Alpine ALP150B Service manual

103448-07 - 1/16 Price - $5.00
As an ENERGY STAR®Partner, U.S. Boiler Company has determined that the Alpine™ Series meets the ENERGY
STAR® guidelines for energy efciency established by the United States Environmental Protection Agency (EPA).
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.
9700609
INSTALLATION, OPERATING AND
SERVICE INSTRUCTIONS FOR
ALPINE™
CONDENSING HIGH EFFICIENCY
DIRECT VENT
GAS - FIRED HOT WATER BOILER
Size Range - 80 MBH through 285 MBH

2 103448-07- 1/16
IMPORTANT INFORMATION - READ CAREFULLY
NOTE: The equipment shall be installed in accordance with those installation regulations enforced in the area where the
installation is to be made. These regulations shall be carefully followed in all cases. Authorities having jurisdiction
shall be consulted before installations are made.
All wiring on boilers installed in the USA shall be made in accordance with the National Electrical Code and/or local regulations.
All wiring on boilers installed in Canada shall be made in accordance with the Canadian Electrical Code and/or local regulations.
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.
The City of New York requires a Licensed Master Plumber supervise the installation of this product.
The Massachusetts Board of Plumbers and Gas Fitters has approved the Alpine™ Series boiler. See the Massachusetts Board of
Plumbers and Gas Fitters website, http://license.reg.state.ma.us/pubLic/pl_products/pb_pre_form.asp for the latest Approval
Code or ask your local Sales Representative.
The Commonwealth of Massachusetts requires this product to be installed by a Licensed Plumber or Gas Fitter.
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.
DANGER
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, NO 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.

103448-07 - 1/16 3
Special Installation Requirements for Massachusetts
A. For all sidewall horizontally vented gas fueled equipment installed in every dwelling, building or structure used in whole or
in part for residential purposes and where the sidewall exhaust vent termination is less than seven (7) feet above grade, the
following requirements shall be satised:
1. If there is no carbon monoxide detector with an alarm already installed in compliance with the most current edition of
NFPA 720, NFPA 70 and the Massachusetts State Building Code in the residential unit served by the sidewall horizontally
vented gas fueled equipment, a battery operated carbon monoxide detector with an alarm shall be installed in compliance
with the most current edition of NFPA 720, NFPA 70 and the Massachusetts State Building Code.
2. In addition to the above requirements, if there is not one already present, a carbon monoxide detector with an alarm
and a battery back-up shall be installed and located in accordance with the installation requirements supplied with the
detector on the oor level where the gas equipment is installed. The carbon monoxide detector with an alarm shall
comply with 527 CMR, ANSI/UL 2034 Standards or CSA 6.19 and the most current edition of NFPA 720. In the event
that the requirements of this subdivision can not be met at the time of the completion of the installation of the equipment,
the installer shall have a period of thirty (30) days to comply with this requirement; provided, however, that during
said thirty (30) day period, a battery operated carbon monoxide detector with an alarm shall be installed in compliance
with the most current edition of NFPA 720, NFPA 70 and the Massachusetts State Building Code. In the event that the
sidewall horizontally vented gas fueled equipment is installed in a crawl space or an attic, the carbon monoxide detector
may be installed on the next adjacent habitable oor level. Such detector may be a battery operated carbon monoxide
detector with an alarm and shall be installed in compliance with the most current edition of NFPA 720, NFPA 70 and the
Massachusetts State Building Code.
3. A metal or plastic identication plate shall be permanently mounted to the exterior of the building at a minimum height
of eight (8) feet above grade directly in line with the exhaust vent terminal for the horizontally vented gas fueled
heating appliance or equipment. The sign shall read, in print size no less than one-half (1/2) inch in size, “GAS VENT
DIRECTLY BELOW. KEEP CLEAR OF ALL OBSTRUCTIONS”.
4. A nal inspection by the state or local gas inspector of the sidewall horizontally vented equipment shall not be performed
until proof is provided that the state or local electrical inspector having jurisdiction has granted a permit for installation of
carbon monoxide detectors and alarms as required above.
B. EXEMPTIONS: The following equipment is exempt from 248 CMR 5.08(2)(a) 1 through 4:
1. The equipment listed in Chapter 10 entitled “Equipment Not Required To Be Vented” in the most current edition of NFPA
54 as adopted by the Board; and
2. Product Approved sidewall horizontally vented gas fueled equipment installed in a room or structure separate from the
dwelling, building or structure used in whole or in part for residential purposes.
C. When the manufacturer of Product Approved sidewall horizontally vented gas equipment provides a venting system design
or venting system components with the equipment, the instructions for installation of the equipment and the venting system
shall include:
1. A complete parts list for the venting system design or venting system; and
2. Detailed instructions for the installation of the venting system design or the venting system components.
D. When the manufacturer of a Product Approved sidewall horizontally vented gas fueled equipment does not provide the parts
for venting ue gases, but identies “special venting systems”, the following shall be satised:
1. The referenced “special venting system” instructions shall be included with the appliance or equipment installation
instructions; and
2. The “special venting systems” shall be Product Approved by the Board, and the instructions for that system shall include a
parts list and detailed installation instructions.
E. A copy of all installation instructions for all Product Approved sidewall horizontally vented gas fueled equipment, all venting
instructions, all parts lists for venting instructions, and/or all venting design instructions shall remain with the appliance or
equipment at the completion of the installation.

4 103448-07- 1/16
TABLE OF CONTENTS
I. Product Description, Specications and Dimensional Data...................... 5
II. Unpacking Boiler........................................................................................ 9
III. Pre-Installation and Boiler Mounting ........................................................ 10
IV. Venting...................................................................................................... 17
A. General Guidelines............................................................................... 18
B. CPVC/PVC Venting.............................................................................. 22
C. Polypropylene Venting......................................................................... 35
D. Stainless Steel Venting........................................................................ 43
E. Removing the Existing Boiler............................................................... 48
F. Multiple Boiler Installation Venting....................................................... 50
V. Condensate Disposal................................................................................. 52
VI. Water Piping and Trim............................................................................... 54
VII. Gas Piping ............................................................................................... 70
VIII. Electrical ................................................................................................... 74
IX. System Start-up ....................................................................................... 88
1. Operation...................................................................................................... 96
A. Overview............................................................................................... 96
B. Supply Water Temperature Regulation................................................ 97
C. Boiler Protection Features.................................................................... 98
D. Multiple Boiler Control Sequencer........................................................ 99
E. Boiler Sequence of Operation.............................................................. 100
1. Normal Operation........................................................................... 100
2. Using The Display.......................................................................... 101
3. Status Screens.............................................................................. 102
4. Detail Screens............................................................................... 104
5. Multiple Boiler Sequencer Screens................................................ 105
F. Changing Adjustable Parameters........................................................ 106
1. Entering Adjust Mode.................................................................... 106
2. Adjusting Parameters..................................................................... 107
XI. Service and Maintenance ........................................................................ 124
XII. Troubleshooting........................................................................................ 131
XIII. Repair Parts ............................................................................................. 136
Appendix A - Figures................................................................................ 146
Appendix B - Tables.................................................................................. 149

103448-07 - 1/16 5
I. Product Description, Specications and Dimensional Data
Alpine™ Series boilers are condensing high efciency
gas-red direct vent hot water heating boilers designed
for use in forced hot water space or space heating with
indirect domestic hot water heating systems, where supply
water temperature does not exceed 210°F. These boilers
have special coil type stainless steel heat exchangers,
constructed, tested and stamped per Section IV ‘Rules
for Construction of Heating Boilers’ of ASME Boiler and
Pressure Vessel Code, which provide a maximum heat
transfer and simultaneous protection against ue gas product
corrosion. These boilers are not designed for use in gravity
hot water space heating systems or systems containing
signicant amount of dissolved oxygen (swimming pool
water heating, direct domestic hot water heating, etc.).
Dimension Boiler Model
ALP080B (1) ALP105B (1) ALP150B (1) ALP210B (1) ALP285B (2)
A - Inch
(mm)
12-9/16
(320)
14
(356)
19-11/16
(500)
23-15/16
(608)
21-13/16
(554)
B - Inch
(mm)
5-5/8
(142)
5-13/16
(147)
7-5/16
(185)
C - Inch
(mm)
7-5/16
(186)
14-1/8
(358)
D - Inch
(mm)
9-5/16
(237)
10-3/4
(273)
16-7/16
(417)
17-1/8
(435)
18
(456)
E - Inch
(mm)
5-15/16
(151)
12-1/4
(312)
Gas Inlet F
(FPT) 1/2” 3/4”
Return G
(FPT) 1” 1-1/4”
Supply H
(FPT) 1” 1-1/4”
Condensate Drain J * * Factory Provided Socket End Compression Pipe Joining Clamp
for 3/4” Schedule 40 PVC Pipe
Boiler Two-Pipe
CPVC/PVC Vent Connector
(Figs. 1A, 1C) - Inch
3 x 3 3 x 4 4 x 4
Boiler
CPVC Vent Connector/Pipe
(Fig. 1B) - Inch
3” N/A
Boiler Inlet Air Connector
(Fig. 1B) - Inch 3” 3” 4” 4” N/A
Table 1B: Dimensional Data (See Figures 1A, 1B, 1C)
NOTES:
(1) - These boiler models available as either Floor mounted (sufx F) or, Wall mounted (sufx W).
(2) - This boiler model available as Floor mounted (sufx F) only.
Specication Boiler Model
ALP080B ALP105B ALP150B ALP210B ALP285B
Altitude (ft. above sea level) 0-4500 0-4500 0-4500 0-4500 0-4500
Fuel Shipped for Natural Gas, Field Converted for LP Gas
Max. Allowable Water Temperature (°F) 210
Max. Allowable Working Pressure (psi) 160
Factory supplied Safety Relief Valve (psi) * 30
Boiler Water Volume (gal.) 0.6 0.7 1.3 1.7 2.4
Heat Transfer area (sq. ft.) 7.3 9.1 16.4 21.8 29.1
Approx. Shipping weight (lb.) 137 155 182 206 256
Table 1A: Specications
* Optional 50 psi, 80 psi and 100 psi safety relief valves are available for all models.

6 103448-07- 1/16
Figure 1A: Models ALP080B through ALP210B (Floor Mounted)
I. Product Description, Specications and Dimensional Data (continued)

103448-07 - 1/16 7
Figure 1B: Models ALP080B through ALP210B (Wall or Floor Mounted)
I. Product Description, Specications and Dimensional Data (continued)

8 103448-07- 1/16
Figure 1C: Model ALP285B (Floor Mounted)
I. Product Description, Specications and Dimensional Data (continued)

103448-07 - 1/16 9
Table 2: Ratings
I. Product Description, Specications and Dimensional Data (continued)
Alpine Series Gas-Fired Boilers
Model Number Input (MBH) Heating Capacity
(MBH)
Net AHRI Ratings Water 1
(MBH)
AFUE
(%)
Min. Max.
ALP080B 16 80 72 63 95
ALP105B 21 105 96 83 95
ALP150B 30 150 136 118 95
ALP210B 42 210 194 169 95
ALP285B 57 285 262 228 95
Ratings shown are for installations at sea level and elevations up to 2000 ft. For elevations above 2000 ft., the boiler will
naturally derate by 2.5% for each 1000 ft. above sea level - applicable to ALP080B thru ALP210B.
ALP285B rating is for installation at sea level and elevations up to 7800 ft. For elevations above 7800 ft., the boiler will
naturally derate by 1.8% for each 1000 ft. above sea level.
1 Net AHRI Water Ratings based on allowance of 1.15. Consult manufacturer before selecting boiler for installations
having unusual piping and pickup requirements, such as intermittent system operation, extensive piping systems, etc.
II. Unpacking Boiler
CAUTION
Do not drop boiler.
A. Move boiler to approximate installed position.
B. Remove all crate fasteners.
C. Lift and remove outside container.
D. Remove boiler from cardboard positioning sleeve on
shipping skid.
WARNING
Installation of this boiler should be undertaken
only by trained and skilled personnel from a
qualied service agency.
E. Move boiler to its permanent location.

10 103448-07- 1/16
WARNING
Explosion Hazard. Asphyxiation Hazard.
Electrical Shock Hazard. Installation of this
boiler should be undertaken only by trained
and skilled personnel from a qualied service
agency. Follow these instructions exactly.
Improper installation, adjustment, service,
or maintenance can cause property damage,
personal injury or loss of life.
NOTICE
Due to the low water content of the boiler, mis-
sizing of the boiler with regard to the heating
system load will result in excessive boiler
cycling and accelerated component failure. U.S.
Boiler Company DOES NOT warrant failures
caused by mis-sized boiler applications. DO
NOT oversize the boiler to the system. Multiple
boiler installations greatly reduce the likelihood
of boiler oversizing.
WARNING
Asphyxiation Hazard.
Models with Two-Pipe Vent Connector:
Apply supplied dielectric grease to gasket inside
vent section of two-pipe vent connector. Failure
to apply the grease could result in ue gas leaks
from gasket rupture during vent pipe installation
or gasket deterioration due to condensate
exposure.
A. Installation must conform to the requirements
of the authority having jurisdiction in or, in the absence
of such requirements, to the National Fuel Gas Code,
ANSI Z223.1/NFPA 54, and/or Natural Gas and
Propane Installation Code, CAN/CSA B149.1.
Where required by the authority having jurisdiction, the
installation must conform to the Standard for Controls
and Safety Devices for Automatically Fired Boilers,
ANSI/ASME CSD1.
B. Boiler is certied for installation on
combustible ooring. Do not install boiler on
carpeting.
C. Provide clearance between boiler jacket and
combustible material in accordance with local re
ordinance. Refer to Figure 2A or 2B for minimum listed
clearances from combustible material. Recommended
service clearance is 24 in. (610 mm) from left side,
III. Pre-Installation and Boiler Mounting
front, top and rear of the boiler. Recommended front
clearance may be reduced to the combustible material
clearance providing:
1. Access to boiler front is provided through a door
or removable front access panel.
2. Access is provided to the condensate trap
located underneath the heat exchanger.
3. Access is provided to thermal link located at
boiler rear.
D. Protect gas ignition system components
from water (dripping, spraying, rain, etc.) during
boiler operation and service (circulator replacement,
condensate trap, control replacement, etc.).
E. Provide combustion and ventilation air in
accordance with applicable provisions of local building
codes, or: USA - National Fuel Gas Code, ANSI
Z223.1/NFPA 54, Air for Combustion and Ventilation;
Canada - Natural Gas and Propane Installation Code,
CAN/CSA-B149.1, Venting Systems and Air Supply for
Appliances.
WARNING
Asphyxiation Hazard. Adequate combustion and
ventilation air must be provided to assure proper
combustion. Install combustion air intake per
Section IV “Venting”.
F. The boiler should be located so as to minimize
the length of the vent system. The combustion air
piping must terminate where outdoor air is available for
combustion and away from areas that may contaminate
combustion air. In particular, avoid areas near chemical
products containing chlorines, chlorouorocarbons,
paint removers, cleaning solvents and detergents.
Avoid areas containing saw dust, loose insulation bers,
dry wall dust etc.
NOTICE
Avoid operating this boiler in an environment
where sawdust, loose insulation bers, dry wall
dust, etc. are present. If boiler is operated under
these conditions, the burner interior and ports
must be cleaned and inspected daily to insure
proper operation.
G. General
1. Alpine boilers are intended for installations
in an area with a oor drain or in a suitable drain
pan to prevent any leaks or relief valve discharge to
cause property damage.

103448-07 - 1/16 11
2. Alpine boilers are not intended to support
external piping and venting. All external piping and
venting must be supported independently of the
boiler.
3. Alpine boilers must be installed level to
prevent condensate from backing up inside the
boiler.
4. Alpine boilers can be installed either as oor
standing (ALP080B through ALP285B) or as wall
hung (ALP080B through ALP210B). Factory
assembled oor standing models are identied with
sufx F in a boiler part number code (example _
ALP210BF-1L02). Factory assembled wall hung
models are identied with sufx W in a boiler part
number code (example - ALP210BW-1L02).
5. Boiler Floor Standing Installation:
a. For basement installation provide a solid base
such as concrete, where oor is not level or water
may be encountered on the oor around boiler.
Floor must be able to support weight of boiler,
water and all additional system components.
b. Boiler must be level to prevent condensate from
backing up inside the boiler.
c. Provide adequate space for condensate piping or
a condensate pump if required.
Boiler Clearances to Combustible (and Non-
Combustible) Material:
Models ALP080B through ALP210B and ALP285B:
These boilers are listed for closet installation with the
following minimum clearances – Top = 1 in. (25 mm),
Front = 1 in. (25 mm), Left Side = 10 in. (250 mm),
Right Side = 2 in. (50 mm), Rear = *6 in. (150 mm)
* Note:
When boiler is vented vertically, the minimum
clearance from the rear of the jacket is increased to
18 in. (460 mm) with a short radius 90° elbow in
order to provide adequate space at boiler rear for
installation of vent and air intake piping and service
access.
III. Pre-Installation and Boiler Mounting G. General (continued)
Listed Direct
Vent System
Vent Pipe
Material
Vent
Pipe
Direction
Enclosure
Vent Pipe
Nominal
Diameter
Minimum
Clearance to
Combustible
Material
Factory Standard
Two-Pipe CPVC/PVC Vent and PVC
Combustion Air Intake
* CPVC/PVC
Vertical or
Horizontal
Unenclosed
at all Sides
3 in. (80 mm)
or
4 in.( 100 mm)
1 in. (25 mm)
Available Optional
Two-Pipe Rigid Polypropylene Vent
(or, Flexible Polypropylene Liner
for Vertical Venting only) and Rigid
Polypropylene or PVC Combustion
Air Intake
Pipe Rigid
Polypropylene
Vent (or,
Flexible
Polypropylene
Liner for
Vertical
Venting only)
3 in. (80 mm)
or (110 mm)
or
4 in. (100 mm)
or (110 mm)
1 in. (25 mm)
Available Optional
Two-Pipe Stainless Steel Vent and
Galvanized Steel or PVC Combustion
Air Intake
Stainless
Steel
3 in. (80 mm)
or
4 in.( 100 mm)
1 in. (25 mm)
Figure 2A: Clearances To Combustible and Non-combustible Material, Floor Standing

12 103448-07- 1/16
Figure 2B: Clearances To Combustible and Non-combustible Material, Wall Mounted
III. Pre-Installation and Boiler Mounting G. General (continued)
Boiler Service Clearances – Applicable to all Boiler
Models:
Top = 24 in. (610 mm), Front = 24 in. (610 mm), Left
Side = 24 in. (610 mm), Right Side = 24 in. (610 mm),
Rear = 24 in. (610 mm)
The above clearances are recommended for service
access but may be reduced to the Combustible Material
Clearances provided:
a. The boiler front is accessible through a door.
b. Access is provided to the condensate trap located
on the left side of boiler.
c. Access is provided to thermal link located at the
boiler rear (ALP285B only).
6. Boiler Wall Hung Installation:
a. If the boiler is installed on a framed wall,
minimum acceptable framing is 2 x 4 studs on
16” centers. The boiler mounting 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 4’s anchored to the studs.
CAUTION
Alpine boiler approximate dry weights:
ALP080BW – 98 lbs; ALP105BW – 112 lbs;
ALP150BW – 136 lbs: ALP210BW – 150 lbs
Two people are required to safely lift these
boilers onto the installed wall mounting
bracket.
Make sure that wall mounting bracket is an-
chored 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 re-
quirements for supporting these boilers. Such
local requirements take precedence over the
requirements shown below.
b. Locate Wall Mounting Bracket Kit carton (P/N
102988-01) enclosed inside boiler carton. The
kit contains Wall Mounting Bracket, Bottom
Securing Bracket, (4) 5/16” x 2” long hex head
lag screws, (4) 5/16” at plated washers and (2)
#8 x ½” Phillips round head sheet metal screws.

103448-07 - 1/16 13
III. Pre-Installation and Boiler Mounting G. General (continued)
c. 5/16 in. x 2 in. lag screws and 5/16 in. plated
washers are intended for mounting the boiler
directly onto studs covered with ½ in. drywall.
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
construction practice and applicable local codes.
d. Make sure that the surface to which the boiler is
mounted is plumb.
e. Before mounting the boiler, make sure that wall
selected does not have any framing or other
construction that will interfere with the vent pipe
penetration.
TOP EDGE OF BOILER
'HOLE C'
'HOLE A'
'HOLE D'
LEFT SIDE OF BOILER
1.0" MIN. CLEARANCE TO COMBUSTIBLE
10.0" MIN. CLEARANCE TO COMBUSTIBLES
16
253
4
WALL MOUNTING BRACKET
CENTER LINE
BOTTOM SECURING
BRACKET CENTER LINE
2.0" MIN. CLEARANCE TO COMBUSTIBLE
'HOLE B'
3
16" DIA. PILOT HOLES
FOR 5
16" LAG SCREWS
(4 PLACES)
Figure 2C: Wall Mounting Hole Location / Layout
f. Once a suitable location has been selected for the
boiler, and any needed modications have been
made to the wall, use Figure 2C to locate and
layout holes “A” and “B”. These holes must be
positioned on mounting stud centers if the boiler
is installed on a framed wall. 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 in. lag screws are used, drill 3/16 in.
pilot holes.
g. An alternate way to locate/mark holes “A” and
“B” is to use template P/N 102986-01 enclosed
into Vent Part Carton [P/N 102981-01
(ALP080BW/105BW) or P/N 102981-02
(ALP150BW/210W)], which can be found inside
boiler carton.

14 103448-07- 1/16
III. Pre-Installation and Boiler Mounting G. General (continued)
Figure 2D: Bottom Mounting Bracket Installation / Boiler Wall Mounting
BOILER
WALL BRACKET
BOTTOM
SECURING
BRACKET
5
16" X 2" LAG
SCREW (4X)
5
16" X 2" FLAT
WASHER (4X)
2 X 4
WALL STUD
16" C/C
BOILER HANGING
BRACKET
BOILER
#8 X 1
2" SMS (2X)
1
2" SHEET
ROCK
BOILER HANGING
BRACKET
BOTTOM
SECURING
BRACKET
CAUTION
When positioning the template in the desired
location on the wall insure that the minimum
clearances to combustible material at adjacent
walls and ceiling are maintained. Consult
Figures 2A through 2C in this manual. Be sure
to allow space at the boiler left side for gas and
water connections, as well as for access to the
condensate trap and boiler controls for servicing.
m. See Section IV Venting; Paragraph B, 4 “Field
Installation of CPVC Vent Pipe - Wall Mounted
Boiler Builds” for instructions on attaching the
vent system to the boiler.
WARNING
Vent pipe must be inserted rmly into vent
connector and secured by tightening the metal
strap worm screw.
n. After the boiler has been piped, wired, connected
to vent and combustion air system piping and
combustion performance testing completed per
Section IX “System Start-up”, install Access
Panel/Gasket assembly and secure with provided
four #8 x ½ in. black oxide Phillips head sheet
metal screws. See Figure 2E “Access Panel and
Gasket Installation”.
CAUTION
The outer edges of the template represent
minimum side, top and bottom clearances to
combustible material. If the template needs to be
cut to t into a selected location, it would indicate
the minimum clearances to combustible material
are not met.
h. Attach the wall hanging bracket using the 5/16
in. x 2 in. lag screws and 5/16 in. plated washers,
or other suitable anchors as appropriate (Figure
2D). Make sure the bracket is level.
i. Attach Bottom Securing Bracket to boiler air box
with two #8 x ½ in. Phillips round head sheet
metal screws. Refer to Figure 2D for details.
j. Hang the boiler on the installed wall bracket as
shown in Figure 2D.
k. If not already done in Step (4) locate and drill
holes “C” and “D” using the ob-round slots in
the Bottom Securing Bracket. Secure the Bracket
to the wall using the 5/16 in. x 2 in. lag screws
and 5/16 in. plated washers, or other fasteners as
appropriate (Figure 2D).
l. Verify that the front of the boiler is plumb. If it
is not, install shims (installer provided) at holes
“C” and “D” between the Bottom Securing
Bracket and the wall to adjust.

103448-07 - 1/16 15
Figure 2E: Access Panel and Gasket Installation
III. Pre-Installation and Boiler Mounting G. General (continued)
WARNING
Access Panel must be installed while boiler is in
operation.
H. Boiler Stacking
1. For installations with unusually high space
heating and/or domestic hot water heating loads,
where employing two (2) Alpine boilers will offer
the benets of greater operational efciency, oor
space savings and boiler redundancy, the Alpine
boilers may be installed stacked one on the top of
the other. Refer to Table 3 “Alpine Boiler Model
Stacking Combinations” for details.
Table 3: Alpine Boiler Model Stacking
Combinations
Bottom
Boiler Model Top Boiler Model (2)
ALP080B (1) ALP080B
ALP105B (1) ALP080B or ALP105B
ALP150B (1) ALP080B through ALP150B
ALP210B (1) ALP080B through ALP210B
ALP285B ALP080B, ALP105B, ALP150B & ALP285B
Notes: (1) Floor-mounted builds only
(2) Floor-mounted or wall-mounted build where applicable
2. To eld assemble individual Alpine boilers
into a stackable conguration, use the steps
below:
a. Position the bottom boiler rst. Refer to Sections
II “Unpacking Boiler” and III “Pre-Installation
& Boiler Mounting” of the manual for details.
Always position higher input boiler model as
bottom boiler.
b. Each Alpine boiler is factory packaged with two
(2) Stacking Boiler Attachment Brackets (P/N
101679-01) and the bracket mounting hardware
[six (6) self-drilling hex washer head plated
#8 x ½” long screws, P/N 80860743]. Locate
and remove the brackets and the hardware.
The Stacking Boiler Attachments Bracket
has three 7/32” diameter holes punched in a
triangular pattern. See Figure 3 “Stacking Boiler
Attachment Bracket Placement”.
c. Alpine boiler left and right side panels have
a series of dimples at panel top and bottom.
These dimples are positioning dimples for
Stacking Boiler Attachment Bracket mounting
screws. Side panel bottom positioning dimples
are evenly spaced from boiler front and back,
while side panel top positioning dimples follow
specic pattern to compensate for Alpine boiler
model variable depth.
d. Position the upper boiler on the top of the bottom
boiler and align boiler front doors and sides ush
with each other.
• Place rst Stacking Boiler Attachment
Bracket onto the upper boiler left side panel,
at the panel lower left corner and align
bracket two upper holes with corresponding
side panel lower dimples.
• The remaining lower bracket hole must align
with a matching bottom boiler left side panel
top positioning dimple.
• Once bracket holes and side panel dimple
alignment is veried, attach the bracket to
top and bottom boiler left side panels with
the mounting screws.
e. Repeat above procedure to install second
Stacking Boiler Attachment Bracket and secure
the stacked boiler right side panels together at
the front right corner.
f. Install the third Stacking Boiler Attachment
Bracket to secure top and bottom boiler left side
panels at the rear left corner. Align the bracket
holes with corresponding positioning dimples in
the top boiler and bottom boiler left side panels,
then secure bracket with the screws.
g. Repeat above procedure to install the forth
Stacking Boiler Attachment Bracket to secure
stacked boiler right side panels at the rear right
corner.
3. When installing stackable boiler
combinations observe the following
guidelines:
a. Venting - Top and bottom boilers must have their
individual vent piping and vent terminals.

16 103448-07- 1/16
III. Pre-Installation and Boiler Mounting H. Boiler Stacking (continued)
Figure 3: Stacking Boiler Attachment
Bracket Placement
boiler ue gas condensate line construction and
condensate disposal. Terminating individual
boiler condensate lines into common pipe prior
to drain disposal is permissible, providing
common pipe has sufcient ow capacity
to handle combined condensate volume of
stackable combination.
b. Gas Piping - Follow instructions in Section
VII “Gas Piping” of the manual for sizing
and installation of an individual boiler. When
common gas piping is sized, insure it will have
adequate capacity for combined input (CFH
gas ow) of the selected stackable boiler
combination.
c. Water Piping and Trim - Follow instructions
in Section VI “Water Piping and Trim” of the
manual for system piping and boiler secondary
piping selection/sizing based on combined
heating capacity and/or gross output of
the selected stackable boiler combination.
Follow instructions of Section VI “Water
Piping and Trim” for each individual boiler trim
installation.
d. Electrical - Follow instructions in Section VIII
“Electrical” of the manual to wire individual
boilers.
WARNING
Asphyxiation Hazard. No common manifold
venting is permitted. Each boiler must have its
own individual vent and combustion air pipes
and terminals.
For side-wall venting individual model vent
terminals must terminate not closer than 12
inches horizontally and three (3) feet vertically
from each other in order to prevent combustion
air contamination. For vertical through the roof
venting, individual vertical vent terminals, if
level with each other, must be spaced no closer
than 12 inches horizontally. If vertical terminals
cannot end in one plane, they must be spaced no
closer than three (3) feet horizontally.
If vertical vent terminals cannot end in one
plane, they must be spaced no closer then three
(3) feet horizontally.
Follow instructions in Section IV “Venting”
of the manual for specics of individual boiler
vent termination. Follow instructions in Section
V “Condensate Disposal” for each individual

103448-07 - 1/16 17
IV. Venting
WARNING
Asphyxiation Hazard. Failure to vent this boiler in accordance with these instructions could cause
products of combustion to enter the building resulting in severe property damage, personal injury or
death.
Do not use a barometric damper, draft hood or vent damper with this boiler.
Do not locate vent termination under a deck.
Do not locate vent termination where exposed to prevailing winds.
Do not locate combustion air termination where chlorines, chlorouorocarbons (CFC’s), petroleum
distillates, detergents, volatile vapors or other chemicals are present. Severe boiler corrosion and
failure will result.
Use outdoor air for combustion. Do not obtain combustion air from within the building.
Use specied vent and combustion air pipe diameters. Do not reduce specied diameters of vent and
combustion air piping.
Do not interchange vent systems or materials unless otherwise specied.
Do not apply thermal insulation to vent pipe or ttings.
Moisture and ice may form on surface around vent termination. To prevent deterioration, surface must
be in good repair (sealed, painted, etc.).
Do not allow low spots in the vent where condensate may pool.
The CPVC vent materials supplied with this boiler do not comply with Natural Gas and Propane
Installation Code, CAN/CSA B149.1.S1-07 and are not approved for use in Canadian jurisdictions that
require vent systems be listed to ULC S636-2008. In these jurisdictions, vent this boiler using either
stainless steel Special Gas vent or a listed ULC S636 Class IIB venting system.
Figure 4: Location of Vent Terminal Relative to Windows, Doors, Grades, Overhangs, Meters and Forced Air
Inlets - Two-Pipe System Vent Terminal (Shown) Two-Pipe System Air Intake Terminal (Not Shown)

18 103448-07- 1/16
IV. Venting A. General Guidelines (continued)
A. General Guidelines
1. Listed Vent/Combustion Air Systems
a. Install vent system in accordance with National
Fuel Gas Code, ANSI Z223.1/NFPA 54 or
Natural Gas and Propane Installation Code,
CAN/CSA B149.1 Installation Code for Canada,
or, applicable provisions of local building codes.
Contact local building or re ofcials about
restrictions and installation inspection in your
area.
b. The Alpine is a Direct Vent (sealed combustion)
boiler. Combustion air must be supplied directly
to the burner enclosure from outdoors and ue
gases must be vented directly outdoors.
c. The following combustion air/vent system
options are listed for use with the Alpine boilers
(refer to Table 4):
i. Two-Pipe CPVC/PVC Vent/Combustion
Air System - Separate CPVC/PVC pipe
serves to expel products of combustion and
separate PVC pipe delivers fresh outdoor
combustion air. Refer to Part B for specic
details.
ii. Two-Pipe Polypropylene Vent/Combustion
Air System - Separate rigid or exible
polypropylene pipe serves to expel
products of combustion and separate rigid
polypropylene or PVC pipe delivers fresh
outdoor combustion air. Refer to Part C for
specic details.
iii. Two-Pipe Stainless Steel Vent/Combustion
Air System - Separate stainless steel pipe
serves to expel products of combustion
and separate PVC or galvanized steel pipe
delivers fresh outdoor combustion air. Refer
to Part D for specic details.
2. Vent/Combustion Air Piping
a. Do not exceed maximum vent/combustion air
lengths listed in Table 5A. Vent/combustion
air length restrictions are based on equivalent
length of vent/combustion air pipe (total length
of straight pipe plus equivalent length of
ttings). Table 6A lists equivalent lengths for
ttings. Do not include vent/combustion air
terminals in equivalent feet calculations. Use
vent/combustion air equivalent length worksheet
provided in Table 6B.
b. Maintain minimum clearance to combustible
materials. See Figure 2A or 2B for details.
c. Enclose vent passing through occupied or
unoccupied spaces above boiler with material
having a re resistance rating at least equal to the
rating of adjoining oor or ceiling.
Note: For one or two family dwellings, re
resistance rating requirement may not need
to be met, but is recommended.
d. Slope horizontal vent pipe minimum 1/4 in/ft
(21 mm/m) downward towards the boiler.
Les chaudières de catégories I, II et IV doivent
présenter des tronçons horizontaux dont la pente
montante est d’au moins 1/4 po par pied (21
mm/m) entre la chaudière et l’évent.
e. If possible, slope horizontal combustion air
pipe minimum 1/4 in/ft (21 mm/m) downward
towards terminal. If not, slope towards boiler.
f. Use noncombustible ¾ in. pipe strap to support
horizontal runs and maintain vent location and
slope while preventing sags in pipe. Do not
restrict thermal expansion or movement of vent
system. Maximum support spacing is 4 ft. (1.2
m). Avoid low spots where condensate may
pool. Do not penetrate any part of the vent
system with fasteners.
Les instructions d´installation du système
d´évacuation doivent préciser que les sections
horizontales doivent être supportées pour
prévenir le échissement. Les méthodes et les
intervalles de support doivent être spéciés.
Les instructions divent aussi indiquer les
renseignements suivants:les chaudières de
catégories II et IV doivent être installées de
façon à empêcher l´accumulation de condensat:
et si nécessaire, les chaudières de catégories
II et IV doivent être pourvues de dispositifs
d´évacuation du condensat.
g. For multiple boiler installations with vertical
roof terminals, separate vent pipes from multiple
boilers may be piped through a common conduit
or chase so that one roof penetration may be
made.
3. Vent/Combustion Air Terminals
Install venting system components on exterior
of building only as specically required by these
instructions (refer to Figure 4).
a. Use only listed vent/combustion air terminals.
i. Horizontal Sidewall Venting: For models
ALP080B thru ALP285B, use coupling for
vent terminal and 90° elbow for combustion
air intake terminal as shown in Figure 5).
Alternate staggered and snorkel terminations
are shown in Figure 6A and Figure 6B.
ii. Vertical Roof Venting: Use straight
coupling on vent and two 90° elbows turned
downwards for combustion air as shown in
Figure 7A. and Figure 8).

103448-07 - 1/16 19
IV. Venting A. General Guidelines (continued)
iii. For Alpine boilers factory build prior to
January 2016, US Boiler provided PVC tees
(3” or 4” as applicable to specic boiler
model) to be used either as vent or air intake
terminals.
For Alpine boilers factory build after
January 2016, US Boiler provides PVC
coupling (2”, 3” or 4” as applicable to
specic boiler model) to be used as vent
terminal and PVC 90° elbow (2”, 3” or 4”
as applicable to specic boiler model) to be
used as air intake terminal.
Both above listed combinations of vent/air
intake terminations are approved/permissible
to use per Intertek Alpine Listing Report No.
3132672CRT-04.
b. Maintain correct clearance and orientation
between vent and combustion air terminals.
i. Space center lines of vent and combustion
air terminals minimum 12 in. (300 mm)
apart. Spacing of more than 12 in. (300
mm) is recommended.
ii. If possible, locate vent and combustion
air terminals on the same wall to prevent
nuisance shutdowns. If not, boiler may
be installed with roof vent terminal and
sidewall combustion air terminal.
iii. When installed on the same wall, locate
vent terminal at same height or higher than
combustion air terminal.
iv. When using tee terminals, do not locate vent
terminal directly above air intake as dripping
condensate may freeze on and block intake.
c. Locate bottom of vent and combustion air
terminals at least 12 in. (300 mm) [18 in. (460
mm) in Canada] above the normal snow line and
at least 12 in. (300 mm) above grade level.
d. Locate vent and combustion air terminals at
least 12 in. (300 mm) from any door, window, or
gravity inlet into the building.
e. Do not install vent terminal directly above
windows or doors.
f. Locate bottom of vent terminal at least 3 ft. (900
mm) above any forced air inlet located within 10
ft. (3.0 m).
g. If window and/or air inlet is within 4 ft. (1.2 m)
of an inside corner, maintain at least 6 ft. (1.8 m)
spacing between terminal and adjoining wall of
inside corner.
h. Locate bottom of vent terminal at least 7 ft. (2.1
m) above a public walkway.
i. Maintain minimum clearance of at least 4 ft.
(1.2 m) [3 ft. (900 mm) in Canada] horizontally
between vent terminal and gas meters, electric
meters, regulators, and relief equipment. Do
not install vent terminal above or below this
equipment.
j. Do not locate the vent terminal under decks or
similar structures.
k. Top terminal must be at least 24 in. (609.6
mm) below ventilated eves, softs and other
overhangs. In no case may the overhang
exceed 48 in. (1219.2 mm). Where permitted
by the authority having jurisdiction and local
experience, the terminal may be located closer
to unventilated softs. The minimum vertical
separation depends upon the depth of the soft.
See Figure 4 for details.
l. Maintain minimum 12 in. (300 mm) horizontal
spacing between vent terminal and a building
corner.
m. Under certain conditions, water in the ue gas
may condense, and possibly freeze, on objects
around the terminal including on the structure
itself. If these objects are subject to damage by
ue gas condensate, they should be moved or
protected.
n. If possible, install the vent and combustion air
terminals on a wall away from the prevailing
wind. Reliable operation of this boiler cannot be
guaranteed if terminals are subjected to winds in
excess of 40 mph (64 km/hr).
o. Do not locate combustion air terminal in areas
that might contain combustion air contaminates,
such as near swimming pools.
p. For multiple boiler installations with horizontal
wall terminals, maintain minimum 12 in. (300
mm) horizontal distance between adjacent boiler
vent terminals. Maintaining greater spacing is
recommended to avoid frost damage to building
surfaces where vent terminations are placed.
q. For multiple boiler installations with vertical
roof terminals, maintain minimum 12 in. (300
mm) horizontal distance between adjacent boiler
vent terminals.

20 103448-07- 1/16
Table 4: Vent/Combustion Air Intake System Options
IV. Venting A. General Guidelines (continued)
Vent & Intake
Materials Option Penetration Through Structure Termination Figures Component Table
Reference
Section
Standard CPVC/PVC
Two-Pipe, CPVC/PVC
Vent and PVC Air Intake
1Intake Horizontal Sidewall 90° Elbow w/ Screen 5, 6A, 6B 7A, 7B
A.B
Vent Horizontal Sidewall Coupling w/ Screen
2Intake Horizontal Sidewall Ipex Low Prole 6D, 6E 7D
Vent Horizontal Sidewall
3Intake Horizontal Sidewall Ipex FGV Concentric 6G, 6H, 6J 7F
Vent Horizontal Sidewall
4Intake Horizontal Sidewall DiversiTech (HVENT) 6D, 6F 7E
Vent Horizontal Sidewall
5Intake Horizontal Sidewall DiversiTech (CVENT)
Concentric 6G, 6H, 6J 7G
Vent Horizontal Sidewall
6Intake Horizontal Sidewall 90° Elbow w/ Screen 6C 7A, 7B
Vent Vertical Roof Coupling w/ Screen
7Intake Vertical Roof (2) 90° Elbows w/ Screen 7A, 8 7C
Vent Vertical Roof Coupling w/ Screen
8Intake Vertical Roof Ipex FGV Concentric 7B, 6H 7F
Vent Vertical Roof
9Intake Vertical Roof DiversiTech (CVENT)
Concentric 7C, 6H 7G
Vent Vertical Roof
Optional Polypropylene
Two-pipe, Rigid PP
Vent or Flexible PP
Vent (Vertical Only) and
Rigid PP or PVC Air
Intake
10
Intake Horizontal Sidewall UV Resistant 90° Elbow
w/Screen 5, 6A, 6B
8, 9A, 9B,
9C, 9D A, C
Vent Horizontal Sidewall UV Resistant Straight Pipe
w/Screen
11
Intake Horizontal Sidewall UV Resistant 90° Elbow
w/Screen 6C
Vent Vertical Roof UV Resistant Straight Pipe
w/Screen
12
Intake Vertical Roof (2) UV Resistant 90° Elbows
w/Screen 7A, 8
Vent Vertical Roof UV Resistant Straight Pipe
w/Screen
13
Intake Horizontal Sidewall UV Resistant 90° Elbow
w/Screen
16A, 16B
Vent Vertical Roof
Polypropylene Flex Terminal
(B-vent Chase
used for vent only)
14 Intake Vertical Roof Polypropylene Flex Terminal (B-vent Chase used for vent
and air intake)
16D, 16E
Vent Vertical Roof
Optional Stainless Steel
Two-pipe, SS Vent and
Galvanized Steel or
PVC
Air Intake
15
Intake Horizontal Sidewall 90° Elbow w/Screen
5, 6A, 6B
10A, 10B A, D
Vent Horizontal Sidewall Straight Termination
w/Screen
16
Intake Horizontal Sidewall 90° Elbow w/Screen
6C
Vent Vertical Roof Straight Termination
w/Screen
17
Intake Vertical Roof (2) 90° Elbows w/Screen
7A, 8
Vent Vertical Roof Straight Termination
w/Screen