HTP ELU Series User manual

ELU and EFTU
High Eciency Condensing
Wall-Hung Gas Boilers
Cascade System
Installation Instructions
DANGER
!
NOTICE
The manufacturer reserves the right to make product changes or updates without notice and will not be held liable for typographical errors
in literature.
NOTE TO CONSUMER: PLEASE KEEP ALL INSTRUCTIONS FOR FUTURE REFERENCE.
272 Duchaine Blvd. New Bedford, MA 02745 www.htproducts.com
LP-743 Rev. 000 Rel. 000 Date 8.25.20
WARNING
!
Improper installation, adjustment, alteration, service, or maintenance could void product warranty and cause property damage, severe
personal injury, or death.
California Proposition 65 Warning: This product contains chemicals known to the State of California to cause cancer, birth defects, or other
reproductive harm.
The surfaces of these products contacted by potable (consumable) water contain less than 0.25% lead by weight as required by the Safe
Drinking Water Act, Section 1417.
Heat Exchanger Bears the ASME “H” Stamp
This document is provided in addition to other documentation and DOES NOT REPLACE the installation manual. This document must only be used
by a qualied installer / service technician. Read all instructions in the installation manual before installing. Then, if installing a Cascade System, read
these instructions. Only then proceed with installation. Perform steps in the given order. Failure to do so could result in substantial property damage,
severe personal injury, or death.
Included with Kit - Part #9800P-002:
Item # Description Quantity
1 BUS Connectors (p/n 8200300015201) 8
2 SYS Connector (p/n 820300014600) 1
3 System Sensor (p/n 7250-324) 1
4 Instructions (p/n LP-743) 1

LP-743 Rev. 000 Rel. 000 Date 8.25.20
2
Table of Contents
Part 1 - Cascade Water Piping
WARNING
!
Failure to follow the piping instructions in the installation manual WILL VOID the warranty and may result in property damage, severe
personal injury, or death.
Table 1 - Manifold Pipe Sizes in Inches – NOTE: The above pipe sizes are based on 20oF Delta and maximum water velocity between 5 - 6 ft/s
Model Number of Units Cascaded
2345678
ELU-85WBN 1.25” 1.5” 2” 2” 2” 2.5” 2.5”
ELU-120WBN / WCN 1.25” 1.5” 2” 2” 2” 2.5” 2.5”
ELU-150WCN 1.25” 1.5” 2” 2” 2” 2.5” 2.5”
ELU-150WBN 1.5” 2” 2” 2.5” 2.5” 3” 3”
ELU-199WBN / WCN 1.5” 2” 2” 2.5” 2.5” 3” 3”
Model Number of Units Cascaded
2345678
EFTU-85WBN 1.25” 1.5” 2” 2” 2.5” 2.5” 2.5”
EFTU-110WBN / WCN 1.5” 2” 2” 2.5” 2.5” 2.5” 3”
EFTU-150WBN / WCN 1.5” 2” 2” 2.5” 2.5” 3” 3”
EFTU-199WBN / WCN 1.5” 2” 2” 2.5” 2.5” 3” 3”
NOTE: In piping applications utilizing a single zone, it is recommended that the installer use ow / check valves with weighted seats at or near
the appliance to prevent gravity circulation.
NOTICE
Figures illustrate the basic plumbing concept of a cascade installation. Primary / Secondary is required to provide adequate ow for the
secondary circuits.
WARNING
!
The piping will not support the weight of the circulators. Refer to the circulator manufacturer’s instructions to properly support the circulator.
Failure to comply with these instructions could result in property damage, severe personal injury, or death.
NOTES:
1. These drawings are meant to show system piping concept only. Installer is responsible for all equipment and detailing required by local codes.
2. Primary / Secondary Loop: All closely spaced tees shall be within 4 pipe diameters center to center spacing.
3. A minimum of 6 pipe diameters of straight pipe shall be installed upstream and downstream of all closely spaced tees.
4. The minimum individual boiler pipe size of DHW piping should be ¾”diameter and CH piping should be 1” in diameter.
5. Circulators are shown with isolation anges. The alternative is standard anges with full port ball valves. Purge valves can be used with circulator
anges as an alternative.
6. Piping shown is Primary/Secondary.
7. Install a minimum of 12 diameters of straight pipe upstream of all circulators.
8. Unit is equipped with built-in primary pump. This pump is sized to ensure proper ow rate through the boiler heat exchanger and related
piping provided the piping is done correctly.
9. IWH Applications - a mixing valve is recommended if the DHW temperature is set above 119oF.
On Boiler Only Heating Installation
Unless a boiler is connected to an Upstream IWH, cap the DHW tting as indicated in the gures and disconnect the electrical
connection of the 3-way valve motor while the boiler is operating in central heating mode. This will lock the valve motor in central
heating mode and ensure freeze protection operates properly. Failure to disconnect the valve may disable boiler freeze protection
and result in property damage.
In mixed temperature applications, a mixing valve is required for the protection of low temperature loops.
Piping Figure Notes:
Part 1 - Cascade Water Piping 2
Part 2 - Cascade Control Set-Up 5
Part 3 - Cascade Wiring 7
Part 4 - Cascade Controls 9
A. Master Boiler Homescreen Overview 9
B. Follower Boiler Homescreen Overview 10
C. Technical Menu - Cascade Master Menu Structure 11
D. Technical Menu - Cascade Follower Menu Structure 12
E. Complete Cascade Technical Menu Parameters 13
Part 5 - Troubleshooting 19
Maintenance Notes 20
A maximum of eight (8) models may be installed in a cascade system. Installing more than the maximum amount of boilers in a cascade
system will result in system problems, property damage, and premature boiler failure. Such problems ARE NOT covered by product warranty.

LP-743 Rev. 000 Rel. 000 Date 8.25.20
3
Figure 1 - Three (3) Cascaded Boilers with Upstream or Downstream Indirect Water Heater - Piping and Wiring for ELU-85WBN, ELU-120WBN, ELU-120WCN, ELU-150WCN Models ONLY
S
TS
TS
TS
S
BUS
T B
120V
TT2
120V
OD
5V IN
120V
TNK
120V
SYS
120V
TT1
120V
PCB / CONTROL PANEL
BUS
T B
120V
TT2
120V
OD
5V IN
120V
TNK
120V
SYS
120V
TT1
120V
PCB / CONTROL PANEL
DHW
PUMP
CH
PUMP
120VAC JUNCTION BOX
DHW
PUMP
CH
PUMP
120VAC JUNCTION BOX
BUS
T B
120V
TT2
120V
OD
5V IN
120V
TNK
120V
SYS
120V
TT1 120V
PCB / CONTROL PANEL
RT
DHW
PUMP
CH
PUMP
120VAC JUNCTION BOX
OD
OD
MASTER FOLLOWER
RT
FOLLOWER
DOWNSTREAM
INDIRECT FIRED
WATER HEATER
UPSTREAM
INDIRECT FIRED
WATER HEATER
Piping for Models: ELU-85WBN, 120WBN, 120WCN, 150WCN
NOTICE
In this plumbing application, parameter 25.1.6 needs to be adjusted to setting 1. This ensures the CH pump will not operate during DHW demands.
Follow the Establishing Boilers as Master and Followers instructions when connecting to the BUS terminals. Connecting to the BUS terminals without following these instructions could damage the main PCB.

LP-743 Rev. 000 Rel. 000 Date 8.25.20
4
Figure 2 - Three (3) Cascaded Boilers with Upstream or Downstream Indirect Water Heater - Piping and Wiring for ELU-150WBN, ELU-199WBN, ELU-199WCN, and all EFTU models ONLY
S
TS
TS
TS
S
BUS
T B
120V
TT2
120V
OD
5V IN
120V
TNK
120V
SYS
120V
TT1
120V
PCB / CONTROL PANEL
BUS
T B
120V
TT2
120V
OD
5V IN
120V
TNK
120V
SYS
120V
TT1 120V
PCB / CONTROL PANEL
BUS
T B
120V
TT2 120V
OD
5V IN
120V
TNK
120V
SYS
120V
TT1
120V
PCB / CONTROL PANEL
DHW
PUMP
CH
PUMP
120VAC JUNCTION BOX
RT
DHW
PUMP
CH
PUMP
120VAC JUNCTION BOX
RT OD
OD
MASTER FOLLOWER FOLLOWER
DHW
PUMP
CH
PUMP
120VAC JUNCTION BOX
DOWNSTREAM
INDIRECT FIRED
WATER HEATER
UPSTREAM
INDIRECT FIRED
WATER HEATER
Piping for Models: ELU-150WBN, 199WBN, 199WCN EFTU-85WBN, 110WBN, 150WBN, 199WBN, 110WCN, 150WCN, 199WCN
NOTICE
In this plumbing application, parameter 25.1.6 needs to be adjusted to setting 1. This ensures the CH pump will not operate during DHW demands.
Follow the Establishing Boilers as Master and Followers instructions when connecting to the BUS terminals. Connecting to the BUS terminals without following these instructions could damage the main PCB.

LP-743 Rev. 000 Rel. 000 Date 8.25.20
5
Part 2 - Cascade Control Set-Up
When setting up a cascade system, one boiler must be congured as a Master and the other boilers must be congured as Followers.
Establishing Boilers as Master and Followers:
NOTE: Disconnect the WiFi PCB on each Follower boiler prior to setting up the cascade system. Only the Master boiler should be connected
to WiFi.
NOTE: Start with all boilers powered OFF and with no wires connected to each boiler’s BUS connection.
1. Disconnect WiFi PCBs - Permanently disconnect the WiFi PCB on each Follower boiler. Only the Master boiler can be connected to
WiFi.
2. Establish the Cascade Master - Connect power to the boiler chosen as the Master. Enter the Technical Menu and set parameter 0.4.6
= b-MAS. Connect the System Sensor at “SYS” of the Master boiler with the SYS connector. See Part 3 - Cascade Wiring. The System
Sensor and SYS connector are included in this kit.
3. Establish Followers - Connect power to the boiler chosen as Follower #1. Enter Technical Menu and set parameter 0.4.6 = b-FL1.
Repeat for remaining Follower boilers, taking care to set a unique value for each Follower, e.g. “b-FL2” through b-FL7”.
NOTE: Each Follower must have a unique address. Giving boilers the same address will result in a Conguration Conict (CONFL) error
code.
4. Establish Communication - DISCONNECT POWER TO ALL BOILERS. Daisy-chain (connect in parallel) the BUS terminal of all boilers
with the BUS connectors included in this kit. Take care to maintain the correct polarity of “B” and “T” terminals. Connect power to all
boilers.
Program the Cascade System (Master Boiler):
The following parameters must be congured at the boiler congured as the Master (0.4.6 = b-MAS).
NOTE: Set parameter 0.4.6 prior to adjusting other settings using the Establishing Boilers as Master and Followers procedure. Menu level 25
is not accessible unless 0.4.6 is set to b-MAS.
Parameter Description Value Default Setting
0.4.6 Cascade Boiler Address (Master boiler must be set to b-MAS)
UNDEF = undened, b-SIN = single boiler,
b-MAS = master boiler,
b-FL1 = Follower #1 boiler, b-FL2 = Follower #2,
b-FL3 = Follower #3, b-FL4 = Follower #4,
b-FL5 = Follower #5, b-FL6 = Follower #6,
b-FL7 = Follower #7
b--SIN
2.0.1
DHW Preheating 0 = Disabled, 1 = Enabled 1
Enables / disables DHW Comfort Function on WCN models (not applicable to WBN models) - see par. 25.2.1. NOTE: When connected
to a cascade system, DHW COMFORT Function is automatically turned on.
2.2.8
Combi Version - WCN Models - DO NOT MODIFY 0 = Combi 0
Boiler Version - WBN Models
Type of DHW control for Upstream IWH
1 = Storage with Tank Sensor
2 = Storage with Aquastat 2
Applicable when an Upstream IWH is connected directly to the Master boiler. Not applicable for WCN models.
NOTE: An Upstream IWH cannot be connected to a Master boiler when there is a Downstream / System IWH, i.e. when 25.2.2 = 1 or
2.
2.10.3
Emergency Setpoint 68-179°F 113°F
Sets Master boiler operating temperature when there is a malfunction of the BUS circuit. Can also be adjusted via the CH +/- but-
tons of the respective boiler, while operating in Emergency mode.
4.2.0 Temperature Range of CH System (Zone 1 – TT1) 0 = Low Temp (68-122°F)
1 = High Temp (86-179°F) 1
Establishes range of parameters 4.2.5 and 4.2.6. Refer to parameter 5.2.0 and 6.2.0 for CH Zone 2 and 3.
Figure 3 - Disconnect the WiFi PCB on each Follower Boiler
CN18
1
1
CN1
FUSE 5A
CN5
1
CN24
CN4
1
CN8
CN10
1
CN6
1
CN3
CN2
CN7
CN9
CN23
1CN20
1
CN12
1
CN19
1
1
CN26
CN22
CN16
BUS
T B 5V IN
OD TNK SYS TT1
TT2
120V 120V 120V120V 120V 120V
NG L
120 V AC
GATEWAY WIFI
Rd
Wh
Bl
Bl
Rd Rd
Br Br
Bl
Gry
Bl
Bk
Bk
Bk
Rd
Rd
Wh
Br
Br
Br
BkBk
Br
Wh
Water
pressure
switch
D.H.W.
temperature
sensor
D.H.W.
Flow
sensor
Flue temp.
probe
Return temp.
probe
Outlet
temp. probe
Gr
Wh
Bk
Br
Disconnect here on
every Follower boiler

LP-743 Rev. 000 Rel. 000 Date 8.25.20
6
Table 2 - Critical cascade parameters to be congured at the Master boiler. See E. Complete Cascade Technical Menu Parameters for a complete list
of parameters.
Program the Cascade System (Followers):
The following parameters must be congured at the each Follower boiler (0.4.6 = b-FL1 - 7).
NOTE: Set parameter 0.4.6 prior to adjusting other settings using the Establishing Boilers as Master and Followers procedure. Each Follower
must be set to a unique address, i.e., Follower #1 to b-FL1, Follower #2 to b-FL2, etc.
NOTE: Menu level 34 is applicable to Follower #1 (0.4.6 = b-FL1); menu levels 35 to 40 are applicable to Followers #2 to 7 respectively. For
clarity, the follow table omits menu levels 35 through 40.
Parameter Description Value Default Setting
0.4.6 Cascade Boiler Address (Follower boilers must be set to
b-FL1, 2 - 7)
UNDEF = undened,
b-SIN = single boiler,
b-MAS = master boiler,
b-FL1 = Follower #1 boiler,
b-FL2 = Follower #2,
b-FL3 = Follower #3,
b-FL4 = Follower #4,
b-FL5 = Follower #5,
b-FL6 = Follower #6,
b-FL7 = Follower #7
b--SIN
34.0.1
DHW Preheating 0 = Disabled, 1 = Enabled 1
Enables / Disables DHW Comfort Function on WCN models (not applicable to WBN models) see par. 25.2.1. NOTE: When connected
to a cascade system, DHW Comfort Function is automatically turned on.
34.2.8
Combi Version - WCN Models - DO NOT MODIFY 0 = Combi 0
Boiler Version - WBN Models
Type of DHW control for Upstream IWH
1 = Storage with Tank Sensor
2 = Storage with Aquastat 2
Applicable when an Upstream IWH is connected directly to the individual Follower boiler. Not applicable for WCN models.
Parameter Description Value Default Setting
4.2.5
Maximum CH Temperature Setting (Zone 1 – TT1) 68-122°F (when 4.2.0 = 0)
86-179°F (when 4.2.0 = 1)
120 (4.2.0 = 0)
179 (4.2.0 = 1)
Sets the maximum allowable boiler operating temperature for CH Zone 1, limiting Automatic Temperature Control and manual
adjustment from the User Menu. Refer to parameter 5.2.5 and 6.2.5 for CH Zone 2 and 3.
4.2.6
Minimum CH Temperature Setting (Zone 1 – TT1) 68-122°F (when 4.2.0 = 0)
86-179°F (when 4.2.0 = 1)
80 (4.2.0 = 0)
120 (4.2.0 = 1)
Sets the minimum allowable boiler operating temperature for CH Zone 1, limiting Automatic Temperature Control and manual
adjustment from the User Menu. Refer to parameter 5.2.6 and 6.2.6 for CH Zones 2 and 3.
25.1.6
System CH Pump Activation Logic
0 = System CH pump runs for CH and DHW
demands
1 = System CH pump only runs during CH
demands
0
For applications congured as illustrated in Figures 1 and 2, where the System CH pump must be o during DHW demands, congu-
re 25.1.6 = 1.
25.2.0
DHW Setpoint Temperature 97-140°F (Combi models)
104-140°F (Boiler models) 125
Establishes DHW temperature for the entire cascade system, including WCN boilers and Upstream IWH connected to individual
boilers. Not applicable to Downstream IWH when Master parameter 25.2.2 = 2, or to Upstream IWH connected to Follower when
parameter 34-40.2.8 = 2, or Master when parameter 2.2.8 = 2 (and 25.2.2 = 0). Also settable by pressing the DHW +/- buttons from
the home screen.
25.2.2
System DHW Mode
(Applicable to Downstream IWH)
0 = CH Only
1 = Storage with Tank Sensor
2 = Storage with Aquastat
0
With 25.2.2 = 0, the Master boiler can be congured to heat an Upstream IWH connected only to the Master boiler. In this case,
choose the DHW activation device (Tank Sensor or Aquastat) via parameter 2.2.8.
25.2.6
System DHW Charging Priority
0 = Alternating
1 = Timed Concurrent / Alternating
2 = Concurrent
0
0 = Alternating – DHW and CH will not operate simultaneously. Priority switches between DHW and CH at an interval dened by the
CH/DHW Shifting Priority Time (parameter 25.0.8); rst priority is DHW. If 25.0.8 = 0, then DHW has priority indenitely.
1 = Timed Concurrent / Alternating – DHW and CH operate simultaneously for the period dened by the CH/DHW Shifting Priority
Time (parameter 25.0.8). After the time elapses operation returns to Alternating until the end of the DHW request.
2 = Concurrent – DHW and CH can operate simultaneously indenitely.

LP-743 Rev. 000 Rel. 000 Date 8.25.20
7
Table 3 - Critical cascade parameters to be congured at each Follower boiler. See E. Complete Cascade Technical Menu Parameters for a complete
list of parameters.
Parameter Description Value Default Setting
34.10.3
Emergency Setpoint 68-179°F 113°F
Sets Follower boiler operating temperature when communication with Master is lost. Can also be adjusted via the CH +/- buttons of
the respective boiler, while operating in Emergency mode.
Part 3 - Cascade Wiring
WARNING
!
ELECTRICAL SHOCK HAZARD – To ensure safety, turn o electrical
power supply at service entrance panel before making any electrical
connections to avoid possible electric shock hazard. Failure to do so
could result in property damage, serious personal injury, or death.
Jumping out control circuits or components WILL VOID product
warranty and can result in property damage, personal injury, or
death.
Install wiring and electrically ground boiler in accordance with
the installation manual, the authority having jurisdiction or, in
the absence of such an authority, follow the National Electrical
Code, NFPA 70, and/or CSA C22.1 Electrical Code-Part 1 in Canada.
Failure to follow all applicable local, state, and national regulations,
mandates, and building supply codes for guidelines to install the
electrical power supply could result in property damage, serious
personal injury, or death.
It is of extreme importance that this unit be properly grounded. It
is very important that the building system ground is inspected by
a qualied electrician prior to making this connection. Electrical
power must only be turned on when the boiler is completely lled
with cold water. Failure to follow these instructions could result in
component or product failure, serious injury, or death.
CAUTION
!
Label all wires prior to disconnecting when servicing the boiler.
Wiring errors can cause improper and dangerous operation.
Failure to follow these instructions may result in property damage
or personal injury.
1. Connecting Power (120V) for DHW and CH Circulators
NOTE:TheCHanddownstreamIWHcirculatorsMUSTBE CONNECTED
to the Master Boiler to ensure proper operation.
To connect power for the CH and DHW external pump at the boiler
junction box:
1. Shut o the power supply at the boiler and at the circuit breaker.
2. Shut o the gas at the manual shuto.
3. Remove the boiler front cover.
4. Disconnect the three clips and open the junction box
5. Insert the circulator power cable through the hole in the side
panel; use an appropriate strain relief/conduit hub to secure the
cable to the side panel.
6. Connect the cable on the connector CN5 (CH pump) and CN4
(DHW pump). See Electrical Wiring Diagram, Figure 3.
Figure 4 - 120V Connections for DHW and CH Circulators
2. Low Voltage Wiring Connections
To access the low voltage wiring connections:
1. Shut o the power supply at the boiler and at the circuit breaker.
2. Shut o the gas at the manual shuto.
3. Remove the boiler front cover.
4. Remove the screw securing the control panel to the cross-member
(not applicable for ELU-85WBN, 120WBN, 120WCN, and 150WCN
models.
5. Push in the tabs and pull the control panel housing forward.
6. Disconnect the two clips. See Figure 4.
FUSE 5AT
POWER-IN
CN1
CN6
5NC4NC
DHW
PUMP
CH
PUMP
FUSE 5AT
N N
DHW PUMP
LN
CH PUMP
DHW PUMP
L
CH PUMP
L
NOTE: Some newer thermostat models may draw too much
power from the boiler and will require an additional power supply
to operate properly. Review the instructions provided with the
thermostat to determine if an additional power supply is needed.
Failure to do so could result in improper boiler and/or thermostat
operation.
CAUTION
DO NOT CONNECT 120V TO ANY CONTROL WIRING CONNECTION!
DOING SO WILL RESULT IN IMPROPER OPERATION AND POSSIBLE
DAMAGE TO THE BOILER. SUCH DAMAGES ARE NOT COVERED BY
PRODUCT WARRANTY!
NOTE: Figures 1 and 2 are provided as further references for wiring
cascade systems.
7. Verify that the new cable is correctly positioned inside the
control panel.
8. Reconnect the cover of the junction box.
9. Reinstall the boiler front cover
10. Restore gas to the boiler.
11. Restore power to the boiler.
Figure 5 - Releasing the Two Clips
7. Open the control panel cover to have access to the main PCB.
See Figure 5.

LP-743 Rev. 000 Rel. 000 Date 8.25.20
8
3. Wiring a Cascade System
NOTE: Disconnect the WiFi PCB on each Follower boiler prior to setting
up the cascade system. Only the Master boiler should be connected
to WiFi.
NOTE: Use the Establishing Boilers as Masters and Followers procedure,
outlined in Part 2, when connecting boilers together on the BUS.
Failure to follow these instructions will result in improper system
operation, wasted time, money, and possible property damage
and personal injury. Such damages ARE NOT covered by product
warranty.
CN1
Cascade
Connection
Outdoor
Sensor Tank temp.
probe System
Sensor
Room Thermostat
1234567
BUS
T B 5V IN
OD TNK SYS TT1
TT2
120V 120V 120V120V 120V 120V
Figure 7 - Low Voltage Wiring Connections
Ensure cascade wiring between boilers always runs from the
BUS “T” connection to the next BUS “T” connection, and BUS “B”
connection to the next BUS “B” connection. “T” to “T”; “B” to “B”.
NOTICE
Take care to route the BUS communication cables and other low
voltage wiring away from line voltage cables to avoid electrical
interference which can cause operation issues or damage the main
PCB.
Master Boiler Low Voltage Wiring
BUS
BUS Network - Communication between cascaded boilers
(up to 8) and/or HTP Room Sensors (up to 3) and/or one
HTP Multifunctional Kit. Maintain correct polarity of “B”
and “T” terminals. Use a minimum of 20 AWG cable, prefe-
rably twisted pair, up to a maximum of 164 feet.
TT2
Room Thermostat 2 - Dry contact input for System CH
Zone 2 demands. Parameters 5.1.0 through 5.7.5 are
applicable to Zone 2 demands.
NOTE: Zone 1 (TT1) demands take priority over Zone 2
(TT2) demands.
OD
Outdoor Sensor - Connect to factory provided outdoor
sensor to allow Automatic CH Temperature Control (or
connect Master boiler to WiFi and use Internet Weather).
TNK
Tank Sensor or Aquastat - Connect to a tank sensor or
Aquastat installed in a Downstream IWH heated by the
entire cascade system and set via 25.2.2. Or, installed in
an Upstream IWH connected to the Master boiler and set
via 2.2.8.
NOTE: The Master boiler cannot heat both a Downstream
and an Upstream IWH.
NOTE: If 25.2.2 = 1 or 2, the Master boiler considers the
IWH to be Downstream and uses the entire cascade to
service it - regardless of the setting of parameter 2.2.8.
SYS
System Sensor – Connect to a system sensor installed on
the supply line of the secondary loop – DO NOT INSTALL
IN PRIMARY LOOP.
NOTICE: Failure to install a system sensor will cause the
cascade system to operate in Emergency Mode.
TT1
Room Thermostat 1 – Dry contact input for System CH
Zone 1 demands. Parameters 4.1.0 through 4.7.5 are
applicable to Zone 1 demands.
NOTE: Zone 1 demands (TT1) take priority over Zone 2
(TT2) demands.
Follower Boiler Low Voltage Wiring
BUS
BUS Network - Communication between cascaded
boilers (up to 8) and/or HTP Room Sensors (up to 3) or
one HTP Multifunctional Kit. Maintain correct polarity of
“B” and “T” terminals. Use a minimum of 20 AWG cable,
preferably twisted pair, up to a maximum of 164 feet.
TT2
Auxiliary Limit Switch Input – Input does not function as
a CH Zone 2 input, but functions as a limit switch input
with parameter 34-40.2.3 = 0.
OD Not Applicable - Input does not function on Follower
boilers.
TNK
Tank Sensor or Aquastat - Connect to a tank sensor or
Aquastat installed in an Upstream IWH connected to
the respective Follower boiler. Set to Tank Sensor or
Aquastat via parameter 34-40.2.8.
SYS Not Applicable - Input does not function on Follower
boilers.
TT1 Not Applicable - Input does not function on Follower
boilers.
Figure 6 - Access to Low Voltage Wiring Connections

LP-743 Rev. 000 Rel. 000 Date 8.25.20
9
Part 4 - Cascade Controls
Figure 8 - Master Homescreen 1 - Overall System Detail
MAS Denotes
Master Boiler
Denotes a Three (3)
Boiler System
Flame Detected
with Power Level
A. Master Boiler Homescreen Overview
When viewing the Cascade Master Homescreen, the following screens
will appear on the display and alternate every three (3) seconds.
Master Homescreen 1 - Overall System Details
This screen signies that this is a master boiler with two (2) followers:
A three (3) boiler cascade system. The CASCADE text below further
lets the user know that this is a cascade system. The system is cur-
rently meeting a CH Zone 1 demand. The bars to the left and right of
the screen detail how close the DHW and CH temperatures are to the
setpoint.
Figure 9 - Master Homescreen 2 - System Temperature
SY Denotes
System Sensor
Current Temp Read
by System Sensor
Master Homescreen 2 - System Temperature
This screen displays the current temperature read by the cascade
System NTC Sensor. 138oF is displayed below.
Figure 10 - Master Homescreen 3 - Boiler Supply Temperature
bL Denotes Boiler
Supply Sensor
Current Temp Read by
Boiler Supply Sensor
Master Homescreen 3 - Boiler Supply Temperature
This screen displays the current temperature read by the master
boiler supply sensor. 150oF is displayed below.
Figure 11 - Master Homescreen 3 - Boiler O
This screen displays if the master boiler is turned o with the ON/
OFF button.
Master Homescreen 4 - Cascade Master Operating Power Level
This screen displays the current operating power level percentage
of the cascade master. A power level of 50% is displayed below.
Figure 12 - Master Homescreen 4 - Cascade Master Power Level
PL Denotes Boiler
Power Level
Current Cascade Master
Power Level Percentage
Master Homescreen 5 - Current Indirect Water Heater Tank
Temperature / Aquastat Status (of Downstream/System IWH)
This screen displays the current temperature read by a connected
DHW NTC Tank Sensor. 120oF is displayed below.
Figure 13 - Master Homescreen 5 - Current Temperature Read by DHW
Sensor
TK Denotes
DHW Tank Status
Current Temperature
Read by Sensor
This screen displays if an aquastat is connected. ON will appear if
there is a DHW demand; OFF if there is no demand.
Figure 14 - Master Homescreen 5 - Current Status of the DHW Aquastat
TK Denotes
DHW Tank Status
Current Aquastat
Status
NOTE: The screen will continue to rotate between the ve (5) ho-
mescreens. The Supply Temperature screen will indicate“blOFF”.

LP-743 Rev. 000 Rel. 000 Date 8.25.20
10
B. Follower Boiler Homescreen Overview
When viewing the display on a specic follower boiler the follow-
ing homescreens will appear and alternate every three (3) seconds.
Figure 15 - Follower Homescreen 1 - Boiler Details
b--FL Denotes
Follower Boiler
2 Denotes
Reference #
Follower Homescreen 1 - Boiler Details
This screen signies that this is a follower boiler and its reference
number is “2”.
Figure 16 - Follower Homescreen 2 - Boiler Supply Temperature
bL Denotes
Boiler Supply Sensor
Current Temp Read by
Boiler Supply Sensor
Follower Homescreen 2 - Boiler Supply Temperature
This screen displays the current temperature read by the follower
boiler supply sensor. 140oF is displayed below.
This screen displays if the follower boiler is turned o with the ON/
OFF button.
Figure 17 - Follower Homescreen 2 - Boiler O
Follower Homescreen 3 - Boiler Operating Power Level
This screen displays the current operating power level percentage of
the follower boiler. A power level of 40% is displayed below.
PL Denotes
Boiler Power Level
Current Power Level
Percentage
Figure 18 - Follower Homescreen 3 - Boiler Power Level
Follower Homescreen 4 - Indirect Water Heater Tank Temperature
/ Aquastat Status (of Upstream /Local IWH)
This screen is only displayed on the follower if it is connected to a
DHW NTC Tank Sensor or Aquastat. This screen displays the current
temperature read by a connected DHW NTC Tank Sensor. 120oF is
displayed below.
TK Denotes
DHW Tank Status
Current Temperature
Read by Sensor
This screen displays if an aquastat is connected. ON will appear if
there is a DHW demand; OFF if there is no demand.
TK Denotes
DHW Tank Status
Current Aquastat
Status
Figure 19 - Follower Homescreen 4 - Current Temperature Read by DHW
Sensor
Figure 20 - Follower Homescreen 4 - Current Status of the DHW Aquastat
NOTE: The screen will continue to rotate between the ve (5) ho-
mescreens. The Supply Temperature screen will indicate“blOFF”.

LP-743 Rev. 000 Rel. 000 Date 8.25.20
11
C. Technical Menu - Cascade Master Menu Structure
The technical menu levels and parameter selection options for
boilers congured as Master and Followers are dierent than those
congured as standalone boilers. The dierences are as follows:
Master Boiler – Retains the technical menu levels available in a
standalone boiler while adding menu level 25 for parameters speci-
c to Cascade Management. NOTE: Some parameters normally ac-
cessed via menu levels 2 and 8 for a single boiler are now accessed
via the Cascade Management menu – see below:
• Automatic Temperature Control moves from 2.2.4 to 25.1.0
• Outdoor Temperature Reading Correction: from 2.4.9 to
25.1.1
• CH Boost Interval: from 2.4.4 to 25.1.2
Figure 21 - Menu Structure
0NETWORK 25 Cascade Manager Parameters
4User Interface 0 General
2Boiler Parameters 1 System Settings
0 General 2 Domestic Hot Water
1 Free Parameters 3 System Diagnostics
2Settings 4 Cascade Diagnostics
3 Central Heating-1 5 Error History
4 Central Heating-2 6 Reset Menu
5Domestic Hot Water 34...40 Cascade Follower 1 - 7 Parameters
6 Boiler Manual Settings 0 General
7 Test & Utilities 1 Free Parameters
8 Reset Factory Settings 2 Settings
4Zone1 Parameters 3 Central Heating-1
0 Setpoint 4 Central Heating-2
1 S/W Changeover 5 Domestic Hot Water
2 Z1 Settings 6 Boiler Manual Settings
3 Z1 Diagnostics 7 Test & Utilities
7 Z1 Regulation parameters 8 Reset Factory Settings
5Zone2 Parameters 9 Other-1
0 Setpoint 10 Other-2
1 S/W Changeover 11 Boiler Statistics-1
2 Z2 Settings 12 Boiler Statistics-2
3 Z2 Diagnostics 13 Boiler
7 Z2 Regulation parameters 14 Boiler Temperature
6Zone3 Parameters 15 Storage
0 Setpoint 16 Service
1 S/W Changeover 17 Error History
2 Z3 Settings 18 Free Parameters
3 Z3 Diagnostics 42 BMS Parameters
7 Z3 Regulation parameters 0 General
8Service Parameters 1 Analog Level Settings
0 Boiler Statistics -1 2 Diagnostics
1 Boiler Statistics -2
2Boiler
3Boiler Temperature
4 Storage
5 Service
6 Error History
7Free parameters
8Reset Factory Settings
9Other - 1
10 Other - 2
11 HTP Zone Controller Parameters
0 General
1 Diagnostics
Quick Access Menus
PCB
Direct Access to the Parameters:
219, 220, 228, 229, 231 - 234, 247,
253, 257 (only when parameter 228
=1)
ERR - Fault
The display shows the last 10 errors
with the code, description, and date.
Press“+” (2) to scroll through errors
MENU
Complete menu, with access to all
parameters - see the following pages
for details.
DHW - Domestic Hot Water settings
Direct Access to the Parameters:
228
CH1 - Heating Zone 1 settings
Direct Access to the Parameters:
420, 422, 423, 425, 426, 475
CH2- Heating Zone 2 settings
Direct Access to the Parameters:
520, 522, 523, 525, 526, 575
CH3- Heating Zone 3 settings
Direct Access to the Parameters:
620, 622, 623, 625, 626, 675
MODE - Boiler working MODE
Press“+” (2) to select:
(Only DHW) -
(CH + DHW) -
(Only CH)
BMS - Building Management
System settings
Only applicable with 0-10V / 4-20mA
Clip-In Board installed
• DHW Setpoint Temperature: from 2.0.0 to 25.2.0
• DHW Comfort Function: from 2.5.0 to 25.2.1
• Anti-legionella Function: from 2.5.7 to 25.2.3
• CH Supply Setpoint (diagnostic – read only): from 8.3.0 to 25.3.0
• Outdoor Temperature (diagnostic – read only): from 8.3.5 to
25.3.2
Follower Boiler – Retains technical menu level 0 for setting the boiler
address. Loses menu levels 4, 5, and 6 normally used for managing CH
settings (Followers do not manage CH), and moves menu levels 2 and
8 to new menu level 34 (for Follower 1) [35-40 for Follower 2-7].
NOTE: The Master boiler also has access to the Follower menu of each
Follower in the cascade system.

LP-743 Rev. 000 Rel. 000 Date 8.25.20
12
D. Technical Menu - Cascade Follower Menu Structure
Figure 22 - Follower Menu Structure
0NETWORK
4User Interface
34...40 Cascade Follower 1 - 7 Parameters
0 General
1 Free Parameters
2 Settings
3 Central Heating-1
4 Central Heating-2
5Domestic Hot Water
6 Boiler Manual Settings
7 Test & Utilities
8 Reset Factory Settings
9 Other-1
10 Other-2
11 Boiler Statistics-1
12 Boiler Statistics-2
13 Boiler
14 Boiler Temperature
15 Storage
16 Service
17 Error History
18 Free Parameters
19
20
28
29
31
32
33
34
47
53 Boiler Temperature
Quick Access Menus
PCB
Direct Access to the Parameters:
34…40.19, 34…40.20, 34…40.28,
34…40.29, 34…40.31-34, 34…40.47,
34…40.53
ERR - Fault
The display shows the last 10 errors
with the code, description, and date.
Press“+” (2) to scroll through errors
MENU
Complete menu, with access to all
parameters - see the following pages
for details.

LP-743 Rev. 000 Rel. 000 Date 8.25.20
13
Menu
Sub-Menu
Parameter
Description Value
Default
Setting
E. Complete Cascade Technical Menu Parameters
ACCESS the Complete Menu
1. Simultaneously press the “+” and “-” buttons for 5 seconds. The display shows 222.
2. Press the “+” button to select 234 , the service code.
3. Press the OK button. The display shows the rst“quick setting” PCB.
4. Press the “+” button until the display shows MENU.
5. Press the OK button to access the complete menu .
2 7 7
Burning Hours Harmonization
Sets the burner run hours statistics to equal the average of the other boilers in the cascade. Used when replacing the
PCB on the Master boiler. Perform this function ONLY on the boiler where the PCB has just been replaced.
25 CASCADE MANAGEMENT
25 0 GENERAL
25 0 0 Max CH Adjustable Power Percentage 0 - 100 100
Maximum Total Cascade CH Power
25 0 1 Max DHW Adjustable Power Percentage 0 - 100 100
Maximum Total Cascade DHW Power
25 0 2 Cascade Manager Turnover Logic 0 = Minimum Switches O - On
1 = Maximum Power Division 0
25 0 3
Cascade Manager Turnover Hysteresis 0 - 20% 2
Sets the dierence in power level between switching on and switching o the next boiler. See 25.0.4 and 25.0.5.
25 0 4
Cascade Manager Min Turnover Level 0 - par. 25.0.5 (%) 20
Sets the power level threshold where the next boiler is switched o. Switches o if required power is < 25.0.4 - 25.0.3. To
avoid short-cycling, ensure 25.0.4 is set to less than half of 25.0.5 setting. Applicable only when parameter 25.0.2 = 0.
25 0 5
Cascade Manager Max Turnover Level par. 25.0.4 - 100 (%) 70
Sets the power level threshold where the next boiler is switched on. Switches on if required power is > 25.0.5. Switches
o if required power is < 25.0.5 - 25.0.3. O logic only applicable if parameter 25.0.2 = 1.
25 0 7 CH On Dierential Temperature 0 - 36oF 11
Determines how much the System temperature can drop below target before turning the cascade back on.
25 0 8 CH/DHW Shifting Priority Time 0 - 1440 minutes 45
NOTE: See 25.2.6 - System DHW Charging Priority
25 1 SYSTEM SETTINGS
25 1 0 Automatic Temperature Control 0 = OFF, 1 = ON 1
Normally managed via par. 2.2.4 for a standalone boiler.
25 1 1 Outdoor Temperature Reading Correction -5 - +5oF 0
Normally managed via par. 2.4.9 for a standalone boiler.
25 1 2
CH Boost Interval 0 - 60 (minutes) 16
Sets the time delay between the automatic adjustments of the boiler target temperature in increments of +/- 7°F (normally
managed via par 2.4.4 for a standalone boiler). Only applicable when the type of temperature control is set to Basic Temp.
Control (Parameter 4.2.1 - 5.2.1 - 6.2.1 = 1)
25 1 3
Plant Frost Protection 0 = OFF, 1 = ON 0
CH system pump operates 10 minutes every 6 hours when outdoor temp = < 25oF; operates continuously when outdoor
temp < 23oF.
25 1 5 System Pump Overrun 0 - 15 minutes or OC (On Continuously) 5
25 1 6
System Pump Activation Logic 0 - 1 1
0 = Always Active – System pump runs for CH and DHW demands
1 = Only CH – System pump only runs during CH demands

LP-743 Rev. 000 Rel. 000 Date 8.25.20
14
25 2 DOMESTIC HOT WATER - Applicable for Downstream / System IWH
25 2 0
DHW Setpoint Temperature WCN Models 97 - 140°F 125
DHW Setpoint Temperature WBN Models 104 - 140°F 125
Establishes DHW temperature for the entire cascade system, including WCN boilers and Upstream IWH connected to individual
boilers. Not applicable to Downstream IWH when Master parameter 25.2.2 = 2, or to Upstream IWH connected to Follower
when parameter 34-40.2.8 = 2, or Master when parameter 2.2.8 = 2 (and 25.2.2 = 0). Also settable by pressing the DHW +/-
buttons from the home screen.
25 2 1
DHW Comfort Function (only applicable to WCN
Models) 2 = Always On 2
Comfort function keeps the DHW heat exchanger of a WCN boiler warm when a DHW demand is not active, thereby re-
ducing the amount of time needed to heat the hot water when a demand occurs. Function activates conditionally once
per Comfort Anti-Cycling Time, par 2.5.1 on the Master boiler, par. 34-40.5.1 on Follower boilers.
To deactivate DHW Comfort Function of a Master boiler set par 2.0.1 = 0. To deactivate DHW Comfort Function at a
Follower boiler set par 34-40.0.1 = 0.
25 2 2 System DHW Mode
0 = CH Only
1 = DHW Tank NTC
2 = DHW Tank Thermostat
0
25 2 3 Anti-Legionella Function 0 = O
1 = On 0
25 2 6
System DHW Charging Priority
0 = Alternating
1 = Timed Concurrent / Alternating
2 = Concurrent
0
0 = Alternating – DHW and CH will not operate simultaneously. Priority switches between DHW and CH at an interval de-
ned by the CH/DHW Shifting Priority Time (parameter 25.0.8); rst priority is DHW. If 25.0.8 = 0, then DHW has priority
indenitely.
1 = Timed Concurrent / Alternating – DHW and CH operate simultaneously for the period dened by the CH/DHW Shi-
fting Priority Time (parameter 25.0.8). After the time elapses operation returns to Alternating until the end of the DHW
request.
2 = Concurrent – DHW and CH can operate simultaneously indenitely.
25 2 7 DHW Modulation Setpoint 68 - 179oF 179
System target temperature during a DHW demand. Not applicable for WCN models.
25 2 8
DHW On Dierential Temperature 0 - 36oF 0
Determines how much the DHW storage tank temperature can drop below target before initiating a DHW demand. Only
applicable when 25.2.2 = 1.
25 3 SYSTEM DIAGNOSTICS - READ ONLY
25 3 0 System CH Supply Setpoint Actual calculated System CH Target temperature
25 3 1 System Supply Temperature (in oF) Actual temperature read by System sensor
25 3 2 Outdoor Temperature (in oF) Only with outdoor sensor connected
25 3 3 DHW Storage Temperature (in oF) Only with NTC tank sensor connected and 25.2.2 = 1
25 3 5 System Pump Status 0 = OFF, 1 = ON
25 3 6 DHW Pump Status 0 = OFF, 1 = ON
25 4 CASCADE DIAGNOSTICS - READ ONLY
25 4 0 Cascade Power Level (in %)
25 4 1 Total Number of Cascaded Boilers
25 4 2 Available Cascaded Boilers Does not count operating or locked out boilers
25 4 3 Active Cascaded Boilers Boilers currently operating
Menu
Sub-Menu
Parameter
Description Value
Default
Setting

LP-743 Rev. 000 Rel. 000 Date 8.25.20
15
25 4 4 Cascade Manager Status
1 = Stand-by, 2 = Meeting CH Demand, 5 = CH Temperature Reached, 8 =
System Storage Loading, 9 = System Storage Loading Temp Reached, 20
= Pump Antifreeze, 21 = Burn Antifreeze, 27 = Plant Frost Protection with
Burner Blocked, 28 = System Tank Frost Protection, 29 = System Antile-
gionella Function, 30 = Chimney, 31 = Air Purge, 51 = Lockout Volatile,
72 = External Control CH Serving, 74 = External Control DHW Serving, 75
= External Control CH Temp Reached, 77 = External Control DHW Temp
Reached, 101 = Initialization
25 5 ERROR HISTORY - READ ONLY
25 5 0 Last 10 Errors Displays the Last 10 Errors
25 5 1 Reset Error List OK = Yes, ESC = No
25 6 RESET MENU
25 6 0
Automatically resets all parameters to the
factory defaults.
WARNING: Always check PCB settings
if restoring factory default settings on a
replacement controller. Replacement controllers
have generic settings that may not be specic to
the boiler model.
Reset: OK = yes, ESC = no
Only applicable to parameters in menu levels 2 and 25 of the Master boiler.
34 - 40 FOLLOWER BOILER 1 - 7
34 - 40 0 GENERAL
34 - 40 0 1 DHW Preheating 0 = Disabled, 1 = Enabled 1
Enables/disables DHW Comfort Function on WCN models (not applicable to WBN models). See par 25.2.1.
34 - 40 1 FREE PARAMETER
34 - 40 1 9
DHW Flow Detection Device Type 0 = Flow Switch, 1 = Flow Meter Varies
Default: 0 for TRX085, 120, 110C, 150C
Default: 1 for TRX150, 199, 199C, FTVN085, 110, 150, 199, 110C, 150C, 199C
WCN models use a ow meter. Not applicable for WBN models.
34 - 40 2 SETTINGS
34 - 40 2 0 Ignition Power % 0 - 100
Must be set in accordance with parameter 2.2.0 - see boiler Installation Manual.
34 - 40 2 3 TT2 Input Conguration 0 = Auxiliary Limit Switch,
1 = Room thermostat zone 2 1
NOTE: TT2 cannot work as a room thermostat input on a follower boiler.
34 - 40 2 5 NOT USED
34 - 40 2 8
WCN Models
CANNOT BE MODIFIED 0 = Combi 0
WBN Models
Type of DHW control for Indirect Hot Water
Heater (Tank Sensor or Aquastat)
0 = NOT USED
1 = Storage with Tank Sensor
2 = Storage with Aquastat
2
34 - 40 2 9 Boiler Heating Capacity (MBH) 0 - 200
Only if the PCB is changed
34 - 40 3 CENTRAL HEATING - 1
34 - 40 3 1 NOT USED
34 - 40 3 2
Absolute Max DHW power percentage
CANNOT BE MODIFIED 0 - 100
Must be set in accordance with parameter 2.3.2 - see boiler Installation Manual.
Menu
Sub-Menu
Parameter
Description Value
Default
Setting

LP-743 Rev. 000 Rel. 000 Date 8.25.20
16
Menu
Sub-Menu
Parameter
Description Value
Default
Setting
34 - 40 3 3
Absolute Min boiler power percentage
CANNOT BE MODIFIED 0 - 100
Must be set in accordance with parameter 2.3.3 - see boiler Installation Manual.
34 - 40 3 4
Absolute Max CH percentage
CANNOT BE MODIFIED 0 - 100
Must be set in accordance with parameter 2.3.4 - see boiler Installation Manual.
34 - 40 3 5 NOT USED
34 - 40 3 6 NOT USED
34 - 40 3 7 Boiler Pump Post Circulation Time (After CH) 0 - 15 minutes or OC (On Continuously) 3
34 - 40 4 CENTRAL HEATING - 2
34 - 40 4 3
CH Fan Post-Purge 0 = 2 minutes, 1 = 5 minutes 1
Default: 0 for TRX085, 120, 150, 199, 110C, 150C, 199C
Default: 1 for FTVN085, 110, 150, 199, 110C, 150C, 199C
34 - 40 4 7 Pressure Detection Device 1 = Pressure Switch 1
34 - 40 5 DOMESTIC HOT WATER (Applicable for Upstream / Local [Individual Boiler] IWH)
NOTE: Parameters 34 - 40.10.1 and 34 - 40.10.2 are also for Upstream / Local (Individual Boiler) IWH Management
34 - 40 5 1 DHW Comfort Anti-cycling Time 0 - 120 (minutes) 60
34 - 40 5 2 DHW Start Delay 5 - 200 (0.5 to 20 seconds) 5
Anti “water hammering”
34 - 40 5 3 DHW Switch O Logic 0 = anti-scale (stop at > 144°F)
1 = + 7 °F /setting 0
34 - 40 5 4
DHW Post Purge and Pump Cycle 0 = OFF, 1 = ON 1
OFF = 30 second post-circulation and 2 minute post-ventilation (or 3 minute post-circulation and 5 minute post-ventilation
if the boiler temperature requires it)
ON = When setting is ON, time for post-circulation is 3 minutes, while the time for post-ventilation is 5 minutes.
Default: 0 for TRX085, 120, 150, 199, 110C, 150C, 199C
Default: 1 for FTVN085, 110, 150, 199, 110C, 150C, 199C
34 - 40 5 5
CH Start Delay Following DHW 0 - 30 (minutes) 0
Setting is only applicable following a DHW demand from an Upstream IWH connected to the individual follower.
34 - 40 6 BOILER MANUAL SETTINGS
34 - 40 6 0 Manual mode activation 0 = OFF, 1 = ON 0
34 - 40 6 1 Boiler pump control 0 = OFF, 1 = ON 0
Set Parameter 260=1
34 - 40 6 2 Fan control 0 = OFF, 1 = ON 0
Set Parameter 260=1
34 - 40 6 3 3 way valve control 0 = DHW, 1 = Heating 0
Set Parameter 260=1
34 - 40 6 4 DHW Pump Control 0 = OFF, 1 = ON 0
34 - 40 7 TEST AND UTILITIES
34 - 40 7 0
Test Mode
TEST+ = Max Heating power
TEST+ = Max DHW power
TEST+ = Minimum power.
TEST Mode can also be activated by pressing the Reset button for 10 seconds. Test Mode deactivates after 30 minutes or
by pressing Reset.
34 - 40 7 1 Air-purge cycle 0 = OFF, 1 = ON
See First Ignition section.

LP-743 Rev. 000 Rel. 000 Date 8.25.20
17
Menu
Sub-Menu
Parameter
Description Value
Default
Setting
34 - 40 7 4 Floor drying cycle
0 = OFF
1 = Functional Heating
2 = Curing Heating
3 = Functional Heating + Curing Heating
4 = Curing Heating + Functional Heating
5 = Manual
0
34 - 40 7 5 Floor dry Supply setpoint temperature 77 - 140°F 131
34 - 40 7 7
Burning Hours Harmonization
Sets the burner run hours statistics to equal the average of the other boilers in the cascade. Used when replacing the
PCB on a Follower boiler. Perform this function ONLY on the boiler where the PCB has just been replaced.
34 - 40 8 RESET MENU
34 - 40 8 0
Automatically resets all parameters to the
factory defaults.
WARNING: Always check PCB settings
if restoring factory default settings on a
replacement controller. Replacement controllers
have generic settings that may not be specic to
the boiler model.
Reset: OK = yes, ESC = no
Only applicable to parameters in menu level 34-40 of respective Follower boiler.
34 - 40 10 OTHERS 2
34 - 40 10 0 NOT USED
34 - 40 10 1
DHW Modulation Setpoint 68 - 179oF 179
Boiler target temperature during a DHW demand. Not applicable for WCN models.
34 - 40 10 2
DHW On Dierential Temperature 0 - 36oF 0
Determines how much the DHW storage tank temperature can drop below target before initiating a DHW demand. Only
applicable when 2.2.8 = 1.
34 - 40 10 3
Emergency Setpoint 68 - 179oF 113
Sets Follower boiler operating temperature when communication with the Master is lost, or when the System Sensor is
disconnected. See Cascade Instruction Manual.
34 - 40 10 4 NOT USED
34 - 40 10 5 NOT USED
34 - 40 10 6 NOT USED
34 - 40 50 BOILER STATISTICS - 1 - READ ONLY
34 - 40 50 0 3 way valve cycles No. (n x10)
34 - 40 50 1 Boiler Pump On Hours (h x10)
34 - 40 50 2 Boiler pump cycles No. (n x10)
34 - 40 50 3 Boiler Power On Time (h x10)
34 - 40 50 4 Fan On Hours (h x10)
34 - 40 50 5 Number of fan cycles (n x10)
34 - 40 50 6 CH number of ame detections (n x10)
34 - 40 50 7 DHW number of ame detections (n x10)
34 - 40 51 BOILER STATISTICS - 2 - READ ONLY
34 - 40 51 0 CH Burner On Hours (h x10)
34 - 40 51 1 DHW Burner On Hours (h x10)
34 - 40 51 2 Number Of Flame Faults (n x10)
34 - 40 51 3 Number Of Ignition Cycles (n x10)

LP-743 Rev. 000 Rel. 000 Date 8.25.20
18
Table 4 - Complete Parameters List
Menu
Sub-Menu
Parameter
Description Value
Default
Setting
34 - 40 51 4 Average CH Cycle Length (min)
34 - 40 51 6 Number of times the Priority Timer (2.10.4) has elapsed, switching priority from DHW to CH (or vice versa).
34 - 40 52 BOILER STATISTICS - 3 - READ ONLY
34 - 40 52 1 Fan Status 0 = OFF, 1 = ON
34 - 40 52 2 Fan Speed RPM
34 - 40 52 3 Boiler Pump Status 0 = OFF, 1 or 2 = ON
34 - 40 52 4 3 Way Valve Position 0 = DHW, 1 = Central Heating
34 - 40 52 5 DHW Flow Rate (in US gpm)
Not applicable to WBN models
34 - 40 52 6 APS Status 0 = Open, 1 = Closed
34 - 40 52 8 Gas Power (kW)
34 - 40 53 BOILER TEMPERATURE - READ ONLY
34 - 40 53 1 CH Supply Temperature (in °F)
34 - 40 53 2 CH Return Temperature (in °F)
34 - 40 53 3 DHW Outlet Temperature (in °F)
Not applicable to WBN models
34 - 40 53 4 Exhaust Flue Temperature (in °F)
34 - 40 54 STORAGE - READ ONLY
34 - 40 54 0 Displays current tank temperature (in °F)
Only with NTC tank sensor connected
34 - 40 55 BOILER
34 - 40 55 0
Months to next maintenance 0 - 60 (months) 12
If enabled (8.5.1 = 1), a notication is made on the display (and via the Tele-diagnostic Service, if applicable), warning
that it is time for maintenance
34 - 40 55 1 Enable Maintenance Warning 0 = OFF, 1 = ON 0
34 - 40 55 2 Maintenance Warning Reset Reset? OK= Yes, Esc = No
Resets Maintenance Advice and clears the Warning.
34 - 40 55 4 SW Version - Display Interface
34 - 40 55 5 SW Version - Main Controller
34 - 40 55 7 Floor Drying Total Remaining Days 0 - 26 Days
34 - 40 56 ERROR HISTORY - READ ONLY
34 - 40 56 0
10 last errors ERROR 0 - ERROR 9
This parameter displays the last 10 boiler errors, indicating the error code, day, month and year of occurence.
When the parameter is accessed, the errors are listed from ERROR 0 to ERROR 9.
34 - 40 56 1 Error list reset - Clears Error History Reset? OK = yes, ESC = no
34 - 40 57 FREE PARAMETERS - READ ONLY
34 - 40 57 2 NOT USED
34 - 40 57 4 Boiler ow switch 0= OFF, 1= ON
34 - 40 57 6 Safety ame sensor 0= OFF, 1= ON
34 - 40 57 8 Boiler power level (%) 0 - 100
(0 = minimum power, 100 = maximum power)
34 - 40 57 9 Boiler Flame Signal Measured by the Control
The ame signal must exceed 18 to initially detect the
presence of ame. Flame loss is detected if the signal drops
below 15.

LP-743 Rev. 000 Rel. 000 Date 8.25.20
19
Part 5 - Troubleshooting
115
System Sensor Open Short
Circuit
1. Connect System Sensor to Master boiler SYS terminal - see Wiring a Cascade System.
2. Check cable between System Sensor and Master boiler.
3. Ensure that the System Sensor is a 10k Ohm NTC.
4. Replace System Sensor. If problem persists replace the main control.
Warning
(Auto
Reset)
150 System Sensor Overheat
Press the Reset button to clear the Error Code.
If Error happens again:
1. Check for the correct functioning and positioning of the supply and return temperature probes of
each boiler.
2. Ensure that the System Sensor is a 10k Ohm NTC.
3. Check for the correct functioning and positioning of the System Sensor - check sensor resistance vs
Sensor Temperature Resistance table in boiler Installation Manual. Replace System Sensor.
Warning
(Auto
Reset)
441
Follower Boiler Missing from
BUS Connection
Press Reset to clear the Error Code.
If Error happens again:
Check the BUS wiring. Ensure it is intact and connected. Repair if necessary.
Warning
(Manual
Reset)
CONFL Conguration Conict
Each boiler connected to the BUS must have a unique address (parameter 0.4.6). No boiler can be
congured as «b-SIN».
1. Press OK. Choose and correct the boiler address. Press OK again.
2.
If above process does not work, access parameter 0.4.6 and set the correct boiler address - see
Cascade Control Set-Up.
Blocking
(Auto
Reset)
NOAVL Boiler Address Uncongured
Boiler address is undened (0.4.6 = UNDEF).
1. Press OK. Choose and correct the boiler address. Press OK again.
2.
If above process does not work, access parameter 0.4.6 and set the correct boiler address - see
Cascade Control Set-Up.
Blocking
(Auto
Reset)
EMERG Emergency Mode
1. The Follower has been disconnected from the BUS or no longer sees the Master on the BUS - check
the BUS connections. See Wiring a Cascade System.
2. The control has sensed a short circuit on the BUS connection. Disconnect the eld wiring from the
BUS connection and conrm wiring.
3.
Verify that the BUS polarity («B» and «T» connections) is consistent on all devices connected to the
BUS.
4. If problem persists replace the main control.
NOTE: When in Emergency Mode the boiler operates in CH mode with a target boiler temperature =
Emergency Setpoint (2.10.3 for Master boiler, 34-40.10.3 for Follower boilers).
Warning
Display Description Possible Remedies Error
Type
Table 5 - Boiler Error Codes
Important
Contact a qualied service technician for assistance if a Lockout Error occurs frequently. For safety reasons, the boiler will permit a maximum
of ve (5) resets in 15 minutes (ve [5] presses of the RESET button). A sixth (6th) attempt within this 15 minute period will lock out the boiler
permanently. The boiler will only operate again after the electrical supply has been disconnected and reconnected.
Repeated Lockout Error conditions could indicate a serious error with the boiler or installation. Failure to contact a qualied service technician
to troubleshoot the error could result in substantial property damage, serious personal injury, or death.
*Error is resettable remotely via HTP Tele-Diagnostic Service, HTP Remote Contractor.
The Cascade Master can display all faults generated by the cascade system, whether the boiler is the Master or a Follower.

LP-743 Rev. 000 Rel. 000 Date 8.25.20
20
Maintenance Notes