Crown Boiler TWB Series User manual

TWB Series
Oil-Fired Hot Water Boilers
INSTALLATION INSTRUCTIONS
These instructions must be axed on or adjacent to the boiler
Models:
• TWB065
• TWB075
• TWB100
• TWB125
• TWB150
• TWB175
• TWB200
DESIGNED TO LEAD
Equipped with Hydrolevel
3250-Plus Control System
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 fuel supplier. Read these instructions carefully before installing, operating, or
servicing this boiler. Keep boiler and any provided component instructions in legible condition and
posted near boiler for reference by owner and service technician.
980270B Rev 0, 11-20
Crown Boiler Company
P.O. Box 14818
3633 I Street
Philadelphia, PA 19134
www.crownboiler.com
9902339

1
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.
WARNING
This boiler is designed for use with #2 fuel oil meeting the specications of ASTM D-396. Attempts to burn
other liquid fuels, or to convert this boiler for use with gaseous fuels, could result in reliability problems,
extensive property damage, or loss of life.
NOTICE
This boiler has a limited warranty, a copy of which is included with this boiler.
The warranty for this boiler is valid only if the boiler has been installed, maintained and operated in
accordance with these instructions.
Surface rust on cast iron sections may be attributed to the manufacturing process as well as condensation
during storage. Surface rust is normal and does not a󰀨ect the performance or longevity of a boiler.
All boilers must be installed in accordance with National, State and Local Plumbing, Heating andAll boilers must be installed in accordance with National, State and Local Plumbing, Heating and
Electrical Codes and the regulations of the serving utilities. These Codes and Regulations may dier Electrical Codes and the regulations of the serving utilities. These Codes and Regulations may dier
from this instruction manual. Authorities having jurisdiction should be consulted before installationsfrom this instruction manual. Authorities having jurisdiction should be consulted before installations
are made.are made.
In all cases, reference should be made to the following Standards:In all cases, reference should be made to the following Standards:
USA BOILERSUSA BOILERS
A. Current Edition of American National StandardA. Current Edition of American National Standard ANSI/NFPA 31ANSI/NFPA 31, “, “Installation of OilInstallation of Oil
Burning EquipmentBurning Equipment”, for recommended installation practices.”, for recommended installation practices.
B. Current Edition of American National StandardB. Current Edition of American National Standard ANSI/NFPA 211ANSI/NFPA 211, “, “Chimneys, Fireplaces,Chimneys, Fireplaces,
Vents, and Solid Fuel Burning AppliancesVents, and Solid Fuel Burning Appliances”, For Venting requirements.”, For Venting requirements.
C. Current Edition of American Society of Mechanical EngineersC. Current Edition of American Society of Mechanical Engineers ASME CSD-1ASME CSD-1, “, “Controls andControls and
Safety Devices for Automatically Fired BoilersSafety Devices for Automatically Fired Boilers”, for assembly and operations of controls”, for assembly and operations of controls
and safety devices.and safety devices.
D. All wiring on boilers installed in the USA shall be made in accordance with the NationalD. All wiring on boilers installed in the USA shall be made in accordance with the National
Electrical Code and/or Local Regulations.Electrical Code and/or Local Regulations.
CANADIAN BOILERSCANADIAN BOILERS
A. Current Edition of Canadian Standards Association CSA B139, “A. Current Edition of Canadian Standards Association CSA B139, “Installation Code for OilInstallation Code for Oil
Burning EquipmentBurning Equipment", for recommended Installation Practices.", for recommended Installation Practices.
B. All wiring on boilers installed in Canada shall be made in accordance with the CanadianB. All wiring on boilers installed in Canada shall be made in accordance with the Canadian
Electrical Code and/or Local Regulations.Electrical Code and/or Local Regulations.
IMPORTANT INFORMATION - READ CAREFULLY

2
WARNING
Improper installation, adjustment, alteration, service or maintenance can cause property damage, personal
injury or loss of life. Failure to follow all instructions in the proper order can cause personal injury or death.
Read and understand all instructions, including all those contained in component manufacturers manuals
which are provided with the boiler before installing, starting-up, operating, maintaining or servicing this
boiler. Keep this manual and literature in legible condition and posted near boiler for reference by owner
and service technician.
This boiler requires regular maintenance and service to operate safely. Follow the instructions contained
in this manual.
Installation, maintenance, and service must be performed only by an experienced, skilled and knowledgeable
installer or service agency.
All heating systems should be designed by competent contractors and only persons knowledgeable in
the layout and installation of hydronic heating systems should attempt installation of any boiler.
Installation is not complete unless a pressure relief valve is installed as shown in Figure 8.1 located in
Section VIII, “System Piping” of this manual.
It is the responsibility of the installing contractor to see that all controls are correctly installed and are
operating properly when the installation is completed.
This boiler is not suitable for installation on combustible ooring. See Figure 5.1 for means of installing
boiler over a combustible oor. Do not install boiler on carpeting.
Do not tamper with or alter the boiler or controls.
Inspect ueways at least once a year - preferably at the start of the heating season. The inside of the
combustion chamber, the vent system and boiler ueways should be cleaned if soot or scale has accumulated.
When cleaning this boiler, take precaution to avoid damage to burner swing door insulation. If damaged,
or if there is evidence of previous damage, burner swing door insulation must be replaced immediately.
Oil Burner and Controls must be checked at least once a year or as may be necessitated.
Do not operate boiler with jumpered or absent controls or safety devices.
Do not operate boiler if any control, switch, component, or device has been subject to water.
Boiler construction materials, 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.
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.
DANGER
DO NOT store or use gasoline or other ammable vapors or liquids in the vicinity of this or any other appliance.

3
FOLLOW ALL INSTRUCTIONS and warnings printed
in this manual and posted on the boiler.
INSPECT THE BOILER, BURNER AND CONTROLS
ANNUALLY. To keep your boiler safe and e󰀩cient,
have a service technician follow the Service
checklist near the end of this 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.
Insu󰀩cient air may cause the boiler to produce
carbon monoxide or start a re.
KEEP FLAMMABLE LIQUIDS AWAY from the boiler,
including paint, solvents, and gasoline. The boiler
may ignite the vapors from the liquids causing
explosion or re.
KEEP CHILDREN AND PETS away from hot surfaces
of the boiler, boiler piping, and vent pipe.
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.
KEEP BOILER AREA CLEAN AND FREE OF FIRE
HAZARDS. All ammable debris, rags, paper, wood
scraps, etc., should be kept clear of the boiler at all
times.
WARNINGS FOR THE HOMEOWNER

4
READ THIS ENTIRE MANUAL before attempting
installation, start-up, or service. Improper
installation, adjustment, alteration, service, or
maintenance may cause serious property damage,
personal injury, or death.
DO NOT DISCONNECT PIPE FITTINGS on the boiler
or in the heating system without rst verifying that
the system is cool and free of pressure and that
your clothing will protect you from a release of hot
water or steam. Do not rely solely on the boiler’s
temperature and pressure gauge when making this
judgment.
USE PROPER PERSONAL PROTECTION
EQUIPMENT when servicing or working near the
boiler. Materials of construction, ue products, and
fuel contain alumina, silica, heavy metals, carbon
monoxide, nitrogen oxides, and/or other toxic or
harmful substances that can are hazardous to
health and life and that are known to the State of
California to cause cancer, birth defects, and other
reproductive harm.
INSTALL ALL GUARDS, cover plates, and
enclosures before operating the boiler.
SIZE THE BOILER PROPERLY relative to the design
heat load or, if using domestic hot water priority,
the peak hot water load, whichever is larger. A
grossly oversized boiler will cycle excessively and
this will lead to premature failure of the boiler and
its components. Our warranty does not apply to
damage from excessive cycling.
ADHERE TO ALL LOCAL CODE REQUIREMENTS.
Contact your local code inspector prior to
installation. In the absence of a local code, adhere to
the latest editions of the Installation of Oil Burning
Equipment ANSI/NFPA 31 in the USA or CAN/CSA
B139, Installation Code for Oil Burning Equipment in
Canada.
ALL WIRING must comply with the National
Electrical Code ANSI/NFPA 70 (in the USA) or the
Canadian Electrical Code CSA C22.1 (in Canada)
and any local regulations.
WARNINGS FOR THE INSTALLER
WARNING
This boiler must be properly vented. The chimney must be inspected for any obstructions and cleaned
prior to each heating season. A clean and unobstructed chimney ue is necessary to produce the minimum
draft required to safely evacuate noxious fumes that could cause personal injury or loss of life. Evidence
of loose debris and or condensate induced stains at the base of the chimney ue, connector or smokepipe
joints may be signs of condensing ue gases. Flue gas condensate is corrosive, which requires special
consideration and must be addressed immediately. Refer to Section VII, "Venting" in this manual for
more details.
This boiler needs fresh air for safe operation and must be installed so there are provisions for adequate
combustion and ventilation air.
This boiler is supplied with controls 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.
This boiler is designed to burn No. 2 fuel oil only. Do not use gasoline, crankcase drainings, or any oil
containing gasoline. Never burn garbage or paper in this boiler. Do not convert to any solid fuel (i.e.
wood, coal). Do not convert to any gaseous fuel (i.e. natural gas, LP).
All boilers equipped with burner swing door have a potential hazard which, if ignored, can cause severe
property damage, personal injury or loss of life. Before opening swing door, unplug burner power cord
from receptacle located in lower right corner of jacket front panel and turn o󰀨 service switch to boiler
to prevent accidental ring of burner outside the combustion chamber. Be sure to tighten swing door
fasteners completely when service is completed.

5
Table of Contents
I. Product Description ............................................................................... 6
II. Specications ......................................................................................... 6
III. Before Installing .................................................................................... 7
IV. Field Assembly ...................................................................................... 8
V. Locating the Boiler ................................................................................ 11
VI. Air for Combustion & Ventilation ......................................................... 12
VII. Venting ................................................................................................... 17
VIII. System Piping ........................................................................................ 19
IX. Tankless Heater Piping .......................................................................... 23
X. Fuel Line Piping .................................................................................... 24
XI. Wiring .................................................................................................... 27
XII. Start-Up & Checkout ............................................................................. 31
XIII. Operation ............................................................................................... 34
XIV. Service & Maintenance .......................................................................... 40
XV. Troubleshooting ..................................................................................... 43
XVI. Parts ....................................................................................................... 48

6
I Product Description
The TWB series boiler is a cast iron oil-red water boiler designed for use in closed forced circulation heating systems.
This boiler must be vented by natural draft into a lined masonry or metal chimney, or Type L vent. An adequate supply of
air for combustion, ventilation and dilution of ue gases must be available in the boiler room. An optional tankless heater is
available to generate domestic hot water.
II Specications
FIGURE 2.0: GENERAL CONFIGURATION *
(GAL/HR
)
(MBH) (MBH) (Gal)
5
5
TWB SPACE HEATING RATINGS
BASIC BOILER
MODEL
DOE
HEATING
CAPACITY
70
80
8
13 5/16 8
NUMBER
OF
SECTIONS
3
3
3
4
4
22-3/8 10 13/16 7
10 13/16 7
17-3/8 8 5/16 6
8 5/16 6
22-3/8
27-3/886.4
86.1 27-3/8
13 5/16
106
129
158
186
80
92
122
148
182
16.0
16.0
16.0
24.0
24.0
20.0
20.0
NET AHRI
RATING,
WATER
APPROX.
WATER
VOL. **
AFUE %
DIMENSIONS (in.)
8 5/16 6
"A"
87.3
87.0
86.3
87.0
17-3/8
17-3/8
TWB065
TWB075
TWB100
TWB125
TWB150 86.0
231
214
201
TWB175
TWB200
"B" "C"
0.65
0.75
1.00
1.20
1.50
1.75
1.90
BURNER
INPUT
TABLE 2.1: SPECIFICATIONS
Notes:
1. Net Ratings are based on piping and pick-up allowances of 1.15. The manufacturer should be consulted before selecting a boiler for installations
having unusual piping and pickup requirements.
2. Burner Capacity Rating, GPH is based on #2 oil with a Gross Heating Value equal to 140000 BTU/Gal.

7
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 latest
edition of Installation of Oil Burning Equipment (ANSI/NFPA31).
• Where required by the authority having jurisdiction, this installation must conform to the latest edition of Standard for
Controls and Safety Devices for Automatically Fired Boilers (ANSI/ASME CSD-1).
2) Make sure that a properly sized chimney is available which is in good condition. Consult the authority having
jurisdiction, Part VII of this manual, and ANSI/NFPA31 for additional information on venting requirements.
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 including a Crown Mega-Stor indirect water heater, size the boiler to have either the Heating
Capacity required for the Mega-Stor or the Net AHRI Rating required for the heating system, whichever results
in the larger boiler.
• For systems that incorporate other indirect water heaters, refer to the indirect water heater manufacturer’s
instructions for boiler output requirements.
4) In some cases, boilers installed at altitudes above 2000ft may require a dierent burner conguration from that at sea
level. Consult the local Crown representative for more information.
TABLE 2.2: OPTIONAL TANKLESS HEATER RATINGS
TWB065
TWB075
TWB100
TWB125
TWB150
TWB175
TWB200
4.00
Boiler Model
2.75
3.00
4.25
4.75
Rating
(GPM)
3.25
3.75
CAUTION
Fuel oil used with this boiler must conform to ASTM D396. The ASTM D396 standard sets a
5% limit on biodiesel concentration, requires that the biodiesel feedstock comply with ASTM
D6751, and also specifies the procedure that must be used to blend the biodiesel feedstock
with the #2 fuel oil. Attempts to use biodiesel blends not meeting all ASTM D396 requirements
may result in unreliable operation or severe property damage.
Tankless heater ratings based on 40F inlet water, 140F outlet water, and 190F
boiler water. Ratings are also based on 5 minute intermittent draws with 10
minutes between draws.

8
CAUTION
As with all oil-fired appliances, “Power Venting” this boiler creates a number of potential
problems, especially when this is done through a side wall. These include, but are not
necessarily limited to:
• Accelerated rate of soot buildup on the oil burner cad-cell, burner head, and/or in the
boiler itself.
• Odor complaints
• Severe damage to the side of the structure in the event that the boiler operates at a high
smoke level.
These problems can occur for many reasons, some of which are out of the control of both the
installer and the appliance manufacturer. The use of a chimney to vent this boiler is therefore
recommended. If a power venter must be used, it is the responsibility of the installer and power
venter manufacturer to “engineer” the power vent system. CROWN BOILER COMPANY WILL
ASSUME NO RESPONSIBILITY FOR DAMAGE TO SIDING, ETC. FROM A POWER VENTED OIL-
FIRED BOILER. THIS APPLIES REGARDLESS OF THE CAUSE OF THE SOOTING.
IV. Field Assembly
This boiler is shipped in two main pieces:
a. The crated boiler itself with the following loose parts packed in one or more cartons that are glued to the skid:
• Barometric Draft Regulator
• Circulator (if supplied)
• Relief valve
• Pipe Fittings
• Loose Flue Baes (TWB100 Only)
b. The burner carton consisting of the following items:
• Oil Burner assembly complete with cord and nozzle installed. This nozzle is for the highest ring
rate on which that burner can be used. See Table 4.0 below.
• An extra nozzle, and in some cases a low ring rate bae, is shipped loose in the burner carton to allow the
burner to be down-red to the next smaller model. See Table 4.0 for details.
It is recommended that the boiler be moved to its nal location before the items in the burner carton are installed. To
complete eld assembly:
1) Make sure that the burner carton supplied is the correct one for the boiler. The crate tag on the boiler, and the boiler’s
rating plate, list the Crown part numbers for the burner cartons that may be used with the boiler.
2) Remove the burner mounting bolts and washers from the front door. Make sure that the burner gasket is in place and
undamaged. Mount the burner to the door.
WARNING
Installation of burners other than those provided by Crown, and marked for use with this boiler, may result in
unreliable operation, property damage, personal injury, or loss of life.
NOTICE
In addition to the boiler and burner cartons described above, this boiler also requires a Riello AL1008 24V
Switching Relay (Crown PN130080) when it is installed with the 131521R or 131522R burner boxes.

9
3) Plug the burner cord into the connector located inside the junction box on the front of the boiler. Secure the cover plate that
is on the burner cord to the junction box. This plate has keyhole slots that allow it to be mounted/unmounted for servicing
without removing the junction box screws.
4) Congure the boiler and burner for the desired ring rate using Table 4.0:
• If the burner will not be used at the higher ring rate, install the loose nozzle supplied. Note that the TWB075
also requires the installation of a low ring rate bae (LFRB) in the Beckett burner. Follow the Beckett instructions
supplied with the LFRB to install it. The TWB065 requires a nozzle which is not supplied; Procure the nozzle shown
in Table 4.0 locally.
• If the TWB100 is to be used as received (i.e. not converted to a TWB065 or TWB075), and if the boiler is installed
in the USA or Canada, the ue baes supplied loose must be installed in the boiler to meet the Federal minimum
eciency standard. DO NOT INSTALL THESE BAFFLES IF BOILER IS DOWNFIRED TO A TWB065 or
TWB075. To install these baes:
a. Remove the top jacket panels
b. Remove the ue collector
c. Drop one bae into each passage as shown in Figure 4.1
d. Replace ue collector and top jacket panels.
• If boiler is converted to a dierent ring rate complete the conversion label provided in the instruction manual
envelope and apply it next to the rating plate.
TABLE 4.0: FIELD ASSEMBLY COMPONENTS
BURNER1BOILER MODEL TWB0652TWB075 TWB100 TWB125 TWB150 TWB175 TWB200
BECKETT
CROWN CARTON PART # 131521B 131522B 131523B
BASIC BURNER SPEC. AFG/70MMAQ AFG/70MDAQ AFG/70MLAQ
NOZZLE INSTALLED FOR TWB100 TWB150 TWB200
LOOSE NOZZLE SUPPLIED
FOR3TWB075 TWB125 TWB175
CARLIN
CROWN CARTON PART # 131521C 131522C NEW “C3”
BASIC BURNER SPEC. EZ-1HP EZ-1HP EZ-1HP
NOZZLE INSTALLED FOR TWB100 TWB150 TWB175
LOOSE NOZZLE SUPPLIED
FOR TWB075 TWB125 N/A
RIELLO
CROWN CARTON PART # 131521R 131522R NEW “R4”
BASIC BURNER SPEC. 40F5 40F5 40F10
NOZZLE INSTALLED FOR TWB100 TWB150 TWB200
LOOSE NOZZLE SUPPLIED
FOR TWB075 TWB125 TWB175
QUANTITY OF FLUE BAFFLES 0 0 243545
Notes:
1. Consult Table 12.0a-c for complete burner and nozzle specications.
2. No nozzle is supplied for the TWB065. Consult Table 12.0a-c for the appropriate TWB065 nozzle spec and procure locally.
There is no TWB065 application for the Riello burner.
3. Carton # 131521B also includes a low ring rate bae for use if burner is converted to a TWB075 or TWB065.
4. Flue baes are shipped loose on the TWB100. Install only if boiler will be red at 1.00 GPH AND boiler is installed in the
USA or Canada. Do not install ue baes if boiler is converted to a TWB075 or TWB065.
5. Flue baes are factory installed on TWB125 – TWB200.
WARNING
Installation of ue ba󰀪es in TWB075 or TWB065 could cause excessive ue gas condensation resulting in
property damage, personal injury, or loss of life.

10
FIGURE 4.1: FIELD INSTALLATION OF FLUE BAFFLES

11
V Locating the Boiler
1) Clearances:
• Observe the minimum clearances shown below. Except as noted, these clearances apply to all combustible con-
struction, as well as noncombustible walls, ceilings and doors. Also see Figure 5.0.
Front – 24”
Left Side – 6”
Right Side – 6”
Rear – 6”
Top – 6”
Single Wall Chimney Connector (to combustible construction) - 18”
• A 24” service clearance from the jacket is recommended from the top of the boiler. This clearance may be
reduced to that shown above; however, servicing the boiler will become increasingly dicult as this clearance is
reduced.
2) If listed Type L vent is used, follow vent pipe manufacturer recommendations for minimum clearances.
3) Do not install this boiler directly on a combustible surface. Where it is desired to install this boiler over a non-carpeted
combustible surface, install the boiler on the base shown in Figure 5.1.
4) Do not install this boiler in a location where gasoline, ammable vapors, or other ammable materials will be stored or
used.
5) Do not install this boiler in an area where large amounts of airborne dust will be present, such as a workshop.
WARNING
Failure to observe the following location requirements could result in property damage, a fire,
explosion or carbon monoxide (CO) hazard.
FIGURE 5.0: CLEARANCES
`

12
VI Air for Combustion and Ventilation
Sucient fresh air must be supplied for combustion and ventilation. Provisions for combustion and ventilation air for oil
burning equipment must be made in accordance with Section 1.5, Air for Combustion and Ventilation, in the latest edition of
Installation of Oil Burning Equipment (ANSI/NFPA 31).
To ensure an adequate supply of air for combustion, ventilation and ue gas dilution, start by determining whether the
boiler is to be installed in a building of unusually tight construction. A building of unusually tight construction can be dened
as one having the following features:
• Walls and ceilings exposed to outside atmosphere have a continuous water vapor retarder with a rating of 1 perm or
less with openings gasketed and sealed
• Weather stripping has been added on openable windows and doors
• Caulking and sealants are applied to areas such as joints around window and door frames, between sole plates and
oors, between wall-ceiling joints, between wall panels, at penetrations for plumbing, electrical, and gas lines, and
at other openings.
WARNING
• Insufficient combustion air supply may result in the production and release of soot or
deadly carbon monoxide (CO) into the home which can cause property damage, severe
personal injury or death.
• This boiler is not designed for use in a space that is depressurized relative to the outdoors.
Operating this boiler in a depressurized space may cause property damage, severe
personal injury or death.
FIGURE 5.1: INSTALLATION OVER A COMBUSTIBLE FLOOR

13
For Buildings of Other than Unusually Tight Construction
1) Determine whether the boiler is to be installed in a conned space - A conned space is dened as having a volume less
than 50 cubic feet per 1000 BTU/hr input of all appliances installed in that space. To determine whether the boiler room is a
conned space:
a. Total the input of all appliances in the boiler room in thousands of BTU/hr. Round the result to the next highest
1000 BTU/hr.
b. Find the volume of the room in cubic feet. The volume of the room in cubic feet is:
Length (ft) x width (ft) x ceiling height (ft)
In calculating the volume of the boiler room, consider the volume of adjoining spaces only if no doors are installed
between them. If doors are installed between the boiler room and an adjoining space, do not consider the volume of
the adjoining space, even if the door is normally left open.
c. Divide the volume of the boiler room by the input in thousands of BTU/hr. If the result is less than 50, the boiler
room is a conned space.
Example:
A TWB100 and a water heater are to be installed in a room measuring 6 ft - 3 in x 7 ft with an 8 ft ceiling. The
water heater has an input of 30000 BTU/hr:
Input of TWB100 = 1.00 Gal/hr x 140000 BTU/Gal = 140000 BTU/hr
Total input in thousands of BTU/hr = (140000 BTU/hr + 30000 BTU/hr)/1000 = 170
Volume of room = 6.25 ft x 7 ft x 8 ft = 350 ft3
350/170 = 2.06. Since 2.06 is less than 50, the boiler room is a conned space.
FIGURE 6.0: BOILER INSTALLED IN CONFINED SPACE, ALL AIR FROM INSIDE

14
2) Unconned Space - Natural inltration into the boiler room will normally provide adequate air for combustion and venti-
lation without additional louvers or openings into boiler room.
3) Conned Space - Provide two openings into the boiler 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 must be within 12” of the oor
(Figure 5.0).
• Each opening must have a free area of 1 square inch per 1000 BTU/hr input of all fuel burning appliances in the boiler
room. The minimum opening dimension is 3 inches. Minimum opening free area is 100 square inches per opening.
• If the total volume of both the boiler room and the room to which the openings connect is less than 50 cubic feet per
1000 BTU/hr of total appliance input, install a pair of identical openings into a third room. Connect additional rooms
with openings until the total volume of all rooms is at least 50 cubic feet per 1000 BTU/hr of input.
• The “free area” of an opening takes into account the blocking eect of mesh, grills, and louvers. Where screens are
used, they must be no ner than ¼” (4 x 4) mesh.
For Buildings of Unusually Tight Construction:
1) Openings must be installed between the boiler room and the outdoors or a ventilated space, such as an attic or crawl
space, which communicates directly with the outdoors.
2) Two openings are required. The top edge of the upper opening must be within 12 inches of the ceiling. The bottom edge
of the lower opening must be within 12 inches of the oor.
3) Size openings and ducts as follows:
• Vertical ducts or openings directly outdoors (Figure 6.1, Figure 6.2, and Figure 6.3) - Each opening must have a free
cross sectional area of 1 square inch per 4000 BTU/hr of the total input of all fuel red appliances in the boiler room
but not less than 100 square inches. Minimum opening size is 3 inches.
• Openings to outdoors via horizontal ducts (Figure 6.4) - Each opening must have a free cross sectional area of 1 square
inch per 2000 BTU/hr of the total input of all fuel red appliances in the boiler room but not less than 100 square
inches. Minimum opening size is 3 inches.
• The “free area” of an opening takes into account the blocking eect of mesh, grills, and louvers. Where screens are
used, they must be no ner than ¼” (4 x 4) mesh.
FIGURE 6.1: ALL AIR FROM OUTDOORS, VENTILATED CRAWL SPACE AND ATTIC

15
FIGURE 6.2: ALL AIR FROM OUTDOORS, VIA VENTILATED ATTIC
FIGURE 6.3: ALL AIR FROM OUTDOORS, USING OPENINGS INTO BOILER ROOM

16
FIGURE 6.4: ALL AIR FROM OUTDOORS, USING HORIZONTAL DUCTS INTO BOILER ROOM

17
VII Venting
Vent installation must be in accordance with local building codes, or the local authority having jurisdiction.
Typical vent installation is illustrated by Figure 7.0. The components of vent installation are the vent connector (breeching),
barometric draft regulator, and chimney.
1) Acceptable Chimneys - The following chimneys may be used to vent this boiler:
• Listed Type L vent - Install in accordance with the manufacturer’s instructions, the terms of its listing, and applicable
codes.
• Masonry Chimney - The masonry chimney must be constructed in accordance with the latest edition of Standard
for Chimneys, Fireplaces, Vents, and Solid Fuel Burning Appliances (NFPA 211) and lined with a clay liner or other
listed lining system. Do not vent this boiler into an unlined chimney.
FIGURE 7.0: TYPICAL VENT SYSTEM INSTALLATION AND COMPONENTS
WARNING
• Improper venting may result in property damage and/or the release of flue gases, which
contain deadly carbon monoxide (CO), into the home, resulting in severe personal injury or
death.
• Inspect existing chimney before installing boiler. Failure to clean or replace damaged pipe
or tile lining will cause property damage, severe personal injury or death.

18
2) Acceptable Vent Connectors - The following may be used for vent connectors:
• Listed Type L vent.
• Single Wall Galvanized Pipe - Use 0.018” (26 gauge) or heavier.
3) Chimney and Vent Connector Sizing - See Table 7.1 for minimum vent connector and chimney sizing.
4) Do not vent this appliance into any portion of a mechanical vent system operating under positive pressure.
5) Do not connect the boiler into a chimney ue serving an open replace or other solid fuel appliance.
6) Prior to boiler installation, inspect chimney for obstructions or other defects and correct as required. Clean chimney as
necessary.
7) Vent pipe should slope upward from boiler not less than one inch in four feet. No portion of vent pipe should run
downward or have sags. Vent pipe must be securely supported.
8) The vertical section of vent pipe coming o the boiler should be as tall as possible, while still maintaining the proper
clearance from the horizontal vent connector to combustibles and the proper pitch called for in (7) above.
9) Vent pipe should be installed above the bottom of the chimney to prevent blockage.
10) Vent pipe must be inserted ush with inside face of the chimney liner and the space between vent pipe and chimney
sealed tight. A thimble permanently cemented in place can be used to facilitate removal of chimney connector for cleaning.
11) Install the barometric draft regulator in accordance with the regulator manufacturer’s instructions.
12) Secure all joints in the vent connector system with sheet metal screws. This includes the joint between the vent
connector and the boiler collar, as well as the barometric draft regulator. Use at least three screws at each joint.
TABLE 7.1: MINIMUM RECOMMENDED BREECHING AND CHIMNEY SIZE
Round I.D. (in) Rectangular I.D. (in) Height (ft)
TWB065 6 6 8 x 8 15
TWB075 6 6 8 x 8 15
TWB100 6 6 8 x 8 15
TWB125 7 7 8 x 8 15
TWB150 7 7 8 x 8 15
TWB175 8 8 8 x 8 15
TWB200 8 8 8 x 8 15
Boiler
Model
Min Breeching
Dia. (inches)
Min. Recommended Chimney Size and Height