Velocity Shadow Series User manual

High Effi ciency Gas-Fired Hot Water
Direct Vent Condensing Boilers
INSTALLATION AND OPERATING INSTRUCTIONS
These instructions must be affi xed on or adjacent to the boiler and
retained for future reference.
106916-02 - 6/16
As an ENERGY STAR® Partner, Velocity Boiler Works has determined that the
SHADOW Series meets the ENERGY STAR® guidelines for energy effi ciency
established by the United States Environmental Protection Agency (EPA).
Velocity Boiler Works, LLC
P.O. Box 14818
3633 I Street
Philadelphia, PA 19134
9700609
WARNING
Improper installation, adjustment, alteration, service or maintenance can cause property damage,
injury, or loss of life. For assistance or additional information, consult a quali ed installer, service
agency or the gas supplier. This boiler requires a special venting system. Read these instructions
carefully before installing.
VELOCITY LOGO CMYK COLORS

1
IMPORTANT INFORMATION - READ CAREFULLY
The following terms are used throughout this manual to bring attention to the presence of hazards of various risk levels,
or to important information concerning product life.
DANGER
Indicates an imminently hazardous situation
which, if not avoided, will result in death, serious
injury or substantial property damage.
CAUTION
Indicates a potentially hazardous situation
which, if not avoided, may result in moderate or
minor injury or property damage.
WARNING
Indicates a potentially hazardous situation
which, if not avoided, could result in death,
serious injury or substantial property damage.
NOTICE
Indicates special instructions on installation,
operation, or maintenance which are important
but not related to personal injury hazards.
FOLLOW ALL INSTRUCTIONS and warnings
printed in this manual, the owner’s manual and
posted on the boiler.
MAINTAIN THE BOILER. To keep your boiler safe
and efficient, have a service technician maintain
this boiler as specified in Part XIII of the manual.
IF YOU ARE NOT QUALIFIED to install or service
boilers, do not install or service this one.
THE BOILER MAY LEAK WATER at the end of
its useful life. Be sure to protect walls, carpets,
and valuables from water that could leak from the
boiler.
PROTECT YOUR HOME IN FREEZING
WEATHER. A power outage, safety lockout, or
component failure will prevent your boiler from
lighting. In winter, your pipes may freeze and
cause extensive property damage. Do not leave
the heating system unattended during cold weather
unless alarms or other safeguards are in place to
prevent such damage.
DO NOT BLOCK AIR FLOW into or around the
boiler. Insufficient air may cause the boiler to
produce carbon monoxide or start a fire.
KEEP FLAMMABLE LIQUIDS AWAY from the
boiler, including paint, solvents, and gasoline.
The boiler may ignite the vapors from the liquids
causing explosion or fire.
KEEP CHILDREN AND PETS away from hot
surfaces of the boiler, boiler piping, vent piping and
vent terminals.
CARBON MONOXIDE (CO) is an odorless, deadly
gas that may be introduced into your home by
any malfunctioning fuel-burning product or vent
system failure. Consider installing CO alarms near
bedrooms in all levels of the building to warn you
and your family of potential CO exposure.
WARNINGS FOR THE HOMEOWNER

2
DANGER
Explosion Hazard. DO NOT store or use gasoline or other ammable vapors or liquids in the vicinity of this
or any other appliance.
If you smell gas vapors, DO NOT try to operate any appliance - DO NOT touch any electrical switch or use
any phone in the building. Immediately, call the gas supplier from a remotely located phone. Follow the
gas supplier’s instructions or if the supplier is unavailable, contact the re department.
WARNING
• Asphyxiation Hazard. This boiler requires regular maintenance and service to operate safely.
Follow the instructions contained in this manual.
• Improper installation, adjustment, alteration, service or maintenance can cause property damage,
personal injury or loss of life. Read and understand the entire manual before attempting installation,
start-up operation, or service. Installation and service must be performed only by an experienced,
skilled, and knowledgeable installer or service agency.
• This boiler must be properly vented.
• This boiler needs fresh air for safe operation and must be installed so there are provisions for
adequate combustion and ventilation air.
• Asphyxiation Hazard. The interior of the venting system must be inspected and cleaned before the
start of the heating season and should be inspected periodically throughout the heating season for
any obstructions. A clean and unobstructed venting system is necessary to allow noxious fumes
that could cause injury or loss of life to vent safely and will contribute toward maintaining the
boiler’s efciency.
• Installation is not complete unless a safety relief valve is installed into the supply piping
immediately downstream of the boiler. - See the Water Piping and Trim Section of this manual for
details.
• This boiler is supplied with safety devices which may cause the boiler to shut down and not re-start
without service. If damage due to frozen pipes is a possibility, the heating system should not be
left unattended in cold weather; or appropriate safeguards and alarms should be installed on the
heating system to prevent damage if the boiler is inoperative.
• Burn Hazard. This boiler contains very hot water under high pressure. Do not unscrew any pipe
ttings nor attempt to disconnect any components of this boiler without positively assuring the
water is cool and has no pressure. Always wear protective clothing and equipment when installing,
starting up or servicing this boiler to prevent scald injuries. Do not rely on the pressure and
temperature gauges to determine the temperature and pressure of the boiler. This boiler contains
components which become very hot when the boiler is operating. Do not touch any components
unless they are cool.
• Respiratory Hazard. Boiler materials of construction, products of combustion and the fuel contain
alumina, silica, heavy metals, carbon monoxide, nitrogen oxides, aldehydes and/or other toxic or
harmful substances which can cause death or serious injury and which are known to the state of
California to cause cancer, birth defects and other reproductive harm. Always use proper safety
clothing, respirators and equipment when servicing or working nearby the appliance.
• Failure to follow all instructions in the proper order can cause personal injury or death. Read all
instructions, including all those contained in component manufacturers manuals which are provided
with the boiler before installing, starting up, operating, maintaining or servicing.
• All cover plates, enclosures and guards must be in place at all times.

3
Table of Contents
I. Product Description 4
 II.  Specications      4
III. Before Installing 5
IV. Locating The Boiler 6
V. Mounting The Boiler 7
VI. Air For Ventilation 8
VII. Venting 11
A. General Vent System Design 11
B. Design Requirements Unique to Horizontal Twin Pipe
Venting Systems 17
C. Design Requirements Unique to Vertical Venting Systems 22
D. Design Requirements Unique to Split Vent Systems 25
E. Assembly of CPVC/PVC Vent Systems 27
F. Condensate Trap and Drain 34
G. Removing An Existing Boiler From Common Chimney 35
VIII. Gas Piping 36
IX. System Piping 38
A. General System Piping Precaution 38
B. Near Boiler Piping Design 39
C. Standard Piping Installation Requirements 44
D. Piping For Special Situations 45
X. Wiring 47
XI. Start-up and Checkout 55
XII. Operation 62
XIII. Service and Maintenance 69
XIV. Troubleshooting 75
XV. Parts 83
Appendix A: LP Gas Conversion Instructions 93
Appendix B: Special Requirements For Side-Wall 97
Vented Appliances In The Commonwealth
of Massachusetts
Appendix C: Control Set-up Using PIM 99

4
II Specications
FIGURE 2.1: GENERAL CONFIGURATION
I Product Description
Thisboilerisastainlesssteelgasredcondensingboilerdesignedforuseinforcedhotwaterheatingsystemsrequiring
supply water temperatures of 180°F or less. It is designed for installation on a wall. This boiler may be vented vertically
orhorizontallywithcombustionairsuppliedfromoutdoors.Itisnotdesignedforuseinsystemscontainingsignicant
amounts of dissolved oxygen.

5
Table2.2:Specications
SHADOW Series
AHRI Ratings OtherSpecications
MODEL*
MAXIMUM
INPUT
(MBH)
MINIMUM
INPUT
(MBH)
HEATING
CAPACITY
(MBH)
NET AHRI
RATING*
(MBH)
AFUE
(%)
WATER
VOLUME
(Gal.)
VENT
COLLAR
DIA.
SUPPLY &
RETURN
CONNECTION
SIZE (NPT)
GAS
CONNECTION
SIZE (NPT)
APPROX.
NET
WEIGHT
(lb)
SHADW080 80 16 74 64 94.0 0.36 2” 1” 1/2” 81
SHADW100 100 20 92 80 93.3 0.44 2” 1” 1/2” 83
SHADW120 120 24 112 97 94.0 0.53 3” 1” 1/2” 86
SHADW150 150 30 142 123 95.0 0.79 3” 1” 1/2” 111
SHADW180 180 36 170 148 94.0 0.79 3” 1” 1/2” 111
* The Net AHRI Water Ratings shown are based on a piping and pickup allowance of 1.15. The manufacturer should be consulted before selecting
a boiler for installations having unusual piping and pickup requirements, such as intermittent system operation, extensive piping systems, etc.
Table 2.3: Vent Lengths
MODEL
NOMINAL
VENT/INTAKE
SIZE (in)
MIN VENT
LENGTH (in)
MAX VENT
LENGTH
APPROX.
DERATE AT
MAX VENT
(%)
SHADW080
2
12
60ft
9
SHADW080*
3
12
135ft
2
SHADW100
2
12
60ft
15
SHADW100*
3
12
135ft
3
SHADW120
3
12
135ft
7
SHADW150
3
52
135ft
7
SHADW180
3
52
135ft
9
See Part VII (Venting) for additional requirements and details.
*Vent/Intake size increased from 2” to 3” at boiler connections.
III Before Installing
1) Safe, reliable operation of this boiler depends upon installation by a professional heating contractor in strict accordance
with this manual and the requirements of the authority having jurisdiction.
 • Intheabsenceofanauthorityhavingjurisdiction,installationmustbeinaccordancewiththismanual 
and the National Fuel Gas Code, ANSI Z223.1. In Canada, installation must be in accordance with the B149.1
Installation Code.
 • Whererequiredbytheauthorityhavingjurisdiction,thisinstallationmustconformtotheStandard for Controls
and Safety Devices for Automatically Fired Boilers (ANSI/ASME CSD-1).
2) Read Section VII to verify that the maximum combustion air and exhaust pipe lengths will not be exceeded in the
planned installation. Also verify that the vent terminal can be located in accordance with Section VII.
3) Make sure that the boiler is correctly sized:
• Forheatingsystemsemployingconvectionradiation(baseboardorradiators),useanindustryacceptedsizing
method such as the I=B=R Guide RHH published by the Air-Conditioning, Heating and Refrigeration Institute
(AHRI).
• Fornewradiantheatingsystems,refertotheradianttubingmanufacturer’sboilersizingguidelines.
• Forsystemswhichincludeanindirectwaterheater,makesuretheboilerhastheoutputcalledforbytheindirect
waterheatermanufacturer’sinstructions.

6
4) Allboilersareshippedfromthefactoryconguredforusewithnaturalgas.TheymaybeconvertedforusewithLPgas
(“propane”) using a combustion analyzer in accordance with the instructions in Appendix A.
5) Models are not suitable for installation at altitudes above 2000ft.
IV Locating the Boiler
1) Observe the minimum clearances shown in Figure 4.1. These clearances apply to combustible construction as well as non-
combustiblewalls,oors,ceilingsanddoors.
2) Note the recommended service clearances in Figure 4.1. These service clearances are recommended, but may be reduced to
the combustible clearances provided:
a. Access to the front of the boiler is provided through a door.
b. Access is provided to the condensate trap located beneath the boiler.
 Notethatservicingtheboilerwillbecomeincreasinglydifcultastheseserviceclearancesarereduced.
3) Observe the following clearances from piping to combustible construction:
Non-concentric vent (exhaust): ¼”
Air intake piping: 0”
Hot water piping: ¼”
4) The relief valve and gauge must be installed in the location shown in Figure 2.1 and must be in the same space as the boiler.
5) The boiler should be located so as to minimize the length of the vent system.
6) The combustion air piping must terminate where outdoor air is available for combustion and away from areas that will con-
taminatecombustionair.Avoidareasnearchemicalproductscontainingchlorine,chloridebasedsalts,chloro/uorocarbons,
paint removers, cleaning solvents and detergents.
NOTICE
This product must be installed by a licensed plumber or gas tter when
installed within the Commonwealth of Massachusetts. See Appendix B for
additional important information about installing this product within the
Commonwealth of Massachusetts.
DANGER
• Do not attempt to operate this boiler on LP gas without converting it in accordance with the
instructions shown in Appendix A.
• Do not attempt to convert this boiler to LP gas without the use of a combustion analyzer.
• Failure to follow the conversion instructions in Appendix A will result in operation of the boil-
er at unsafe Carbon Monoxide (CO) levels and may result in personal injury or loss of life.
Improper conversion may also result in unreliable operation, resulting in property damage.
WARNING
Do not install this boiler at altitudes above 2000ft. Attempting to do so may result in unreliable
operation, property damage, personal injury or loss of life.

7
Figure 4.1: Minimum Clearances To Combustible Construction
V Mounting The Boiler
CAUTION
This boiler weighs as much as 111 pounds:
• Two people are required to safely lift this boiler onto the wall mounting hook.
• Make sure that wall mounting hook is anchored to a structure capable of
supporting the weight of the boiler and attached piping when  lled with water.
Jurisdictions in areas subject to earthquakes may have special requirements
for supporting this boiler. These local requirements take precedence over the
requirements shown in this section.

8
1) If the boiler is installed on a framed wall, minimum acceptable framing is 2 x 4 studs on 16” centers. The boiler mount-
ing holes are on 16” centers for installation between two studs at the standard spacing. In cases where the boiler cannot
be centered between the studs, or where the studs are spaced closer than 16” apart, the boiler may be anchored to ¾”
plywood or horizontal 2 x 4s anchored to the studs.
2) 5/16” x 2” lag screws and washers are provided for mounting this boiler. These lag screws are intended for mounting the
boiler directly onto studs covered with ½” sheathing. When the boiler is attached to other types of construction, such as
masonry, use fasteners capable of supporting the weight of the boiler and attached piping in accordance with good con-
struction practice and applicable local codes.
3) Make sure that the surface to which the boiler is mounted is plumb.
4) Before mounting the boiler, make sure that wall selected does not have any framing or other construction that will inter-
fere with the vent pipe penetration.
5) Onceasuitablelocationhasbeenselectedfortheboiler,andanyneededmodicationshavebeenmadetothewall,use
Figure 5.1 to locate holes “A” and “B”. Make sure that the horizontal centerline of these holes is level. Holes “C” and
“D” may also be drilled at this time or after the boiler is hung on the wall. If the 5/16” x 2” lag screws are used, drill
3/16” pilot holes.
6) The wall mounting hook is used to secure the boiler to the shipping pallet. Remove this hook from the pallet and secure
to the wall using the 5/16” x 2” lag screws and washers, or other suitable anchors as appropriate (Figure 5.2). Make sure
the hook is level.
7) Hang the boiler on the wall hook as shown in Figure 5.2.
8) IfnotalreadydoneinStep(5)locateanddrillholes“C”and“D”usingtheobroundslotsinthebottommountingange.
Securethebottomangetothewallusingthe5/16”x2”lagscrews,orotherfastenersasappropriate(Figure5.2).
9) Verify that the front of the boiler is plumb. If it is not, install washers at holes “C” and “D” between the bottom mounting
angeandthewalltoadjust.
VI Air for Ventilation
Air for combustion must always be obtained directly from outdoors (see Section VII for intake piping). Although com-
bustion air must always be obtained directly from outdoors, ventilation openings may still be required to prevent overheat-
ing of boiler components if the boiler is installed in a small space, such as a closet.
 • IftherecommendedserviceclearancesshowninFigure4.1canbemaintained(withalldoorstotheroom 
closed), no ventilation openings are required for this boiler.
 • Iftheaboveserviceclearancescannotbemaintained,providetwoopeningsintotheroom,onenear 
  theoorandoneneartheceiling.Thetopedgeoftheupperopeningmustbewithin12”oftheceiling 
  andthebottomedgeoftheloweropeningwithin12”oftheoor.Eachoftheseopeningsmusthavea 
free area of at least 100 square inches. The “free area” takes into account the blocking effect of mesh
  grillesandlouvers.Wherescreensareusedtheymustbenonerthan¼”(4x4)mesh.
 • Ifthisboilerisinstalledinaroomwithotherappliances,provideadequateairforcombustionand/or
  ventilationinaccordancewiththeotherappliancemanufacturer’sinstallationmanualorapplicablecode. 
In cases where such provisions require two openings in excess of 100 square inches, no additional
opening area is required for this boiler.
WARNING
Outdoor combustion air must be piped to the air intake. Never pipe combustion air from
areas containing contaminates such as swimming pools and laundry room exhaust
vents. Contaminated combustion air will damage the boiler and may cause property
damage, personal injury or loss of life.

9
Figure 5.1 Wall Layout/Mounting Hole Location