outdoor Temp 22 No No Yes Yes
10 Outdoor Air Shutdown SH2 22 No No Yes Yes
11 Outdoor Air Shutdown Differential SH2 23 No No Yes Yes
12 Shift Reset Curve SH2 23 No No Yes Yes
13 SH3 Set Point at Low Outdoor Temp 22 No No Yes Yes
14 SH3 Set Point at High Outdoor Temp 22 No No Yes Yes
15 Outdoor Air Shutdown SH3 22 No No Yes Yes
16 Outdoor Air Shutdown Differential SH3 23 No No Yes Yes
17 Shift Reset Curve SH3 23 No No Yes Yes
DHW SETTINGS
OUTDOOR RESET

1 Service (continued)
Service Manual
17
Menu Sub
Item Description See Page
User Access Installer Access
Display Modify Display Modify
F
18 Boost Temperature 23 No No Yes Yes
19 Boost Time 23 No No Yes Yes
G
1Anti-Cycling Time 23 No No Yes Yes
2Anti-Cycling Override Differential 23 No No Yes Yes
3Ramp Delay (Enable, Disable) 23 No No Yes Yes
4SH Ramp Delay 24 No No Yes Yes
H
1Controlling Sensor 24 No No Yes Yes
2BMS Tstat Input (Active/Inactive) 24 No No Yes Yes
3BMS (Active/Inactive) 24 No No Yes Yes
4ModBus (Active/Inactive) 25 No No Yes Yes
5ModBus T/O (Timeout) 25 No No Yes Yes
6Cascade Address 25 No No Yes Yes
7Cascade Type (L/L / EFF) 25 No No Yes Yes
8Max Cascade Outlet Set Point 25 No No Yes Yes
9Cascade Offset 25 No No Yes Yes
10 Cascade Off/On Differential 25 No No Yes Yes
11 Min On/Off Time 25 No No Yes Yes
12 Min Next On Time 25 No No Yes Yes
13 Boiler Size 25 No No Yes Yes
I
1System Pump Delay 26 No No Yes Yes
2Boiler Pump Delay 26 No No Yes Yes
3DHW Pump Delay 26 No No Yes Yes
4Boiler Pump Anti-Seize Delay 26 No No Yes Yes
5Boiler Pump Min Voltage 26 No No Yes Yes
6System Pump Type (CFH/WWSD) 26 No No Yes Yes
7DHW Pump Anti-Seize Delay 26 No No Yes Yes
8System Pump Anti-Seize Delay 26 No No Yes Yes
Parameter table
Table 1-4 (continued from previous page) This table lists SMART SYSTEM control module parameters and where
to access them
CONTROL MODES
OUTDOOR
RESET
ANTI-CYCLING
CIRCULATION PUMPS

1 Service
Service Manual
18
Menu Sub
Item Description See Page
User Access Installer Access
Display Modify Display Modify
J
1BMS Type (Power / Set Point) 26 No No Yes Yes
2Volts at Min 26 No No Yes Yes
3Volts at Max 26 No No Yes Yes
4Rate at Min Volts 26 No No Yes Yes
5Rate at Max Volts 26 No No Yes Yes
6Set Point at Min Volts 27 No No Yes Yes
7Set Point at Max Volts 27 No No Yes Yes
8On Volts 27 No No Yes Yes
9Off Differential Volts 27 No No Yes Yes
K
1Service Notification Months 27 No No Yes Yes
2Service Notification Running Time 27 No No Yes Yes
3Service Notification Cycles 27 No No Yes Yes
4Reset Maintenance Reminder 27 No No Yes Yes
5Installer Name and Phone Number 27 No No Yes Yes
SERVICE
BMS
Parameter table
Table 1-4 (continued from previous page) This table lists SMART SYSTEM control module parameters and where
to access them
NOTIFICATION

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 Amenu, or press the LEFT SELECT
[EXIT] key to return to the Amenu 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

20
Service Manual
1 Service
C: Data Logging
Reset last 10 errors
The reset last 10 errors function clears the last 10 errors log.
D: Functions
Service Mode Delay
By pressing the pin button on the front of the display for five
(5) seconds, the control will be placed in Service Mode. This
will override all other heat demands. The Service Mode
allows the installer to set the unit to either maximum firing
rate or minimum firing rate for the purpose of combustion
analysis. The delay sets the length of time the boiler will stay
in the Service Mode if no keys have been pressed before going
back to its original state. This parameter can only be changed
by the installer by accessing parameter D1. The time range of
this parameter is 0 to 30 minutes. The default value is 20
minutes.
Freeze Protection Pump On
The SMART SYSTEM control will turn on the boiler and
system pump outputs whenever the inlet temperature drops
below this setting. This is done to prevent the water in the
heat exchanger from freezing. Certain low-temperature
applications (such as snow melt) can operate at temperatures
around freezing, so this setting needs to be lowered in these
cases. The installer can adjust the temperature at which the
pump outputs are turned on by accessing parameter D2. The
minimum setting is -4°F (-20°C), and the maximum setting is
45°F (7.2°C). The default setting is 45°F (7.2°C).
Freeze Protection Burner On
If running the pumps does not prevent the inlet temperature
from falling closer to freezing, the SMART SYSTEM control
will fire the burner at low fire. The installer can adjust the
temperature at which the burner fires by adjusting parameter
D3. The minimum setting is -4°F (-20°C), and the maximum
setting is 45°F (7.2°C). The default setting is 37°F (2.8°C).
Freeze Protection Burner Differential
Once the burner has started firing due to a low inlet
temperature, the inlet temperature must increase by this
amount before the burner turns back off. The installer can
adjust this differential by accessing parameter D4. The
minimum setting is 0°F, and the maximum is 20°F. The
default setting is 5°F (2.8°C).
Display Timeout
This is the time in which the display remains illuminated.
The range is 10 seconds to 10 minutes. The default is 3
minutes.
B: Temperature Settings
Space Heating (SH1, SH2, SH3) Set Point
There are three (3) individual user set points for better zone
control. These are listed as SH1 Set Point through SH3 Set
Point. If multiple set points are calling for heat the highest set
point has priority. The range is 32°F (0°C) to 190°F (88°C).
The default is 125°F (52°C).
Space Heating (SH) Minimum Set Point
The SH minimum set point sets the minimum water
temperature set point that can be used for space heating
operation. The user or installer will not be able to program
the control with a lower SH set point. This parameter can
only be changed by the installer by accessing parameter B2.
The temperature range of this parameter is 32°F (0°C) to
190°F (88°C). The default value is 70°F (21°C).
Space Heating (SH) Maximum Set Point
The SH maximum set point sets the maximum water
temperature set point that can be used for space heating. The
user or installer will not be able to program the control with
a higher SH set point. This parameter can only be changed by
the installer by accessing parameter B3. The temperature
range of this parameter is 32°F (0°C) to 190°F (88°C). The
default value is 185°F (85°C).
SH1 - SH3 Offset Set Point
The SH offset sets how many degrees above set point the
temperature has to go before the boiler will shut off. This
parameter can only be changed by the installer by accessing
parameters B4,B7 and B10. The temperature range of these
parameters is 0°F to 20°F. The default value is 10°F.
SH1 - SH3 Differential Set Point
The SH differential sets how many degrees below the offset
the temperature has to drop before the boiler turns back on.
This parameter can only be changed by the installer by
accessing parameters B5, B8 and B11. The range is 0°F to
60°F. The default is 20°F.
3-Way Valve Time
Not used.
CAUTION Mixing valves are required for the
protection of any low temperature loops.