Hamilton Engineering XL800 Wiring diagram

INSTALLING, OPERATING & MAINTAINING
800–1500 High Eciency
Water Heaters and Heating Boilers
800–1500
795,000 BTU/hr
999,999 BTU/hr
1,475,000 BTU/hr
Do not store or use gasoline or other flammable vapors
and liquids in the vicinity of this or any other appliance.
WHAT TO DO IF YOU SMELL GAS:
• Do not try to light any appliance
• Do not touch any electrical switch
• Do not use any phone in your building
Immediately call your gas supplier from a neighbor’s
phone. Follow the gas supplier instructions. If you cannot
reach your gas supplier, call the fire department.
If the information in this manual is not
followed exactly, a fire or explosion may
result causing property damage, personal
injury or death.
WARNING
New York Massachusetts SCAQMD CEC Listed
MEA 425-05-E C1-0319-441 Compliant Rule1146.2 California Energy Commission
WARNING
These appliances MUSTbe installed by a properly licensed individual in
the City and State which the unit is being installed.All start up adjustments
and subsequent service workmust be done by a similarly licensed
contractoror a factory trained service individual. Failure to comply could
result in loss ofwarranty and or severe personal injury, death and or
substantial property damage. These instructions are required to be
kept with the appliance on the left side, in the pocket provided.
ANSI Z21.10.3/CSA 4.3-2019,
ANSI Z21.13/CSA 4.9-2017,
UL 795-2016, CGA 3.4-2020

2USING THIS MANUAL
USINGTHIS MANUAL
Throughout this manual youwill see these special attention boxes similarto those below, which are intended to
supplement the instructions and make special notice ofpotential hazards. These categories are in the judgment of
the Manufacturer.
Indicates a condition or hazard which MAY
cause severe personal injury, death, or
major property damage.
DANGER
Indicates a condition or hazard which MAY
cause severe personal injury, death, or
major property damage.
CAUTION
Indicates a condition or hazard which MAY
cause severe personal injury, death, or
major property damage.
WARNING
WARNING
• THE VENTSYSTEM IS RATEDAND DESIGNEDTO BE 2 PIPE
SEALED COMBUSTION ONLY, POLYPROPYLENE PP, PVC SCH 40
OR CPVC SCH 40 OR 80 ORAL 29-4C STAINLESSVENTING FOR
ALLMODELS. AFACTORYENGINEEREDVENTING SYSTEM MAY
ALLOW FOR EXCEPTIONS; CONSULTFACTORYFOR DETAILS.
• THIS APPLIANCE INSTALLATION MUSTCONFORMTOTHE LATEST
EDITION OFTHE “NATIONALFUELGAS CODE”ANSI Z223.1 NFPA
54 AND/OR CAN/CGAB149 INSTALLATION CODES. STATEAND
LOCALCODES MIGHTALSOAPPLYTO INSTALLATION.
• WHERE REQUIRED BYTHEAUTHORITYHAVINGJURISDICTION,
THE INSTALLATION MUSTCONFORMTOTHE STANDARDS FOR
CONTROLSAND SAFETYDEVICES FORAUTOMATICALLY FIRED
APPLIANCES, ANSI/ASME APPLIANCEAND PRESSURE VESSEL
CODE, SECTION IV,ALONGWITH CSD-1.
• THE APPLIANCE, GAS PIPING,WATER PIPING, VENTINGAND
ELECTRICALMUSTBE INSTALLED BYTRAINED & QUALIFIED
PERSONNELFAMILIAR WITH INSTALLATION PRACTICES, LOCAL
CODE,AND LICENSING REQUIREMENTS.
• IFTHE INFORMATION IN THESE INSTRUCTIONSARE NOT
FOLLOWED EXACTLY,A FIRE OR EXPLOSION MAYRESULT,
CAUSING PROPERTYDAMAGE, PERSONALINJURY, OR DEATH.
• DO NOTSTORE OR USE GASOLINE OR OTHER FLAMMABLE
VAPORSAND LIQUIDS IN THEVICINITYOFTHIS OR ANYOTHER
APPLIANCE.

3
TABLE OF CONTENTS
TABLE OF CONTENTS
USING THIS MANUAL ..................................................... 2
TABLE OF CONTENTS ......................................................3
PART 1. GENERAL INFORMATION........................ 417
A. How it Operates.....................................................................4–7
B. Appliance Controls......................................................................8
C. Appliance Control Board (Bcb) Screens...................9–10
D. Cascade Display Functions...........................................11–13
E. Glossary.........................................................................................14
F. Dimensions..........................................................................15–16
G. Pre-Installation Requirements....................................16–17
H. Pressure ReliefValve...............................................................17
PART 2. ELECTRICAL .............................................. 1821
A. Electrical Connection/Requirements...............................18
B. Internal Wiring Connection..........................................18–21
PART 3. GAS CONNECTION...................................2227
A. Gas Connection and Inspection.........................................22
B. Gas Piping....................................................................................22
C. GasTables....................................................................................23
D. Gas Valve Setup................................................................23–24
E. Setting the Maximum Load........................................25–26
F. Setting the Minimum Load..................................................26
G. Gas Conversion..........................................................................27
PART 4. VENTING ................................................... 2838
A. ApprovedVenting Materials...............................................28
B. Venting theAppliance....................................................29–36
C. InletAirVent................................................................................37
D. Venting Runs that Exceed
Maximum Combined Length...............................................37
E. Condensate Requirements..................................................38
PART 5. PIPING........................................................ 3947
A. Hydronic Heating BoilerPiping..........................................39
B. BoilerSchematic Drawings..................................................40
C. Fill & Purge Heating System.................................................41
D. Water Heating Piping.............................................................42
E. Water Heating Schematic Drawings.......................43–47
PART 6. STARTUP PROCEDURES.....................4856
A. Items tobe CheckedBefore Lighting theAppliance.....48
B. Lighting Instructions......................................................48–49
C. Operating Instructions...........................................................49
D. INI Process and Service Procedures.......................49–51
E. Adjusting theTemp on the Appliance Display...52–53
F. Sequence of Operation..........................................................54
G. 0–10v Direct Control ....................................................54–55
H. Outdoor Reset Function........................................................56
PART 7. SERVICE AND MAINTENANCE ............5763
A. Servicing theAppliance..........................................................57
B. Placing theAppliance into Normal Operation.............57
C. Testing the Manual Reset High Limit.....................57–58
D. Soft Lockout Codes........................................................59–60
E. Appliance Hard Lockout Codes..........................................61
F. To Turn O Gas to the Appliance......................................62
G. Pump & Wiring Control.........................................................62
H. Status Readings........................................................................63
I. Appliance Sensor Resistance Table.................................63
PART 8. MAINTENANCE....................................... 6466
A. Periodic MaintenanceAnd Inspections.........................64
B. Annual Inspection....................................................................65
C. Heat ExchangerAnti-Scaling Prevention Feature...66
PART 9. SPECIAL INSTALLATION REQS........... 6768
A. Installation Requirements—Massachusetts..................67
B. Installation at HighAltitudes................................................68
PART 10. PARTS BREAKDOWN........................... 6971
PART 11. WARRANTY INFORMATION...................... 72
A. Warranty Contact Information.............................................72

4PART 1. GENERAL INFORMATION
PART1. GENERALINFORMATION
A. HOW IT OPERATES
The appliance product line is a high
eciency water heating product,
requiring special venting and
condensate removal precautions.
All high eciency condensing
appliances will require more
maintenance (cleaning) than their
non-condensing counterparts.
Failure to do so may result in
damage to the appliance that is not
covered underwarranty. Failure
to follow all of the instructions
contained in this manual may also
cause premature productfailure that
may not be covered underwarranty.
This appliance has built-infreeze
protection, automatically activating
the circulation pump when the
internal water temperature drops
below 41°F. If the internal water
temperature drops to 37°F, a burn
cycle will be initiated andwill shut
down as soon as the supply water
temperature has reached 50°F.
Power and gas must be left on for
this function to operate.
The appliance’s primary controller
is the HOT™ control platform.The
HOT™ controlleruses BCB and
BDB boards to operate allfunctions
ofneeded control and safety. It
contains sophisticated logic that
allows it to operate at very precise
temperatures while minimizing
burner on/o cycling. When multiple
units are operated as a Cascade to
handle a common load, the control
logic contains the ability to control
all ofthe units as eciently as one.
Cascade operation is afactory-
installed and programmed option,
requiring a field wiring connection
between appliances for operation.
BCB=
the internal Boiler Control Board.
BDB =
the Boiler Display Board;
human interface.
CCB =
the internal Cascade Control Board.
CDB =
the Cascade Display Board, human
interface located in the face of the
cabinet.

5
PART 1. GENERAL INFORMATION
BDB—Boiler Display Board
CDB - Cascade Display Board
BCB—Boiler Control Board
CCB – Cascade Control Board
EDB – Eeprom Data Board – contains all operating parameters of CCB and BCB
TYPICAL APPLIANCE DISPLAY
AS PART OF A CASCADE
Typical Cascade display—Heating and Indirect
Hot Water applications Typical stand-alone appliance display— Heating and Indirect Hot Waterapplications
TYPICAL CASCADE DISPLAY TYPICAL STAND ALONE APPLIANCE DISPLAY
The bottom of the display contains a scrolling message related to the current status of the system (Cascade Display), or the appliance

6PART 1. GENERAL INFORMATION
As a Stand
Alone Appliance
HOT™ CONTROL
MENU NAVIGATION

7
PART 1. GENERAL INFORMATION
Appliance as
Part of a Cascade
HOT™ CONTROL
MENU NAVIGATION

8PART 1. GENERAL INFORMATION
Standby Status
Normal Operating Status in Cascade
Normal Operating Status
in single appliance
B. APPLIANCE CONTROLS
FIGURE 11
APPLIANCE CONTROL PANEL
1) POWER on/o switch
2) Display/Interface
The following components arefound on the
control panel on thefront ofthe appliance.
Press simultaneously while in SETUP area to activate Password Keyboard

9
PART 1. GENERAL INFORMATION
C. APPLIANCE CONTROL BOARD (BCB) SCREENS
In the main screen it is possible to
see:
• Set point value
• Type ofsystem (icons)
• Date and time
• Labels for navigation through the
controller(STATUS, SET POINT,
HISTORY, SETUP)
• Information and tips
• Alarms (soft lockout yellow and
hard lockout red)
Navigation and settings are allowed
by using the arrow, √ and BACK
buttons.
SLO Warning and Pump On Icon:
Stand-By Mode:
Burner On (flame icon):
HLO Warning and Pump On Icon: Entering SETUP functions area:
Operating Mode:

10 PART 1. GENERAL INFORMATION
In case offault indication (SLO or
HLO), the main page shows the
code ofthe fault occurred.To see
the extended description you have
to go into HISTORYmenu, where
a new item “ACTUALFAULT”will
be displayed. In case an appliance
RESETis required (HLO fault), it
is possible to activate the RESET
procedure entering theACTUAL
FAULTpage and selecting the
corresponding item.
HISTORY then SYSTEM INFO:
HISTORY then to view ACTUAL FAULT:
LAST 10 FAULTS (SLO):Click √ button to RESET fault:
SETUP then enter password mode:
PASSWORD entered then DONE: Options in PASSWORD MODE: Home screen during INI process:
After reaching the letter you need, press the
√ button then move to next
Press and hold simultaneously as shown
PASSWORD Keyboard:Press to enter password mode:
ACTUAL FAULT (HLO):
C. APPLIANCE CONTROL BOARD (BCB) SCREENS (continued)

11
PART 1. GENERAL INFORMATION
Flashing icon indicates demand in process (iDHW):
Standby Mode:
One or more appliances on:
STATUS/CASCADE: Sensor S2 not connectedOne or more appliances HLO:
Operating Mode (no demand):
D. CASCADE DISPLAY FUNCTIONS
Icons here indicate what
mode the appliance is in
Flame icon indicates that the appliance
is in a burn cycle—shows proof of flame
rectification

12 PART 1. GENERAL INFORMATION
D. CASCADE DISPLAY FUNCTIONS (continued)
Screen save with fault on one or more appliance:Display screen save mode:
Appliance A is the lead as indicated by the
L. The A appliance is also in a burn cycle
illustrated by the flame icon. The fan speed
is shown as a %. In common vent systems
all appliances will have a minimum fan
speed even if the appliance is not firing,
as long is there is a call for heat.
Both appliances are in a burn cycle. A is
the lead and B is 2nd in line as indicated
by the 2.

13
PART 1. GENERAL INFORMATION
Note: All temperature sensors (T1.1–T2, S1–S7) are 10k thermistors, all pressure transducers (TR1–TR5) are 5vdc.
Transducers are specific to their purpose; pressure range, accuracy and media being measured; gas, water or air/gas.
(TABLE 1-1) SENSOR TABLES
Number Sensor Part Name - Part Number Location - BCB - Boiler Control Board
T1.1 Supply temperature -Adjustable Manual Reset High
Limit TST75001 [D104920] BCB - appliance outlet pipe
T1.2 Supply temperature p/n see above,
duplex sensor BCB - appliance outlet pipe
T2 Return temperatureTST75000 [D104919] BCB - appliance header
T3* Tank for iDHW and DHW temperature
TST76110 [D122338] BCB to external component
T4* Outdoor temperatureTST 73010 [D119213] BCB to external location
T5 Flue gas temperatureTST75002 [D104921] BCB - appliance flue outlet
T6* External system water temperature
TST76110 [D122338] BCB - primary piping or Low Loss Header
TR1 Fan AirPressure transducerPTR 12323 [D104963] BCB - fan outlet
TR2 Gas Inlet pressure transducerPTR 12304 [D104962] BCB - gas valve inlet
Number Temperature Sensor Part Name Location - CCB - Cascade Control Board
S1 Cascade system sensor - linked to Pump 4 CCB - primary piping or Low Loss Header
S2 DHW recirc sensor- linked to Pump 8 CCB Supply or return to zonewith Pump 8, if the application is iDHW orDHW, it is used as the return
line sensor to control Pump 8
S3 Tank iDHWor DHW sensor- linked to Pump 5 CCB - Cascade Control Board
S4 Load/Zone sensor - linked to Pump 6 CCB Supply orreturn to zone with Pump 6
S5 Load/Zone sensor- linked to Pump 7 CCB Supply or return to zonewith Pump 7
S6 Outdoor sensor CCB to external location
S7 Load/Zone sensor - linked to Pump 9 CCB Supply or return to zone with Pump 9

14
E. GLOSSARY
PART 1. GENERAL INFORMATION
APS
Air pressure switch
BCB
Boiler Control Board
BDB
Boiler Display Board
Blocking
Limit situation is touched, boiler OFF;
when the safe situation is restored, boilerOn.
CCB
Cascade Control Board
CDB
Cascade Display Board
CH
Central Heating
Condensate
Watervaporgenerated as a product ofcombustion,
which has a low pH.
DHL
Two independent sensors (high limit and outlet water)
in a single well
iDHW
Indirect Domestic HotWater
Diverter valve
Motorized valve with spring return
DHW
Direct HotWaterproduction (instantaneous)
Hard Lock Out (HLO)
Asignificanterrororissuewith theapplianceorsystem,
suchas multiplefailuresto lightoranunsafe pressure
dierential.Anerrorcodeat thislevelwill triggera shutdown
oftheaected appliance(s).Service orrepairisrequired.
HLO
Hard Lock Out—Manual reset needed to restart the
appliance
HMI
Human Machine Interface
Hysterese
Blocking set temperature+ oset temperature—
hysterese is starting temperatureforthe boiler.
ICM
Interface Cascade Manager(with orwithout WiFi)
Indirect Tank
Sanitary hot watertank with a built in heat exchanger
often used as a component in an iDHWsystem
INI
Baseline data initialization, runs by default every 14 days
Masterless Lead-lag System
In a multi-appliance system this control systemwill work
all connected appliances as one large team.This insures
smooth distribution ofthe workload and even aging ofall
appliances connected within.
In addition, proprietary software manages common
vented systems insuring equal back-pressure on all
connected appliances and safe operation in the event
ofa component failure ofone or more ofconnected
appliances.
Modbus
ForEthernet orRS232 orRS485 bus system forLead and
Leg communication
Oset
Overriding temperature above set blocking: boilerOFF
PAVO
Zone controller
PCB
Printed circuit board—burner control board
Soft Lock Out (SLO)
Manual reset or appliance reset neededforrestart
Tank
Domestic HotWaterTank without internal heat exchanger
3-way-valve
Motorized valve: turning to the right and to the left
Parameter
Pfollowed by a letterand number(Ex: PS18 = parameter
S-18)
n.a.
Not applicable. Constant value.
TBD
To be defined
Z-INI
First INI process

15
F. DIMENSIONS
PART 1. GENERAL INFORMATION
TABLE 12 HX DATA
*At 97% thermal eciencywith 86oF incoming waterto heat exchanger
**At 95% thermal eciencywith 140oF incomingwater to heat exchanger † Individual appliancepiping pressure drop usedin thetables is basedon 20
feetofstraight pipe, 6 elbows, 2 tees, 2 full port ballvalvesand2 unions
TABLE 11 APPLIANCE DIMENSIONS
240 Volt Power Supply
Model Amps/unit Boiler Pump Total amps
Boiler
HWH 800 3.85 0.40 4.25
HWH 1000 5.1 0.48 5.58
HWH 1500 7.95 0.83 8.78
208 Volt Power Supply
Model Amps/unit Boiler Pump Total amps
Boiler
HWH 800 4.44 0.47 4.91
HWH 1000 5.88 0.55 6.44
HWH 1500 9.17 0.96 10.13
ELECTRICAL CHARACTERISTICS FOR PRODUCTS
Note: No load switching is possible directly from the BCB or CCB, it may only switch a relay signal.
Model Amps/unit Heater Pump Total amps
Boiler
HWD 800 3.85 0.83 4.68
HWD 1000 5.1 1.15 6.25
HWD 1500 7.95 1.77 9.72
Model Amps/unit Heater Pump Total amps
Boiler
HWD 800 4.44 0.96 5.40
HWD 1000 5.88 1.32 7.21
HWD 1500 9.17 2.04 11.22
Exhaust
Outlet
Gas Inlet
Height
Water Inlet
Width
B
B
C
A
Water Outlet
A
Air Intake
Length
Heater/Boiler
Model Width Height Depth A (VIC Groove) B C ShippingWeight
in mm in mm in mm in mm in mm in mm lb kg
XL800 31.6 803.2 51 1295 51 1295 2 50 6 152 1 25 650 295
XL1000 31.6 803.2 51 1295 69.2 1757.4 2 50 6 152 1 25 750 340
XL1500 31.6 803.2 51 1295 69.2 1757.4 2 50 8 203 1.5 38 850 385
Model Input Water Heater*
Output Boiler Output** Recovery @
100˚F∆T
(55.6˚C∆T)
Recovery @
80˚F∆T
(44.5˚C∆T)
Recovery @
60˚F∆T
(33.3˚C∆T)
Water Flow Rate &
Pressure Drop
DHW †
Water Flow Rate &
Pressure Drop
Heating
BTU/Hr kW BTU/Hr kW BTU/Hr kW GPH LPH GPH LPH GPH LPH GPM@FT LPM@M GPM@FT LPM@M
XL800 795,000 233 up to
771,150 up to 226 up to 755,250 up to 221 926 3,505 1,157 4,380 1,543 5,841 51.4@12' 1[email protected] 30.2@7' [email protected]
XL1000 999,999 293 up to
969,999 up to 284 up to 949,999 up to 278 1,164 4,406 1,456 5,512 1,941 7,348 64.[email protected]' [email protected] [email protected]' [email protected]
XL1500 1,475,000 432 up to
1,430,750 up to 419 up to 1,401,250 up to 410 1,718 6,494 2,147 8,115 2,863 10,822 82.9@17.3' [email protected] [email protected]' [email protected]

16 PART 1. GENERAL INFORMATION
FIGURE 12 APPLIANCES CLEARANCES
NOTE: THE APPLIANCE IS RATED AT ZERO
CLEARANCETO COMBUSTIBLES.
G. PRE-INSTALLATION REQUIREMENTS
F. DIMENSIONS (continued)
The appliance models 800–1500
are designed to be installed using a
factory designed and supplied rack or
frame. It can be installed in alcoves,
basements, and utility rooms, as
well as standard equipment rooms.
Choose a location for yourappliance,
centralized to the piping system,
along with considerationfor Electrical
(Part 2, Gas Connection (Part 3),
Venting (Part 4), and Condensate
Drain (Part 4, Section F).
The appliance rack must be level as
installed, and the mounting surface
must be designed to support the
weight (see previous page,Table 1-2
forweights). Be sure the appliance is
adequately secured to the mounting
surface.
The front coveris secured by a Hex
Head Latch. When removing the
front cover of the appliance, you
must make sure all electric power
to the appliance is turned o.
If the appliance is set up foruse on
liquefied petroleum (LP) gas, some
geographic areasfollowthe Uniform
Mechanical Code, section 304.6,
“Liquefied petroleum gas burning
appliances shall not be installed in
a pit, basement or similarlocation
where heavier-than-airgas might
collect.Appliances so fueled shall not
be installed in a below grade under-
floor space orbasement unless
such location is provided with an
approved means for removal of
unburned gas.”
Note: Awaterchemistry analysis
should be performed priorto any
installation. If thewaterquality
exceeds any ofthefollowing levels,
then a water chemistry analysis must
be performed:
• Water hardness can be no more
than 12 grains (205 ppm or mg/l)
• TDS (total dissolved solids) can
be no more than 450 ppm or
mg/l
• PH—below 6.5 or above 7.5
For total combined hardness over
15 grains (250 ppm or mg/l) or
longer pipe lengths, contact the
Manufacturer for correct pump
sizing. Combined, the hardness and
TDS can be no more than 450 ppm.
Our internal term for this is the TCH
(Total Combined Hardness).
RECOMMENDED SERVICE CLEARANCES
Ground
Minimum 6" clearance.
Recommended 24"
clearance from side of
unit (ease of access)
Recommended 6"
clearance from
side of unit (ease
of access)
32" Clearance
from front of unit
SHEET 2 OF 2
04/06/2022
Lucas Wilkins
REV
DWG.
NAME DATE
DRAWN
MATERIAL
TOLERANCES UNLESS
OTHERWISE SPECIFIED
ARMSTRONG INTERNATIONAL
FRACTIONAL 1/64
ANGULAR: 2
IN. MM
DECIMAL .XXXX .0005 -----
. XXX .005 .010
.XX .015 .10
.X ---------- .3
Copyright
C
2010 ARMSTRONG INTERNATIONAL, INC.
RELEASED
DO NOT SCALE DRAWING
DIMENSIONING
ENGLISH [mm]

Step 1—
Turn power o to unit
at power switch
17
PART 1. GENERAL INFORMATION
FIGURE 14 
This unit is supplied with a relief
valve sized in accordancewith ANSI/
ASME Heater and PressureVessel
Code, Section IV. The reliefvalve is
installed near the hot water outlet.
If thevalve supplied is replaced,
the pressure rating ofthe valve
must not exceed the listedworking
pressure ofthis appliance, and
must be rated to the proper BTU/
hr capacity of the water heater. Do
not, under any circumstances,
thread a cap or plug into the relief
valve! Explosion, serious injury or
death may result! To prevent water
damage, the reliefvalve piping must
be directed to the floor oran open
drain, but not connected directly.
There must be a 6” space between
the outlet ofreliefvalve piping and
drain orfloor. Do not hookup to drain
system directly without an airgap.
Protectfrom freezing. Place no other
valve between the reliefvalve and
the unit. Do not install any reducing
couplings orother restrictions in the
discharge line.The discharge line
must allow complete drainage ofthe
valve and line. Manually operate the
reliefvalve at least once a year.
Also, care must be exercised
when choosing the location ofthis
appliance, where leakage from the
reliefvalve, leakage from related
piping, or leakagefrom the tank
or connections, will not result in
damage to the surrounding areas,
or to the lower floors of the building.
Awaterheating appliance should
always be located in an areawith a
floor drain orinstalled in a drain pan
suitable forwaterheating appliances.
Under no circumstances, shall the
Manufacturerbe held liable forany
such water damage whatsoever.
H. PRESSURE RELIEF VALVE
Condensation Removal: This is a
condensing, high eciency appliance,
therefore condensation removal must be
addressed to avoid damage to surrounding
area or appliance. See Part 4, Section F for
Condensate Requirements.
NOTICE
Do not, under any circumstances, thread a
cap or plug into the relief valve! Explosion,
severe personal injury, death, or major
property damage may result.
WARNING
#1 TURN OFF POWER TO UNIT
Turn o powerat the breaker
supplying powerto the appliance.
In a factory supplied Cascade
package, turn o at the Intermediate
Disconnect.
Just turning o the on-o switch
on the front ofthe appliance does
not eliminate all powerfromwithin
the appliance cabinet and electrical
shock hazard still exists.
Ground
Minimum 6" clearance.
Recommended 24"
clearance from side of
unit (ease of access)
Recommended 6"
clearance from
side of unit (ease
of access)
32" Clearance
from front of unit
SHEET 2 OF 2
04/06/2022
Lucas Wilkins
REV
DWG.
NAME DATE
DRAWN
MATERIAL
TOLERANCES UNLESS
OTHERWISE SPECIFIED
ARMSTRONG INTERNATIONAL
FRACTIONAL 1/64
ANGULAR: 2
IN. MM
DECIMAL .XXXX .0005 -----
. XXX .005 .010
.XX .015 .10
.X ---------- .3
Copyright
C
2010 ARMSTRONG INTERNATIONAL, INC.
RELEASED
DO NOT SCALE DRAWING
DIMENSIONING
ENGLISH [mm]

18 PART 2. ELECTRICAL
PART2. ELECTRICAL
A. ELECTRICAL CONNECTION / REQUIREMENTS
B. INTERNAL WIRING CONNECTION
The electrical connection forthe
appliance is on the back ofthe unit.
There is a 1/2” knockout location
for an electrical connection for
the appliance’s incoming power
connection. All electrical wiring
must be performed by a qualified
licensed electrician in accordance
with National Electrical CodeANSI/
NFPAand/orthe Canadian Electrical
Code, Part 1 CSAC22.1, or to any
applicable local codes and standards.
Foryour convenience, all the points
forelectrical connections needed to
operate the appliance are labeled.
NOTE: Always check electrical
ground to known earth ground;
if less than 0.5 ohms, ground is
sucient (meter MUST be on
lowest setting).
We recommend a simplified test,
diering from one looking for
building earth ground issues, it is our
intent to use this test as an indicator
ofequipment room electrical
grounding issues, orequipment
bonding issues, not prove the earth
ground to the building.
Take an Ohm meter and place one
lead on a known earth ground (not
the groundwire on the appliance),
and place the otherlead on 1) The
near appliance system piping, 2)The
appliance heat exchanger, or3)The
appliance cabinet.
If any of those readings exceed 0.5
Ohms, then it is a good indicator
that there may be sucient stray
current flowing through thewater
in the piping system to accelerate
or amplify conditions that can cause
pump, appliance or piping issues in
the not too distant future.
If any readings are over 0.5 ohms,
an electrician should be brought in
to correct the problem.
The electrical requirements are for
standard 208–240 volt split phase,
50/60 Hz 15 Amp service.When
the unit is first powered on, there is
a self-setting ofthe electronics for
50 Hz or 60 Hz.At every power up,
the electronicswill take a couple of
seconds to compare the pulses ofthe
powerto the pulses of the crystal,
which is built into the electronics.
Then all time-related functions are
correct no matterthe power source.
The standard supplied pumps are
all 208–240 VAC, 60 cycle and are
to be wired to terminals indicated
on the appliance. In 50 cycle
applications, otherpumps may need
to be supplied, depending on water
conditions.
The incoming power shall be connected
directly to the labeled, intended
connection points only. Failure to do so
may result in an electrical short and the
control board will have to be replaced!
CAUTION
It is extremely important that this unit be
properly grounded! It is very important
that the building ground is inspected by
a qualified electrician prior to making this
connection!
DANGER
Failure to confirm propergrounding and the absence of strayvoltage may
result in premature component failure. See start up and commissioning
documents (DXXXXX–Start Up Checklist) fordetails.
Terminal G (seeAppendix) in the electrical compartment must be connected to
the building ground system.
The incoming 208–240volt split phase powersupply is connected to
terminals L1, L2, N and ground, see drawings in Part 2, Section B.
It is important that the electrical poweris not turned on at this time. Double
check all connections and then turn the power on.The display that is provided
with the appliance should now be reading the Setpoint temperature.
NOTE: See Start-Up Procedures (Part 6, Section D) to change the
temperature setting or run the appliance.

19
PART 2. ELECTRICAL
B. INTERNAL WIRING CONNECTION (continued)
XLBCB LAYOUT

20 PART 2. ELECTRICAL
FIGURE 21 .2 FIELD WIRING CONNECTIONS
A. Terminals 1 & 2
External Sensor Connection (T6)
— System temperature sensor,
senses water temp in a heating
loop.
B. Terminals 3 & 4
Outdoor Sensor (T4) — Outdoor
air sensor, set pointwill adjust
based on outdoor airtemperature
(not needed if0-10VDC output is
connected)
C. Terminals 5 & 6
0–10 VDC — Connect a
0–10 VDC output here to
vary set point temperature.
Requires a connection to each
appliance.
D. Terminals 7& 8
FaultService —Alarm bellorlight
maybe connectedhere toindicate
thatthe applianceis a hard lockout.
E. Terminals 9 & 10
Additional Heat Demand—
dry contacts that will close a
thermostat on an extra appliance
if the appliance is at 100% of
capacity.
F. Terminals11 &12
RoomThermostat — Normally
jumped. Aroom thermostat may
be connected here to enable/
disable the appliance.
G. Terminal 13–17
Cascade Connection —
Communication cables get
connected here and “daisy
chained” to all appliances in a
cascade.This is polarity sensitive.
H. Terminals 18 & 19
Tank Sensor (T3) — Sensor
forindirect or direct DHW. An
aquastat may also be connected
here.
Terminals 20 & 21
Additional Safety Circuit. On .3
models, it contains theWater
Flow Switch; the burnerdoor and
rearwall high limits in series.
I. Terminals 22 & 23
E-stop—Requires a parallel
wiring connection between
appliances back to E-stop switch
at rom wall.
B. INTERNAL WIRING CONNECTION (continued)