Weil-McLain CGs User Manual

GOLD CGs

Gas-Fired Water Boiler

Venting Supplement

Vertical Direct Venting

For use with Weil-McLain

Roof or Through-Unused-Chimney
Termination Kit

Through-

87300

This Venting Supplement must only be used by a qualified installer/service
technician. Read these instructions completely before beginning the
installation. Failure to follow all instructions in proper order can cause
severe personal injury, death or substantial property damage.

To install a new vent system follow instructions in:

• This Venting Supplement.

• CGs Boiler Manual.

• Vent pipe manufacturer’s instructions supplied with vent material.

Part Number 550-141-873/0502

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Table of contents

1. Please — read before proceeding.................................3

Hazard definitions .................................................................................... 3

Venting method definitions ..................................................................... 3

To the installer.......................................................................................... 3

2. Determine venting method ..........................................4

Direct exhaust vent methods .................................................................. 4

Direct vent methods................................................................................. 5

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3. Combustion air supply — eliminate contamination .....6

4. Obtain vent system components .................................7

5. Install vent starter .....................................................10

6. Vertical direct vent — vent termination .................... 11

7. Installation guidelines ............................................... 11

8. Verify vent system length..........................................12

9. Installation — assembly .............................................14

2

Part Number 550-141-873/0502

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V

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enting — Venting — V

enting — V

enting — Venting — V

enting Supplemententing Supplement

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1. Please — read before proceeding . . . . .

Hazard definitions

Venting method

definitions

The following terms are used throughout this Venting Supplement to bring
attention to the presence of hazards of various risk levels or to important
information concerning the life of the product.

Indicates presence of hazards that will cause severe
personal injury, death or substantial property damage.

Indicates presence of hazards that can cause severe
personal injury, death or substantial property damage.

Indicates presence of hazards that will or can cause
minor personal injury or property damage.

Indicates special instructions on installation, operation
or maintenance that are important but not related to
personal injury or property damage.

Direct vent — Uses outside combustion air with combustion air connector

piping sealed at all joints and seams. Also known as sealed combustion.
All CGs flue gas vents are pressurized, requiring careful sealing of all joints.
See also

Exhaust: Vertical and Sidewall

Direct exhaust venting — Uses inside combustion air with no combustion

air connector piping. All CGs flue gas vents are pressurized, requiring careful
sealing of all joints. Also known as non-direct venting. See

Supplement — Direct Vent: Sidewall & Direct Exhaust: Vertical and
Sidewall

CGs Venting Supplement — Direct Vent: Sidewall & Direct

for alternate direct vent method.

CGs Venting

venting supplement for application information.

To the installer

Chimney draft vent — Uses the natural draft provided by a vertical vent

or chimney. (This method cannot be used with CGs boilers.)

Chimney draft venting cannot be used for CGs
boilers.

venting materials listed in this Venting Supplement.
Existing vertical vents or chimneys may only be used as
raceways for routing vent or vent/air piping as described
in this supplement or CGs Direct Vent Supplements.

Boiler must be vented and supplied with combustion
air as described in this supplement. Failure to do so will
result in severe personal injury, death or substantial
property damage.

Use only the sealant specified by the vent pipe
manufacturer, applied per their instructions. Vent
piping must be sealed gas-tight to prevent possibility
of flue gas spillage and carbon monoxide emissions,
resulting in severe personal injury or death.

Provide combustion and ventilation air openings as
described in the CGs Boiler Manual and this
supplement. Failure to provide adequate air supply
could result in severe personal injury, death or
substantial property damage.

Vent system must be constructed only using

Part Number 550-141-873/0502

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2. Determine venting method

To prevent potential of severe personal injury or death,
check for areas and products listed on page 6 before
installing boiler. If found:

• remove products permanently

—

OR —

• provide outside combustion air (direct vent

installation).

Figure 1 Typical sidewall direct exhaust

vent installation

Direct exhaust ventingDirect exhaust venting

Direct exhaust venting

Direct exhaust ventingDirect exhaust venting

Use only when openings for inside combustion air can
be supplied in accordance with the CGs Boiler manual,
this venting supplement and with all applicable codes.

You must direct vent the boiler if the boiler area may
contain contaminants as described in this supplement

Two direct exhaust vent options are permitted: sidewall
and vertical, per instructions in

Sidewall

Venting Supplement.

Figure 2 Typical vertical direct exhaust

& Direct Exhaust Venting: Vertical or Sidewall

vent installation

CGs Direct Venting:

.

87250

1. Sidewall direct exhaust venting

— using vent manufacturer’s termination fittings
listed in this supplement. See Figure 1.

See instructions on pages 6, 7, 8, 9 and 10 – 13.

4

2. Vertical direct exhaust venting

— using penetration through roof or using existing
unused chimney or vent as raceway for vent pipe.
See Figure 2.

See instructions in

Direct Exhaust: Vertical or Sidewall

Supplement.

CGs Direct Vent: Sidewall &

Part Number 550-141-873/0502

Venting

VV

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V

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VV

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Direct vent methodsDirect vent methods

Direct vent methods

Direct vent methodsDirect vent methods

Combustion air is provided by air piping connecting
from the boiler Air intake fitting to the outside.

You must direct vent the boiler (pipe outside air to
boiler air intake fitting) if the boiler area may contain
contaminants as described in this supplement.

Two direct vent options are permitted:

enting — Venting — V

enting — V

enting — Venting — V

1. Sidewall direct vent

enting Supplemententing Supplement

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Figure 4 Typical vertical direct vent

installation

— using Weil-McLain

Kit

. See instructions in

& Direct Exhaust: Vertical or Sidewall

Supplement. Termination kit is included with CGs
boiler. See Figure 3.

Vent/Air Intake Termination

CGs Direct Vent: Sidewall

2. Vertical direct vent

— using Weil-McLain

Unused-ChimneyTermination Kit

vertical direct venting are covered in this
supplement. See Figure 4.

Figure 3 Typical sidewall direct vent

installation

Through-Roof or Through-

. Instructions for

Venting

Part Number 550-141-873/0502

87203

87205

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3. Combustion air supply —
eliminate contamination

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If the boiler is installed in any area likely to cause

contamination

contaminate the air cannot be removed, you must pipe

combustion air to the boiler air intake

combustion air will damage the boiler, resulting in
possible severe personal injury, death or substantial
property damage. Do not install a CGs boiler in a

laundry room or pool facility

using ducted outside air. These areas will always contain
contaminants.

Please review the following information on potential
combustion air contamination problems.

Refer to Table 1 for products and areas that may cause
contaminated combustion air. These contaminants may
cause damage to the vent piping, and must be eliminated

Table 1 Corrosive contaminants

Products to avoid Areas likely to have contaminants

Spray cans containing chloro/fluorocarbons Dry cleaning/laundry areas and establishments

, or if products which would

. Contaminated

, for example, without

from the boiler combustion air supply. You may do this
by removing the contaminants permanently from the
area or piping air directly to the boiler (direct vent) using
one of the methods referenced in this supplement and
described in the direct vent supplements.

To prevent potential of severe
personal injury or death, check for
areas and products listed below
before installing boiler. If found:

• remove products permanently

— OR —

• provide outside combustion air

(direct vent installation).

Permanent wave solutions Swimming pools

Chlorinated waxes/cleaners Metal fabrication plants

Chlorine-based swimming pool chemicals Beauty shops

Calcium chloride used for thawing Refrigeration repair shops

Sodium chloride used for water softening Photo processing plants

Refrigerant leaks Auto body shops

Paint or varnish removers Plastic manufacturing plants

Hydrochloric acid/muriatic acid Furniture refinishing areas and establishments

Cements and glues New building construction

Antistatic fabric softeners used in clothes
dryers

Chlorine-type bleaches, detergents, and clean­ing solvents found in household laundry rooms

Adhesives used to fasten building products and
other similar products

6

Remodeling areas

Garages with workshops

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V

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4. Obtain vent system components

The following special gas vent systems comply with UL-1738 and ULC­S636 standards and are certified by CSA as the only systems suitable for
use with CGs boilers:

• Heat-Fab, Inc. Saf-T Vent

• Flex-L International, Inc. StaR-34

• Z-Flex®, Inc. Z-Vent II

•ProTech Systems FasNSeal™

Use only the vent starter of the same manufacturer as the vent compo­nents. Do not mix components from different systems. The vent system
could fail, causing flue gas spillage, resulting in severe personal injury or
death.

®

1. The

2. Verify that the vent termination will comply with the requirements

3. You will need to obtain stainless vent pipe and fittings, using only the

4. Use suitable 3" material for combustion air connector piping, such as:

Through-Roof or Through-Unused-Chimney Termination Kit

provides special parts required to route 3-inch stainless vent pipe
through 5-inch B-vent. The space between the vents provides the
passage for combustion air. See page 9 for parts included with the kit.

listed on page 11. Then verify that the vent and air piping will not
exceed the length limits given in section 8 of this supplement before
locating boiler or floor/roof penetrations.

vent systems listed in the CGi, CGs & GV Vent Component

Supplement. Also obtain B-vent pipe and fittings for the vertical run

and floor/roof penetrations (See Table 3).

• Dryer vent

• Galvanized steel

• PVC (3" I.D.)

Part Number 550-141-873/0502

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4. Obtain vent system components (continued)

Figure 5 Typical installation,

showing component
identification

Termination coupling

Elastomer
flashing*

5”Type “B”
storm ring

5”Type “B”
adjustable
flashing

Vent pipe

5”Type “B” rain cap with
hole in top for vent pipe

For minimum height
followType “B” gas
vent manufacturer’s
instruction

5”Type “B” stack

Fire stop

Fire stop

Single wall stack
reducer tee*

Cap with hole
for vent pipe

Elastomer
flashing*

3” vent pipe:

Heat-Fab Saf-T Vent

®

Z-Flex Z-Vent II
Flex-L International StaR-34
ProTech Systems FasNSeal™

* furnished in kit

®

Condensate drain line

Vent starter must be
by same manufacturer
as the vent pipe.

5” type “B” support

5” type “B” draft hood connector

Air intake pipe – 3” pvc,
standard 3” galvanized
or aluminum single
wall pipe, or 3” flexible
dryer vent

CGs boiler

87303

8

Part Number 550-141-873/0502

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Figure 6 Parts provided in kit Table 2 Parts provided in kit

enting — Venting — V

enting — V

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Item Description Qty

1 Tee —

galvanized 5" x 5" x 3"

2 Vent clamp 5

3 Bottom cap —

3

1

2

4

6

8

Table 3 Parts below are required for installation and are provided by installer (not included in kit)

7

5

87302

galvanized with 4 ½" hole

4 Vent support 1

5 Elastomer grippers 11

6 Screws — sheet metal

type A, #10 x 1¼"

7 Screws — sheet metal

type A, #10 x ½"

8 Elastomer flashing 2

1

1

11

3

Description Quantity

Rain cap, galvanized, 5" 1
Adjustable flashing, type B, 5" 1
Fire stop for each floor or attic penetration 1
Storm ring, type B, 5" 1
Support, type B, 5" 1
Draft hood connector, type B, 5" 1
Adequate B-Vent with clamp rings for combustion air run (less than 30 feet) -­Adequate 3" vent material for vent run and elbows from one of the following (See Note):

• Heat-Fab, Inc. — Saf-T Vent

• Flex-L International, Inc. — StaR-34 • Z-Flex
Adequate sealant specified by vent pipe manufacturer’s instructions -­Adequate 3" PVC, galvanized or dryer vent (for combustion air supply piping between tee and boiler) --
Note: Do not mix types of vent material. CSA certification will be void.

Part Number 550-141-873/0502

®

• ProTech Systems — FasNSeal™

®

, Inc. — Z-Vent II

--

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5. Install vent starter

1. Select a vent pipe manufacturer and obtain all vent
components needed, based on boiler location and
venting method.

2. You must use the vent starter made by the vent pipe
manufacturer. See separate CGi, CGs & GV Vent

Component Supplement

, for part numbers of each

component, listed by vent manufacturer.

Use only the vent starter of the same
manufacturer as the vent compo­nents. Do not mix components from
different systems. The vent system
could fail, causing flue gas spillage,
resulting in severe personal injury or
death.

Band clamp

Band clamp
strap

screw

FasNSeal™
starter

Band clamp
screw

Figure 7

FasNSeal™ vent starter

3. Follow all applicable national, state, local or
provincial codes when venting the CGs boiler.

4. Connect vent starter to blower housing outlet as
shown in the

Figures 7 through 10, below.

a. Do not mix components from different vent

manufacturers.

b. Maintain minimum 2" clearance from

combustible materials to vent pipe.

c. Seal with sealant specified by vent pipe

manufacturer, using ³⁄₈" bead (not required for
FasNSeal™).

d. Tighten strap at band clamp screw until strap is

snug around blower housing.

Tighten
position

Feed

Band clamp
strap

position

Z-Vent II
starter

Band clamp
screw

³⁄₈ " Bead
of sealant

Band clamp
strap

Blower
housing
outlet

87211

Saf-T Vent
starter

Band clamp
screw

³⁄₈ " Bead of
sealant

Blower
housing
outlet

87208

Z-Vent II vent starter

®

Figure 9

Saf-T Vent® vent starter

StaR-34 vent starter

Figure 8

Figure 10

Band clamp
strap

Blower
housing
outlet

87210

StaR-34
starter

Band clamp
screw

3/8" Bead
of sealant

Blower
housing
outlet

87209

10

Part Number 550-141-873/0502

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enting — Venting — V

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6. Vertical direct vent — vent termination

Follow instructions on this page
when determining vent location to
avoid possibility of severe personal
injury, death or substantial property
damage.

1. Locate the boiler and vent penetration through the
roof so all requirements on this page will be met.
Also follow vent manufacturer’s instructions.

2. Gases will form white plume in winter. Plume could
obstruct window view of nearby windows in multi­story buildings.

3. Prevailing winds could cause freezing of condensate
and water/ice buildup on vent termination, building,
plants or roof. Ice buildup on vent termination can
cause boiler shutdown and building freezeup.

4. Locate or guard vent termination to prevent
condensate from damaging exterior surfaces.

5. Locate the vent termination well away from trees,
shrubs, and decorative items.

6. Locate or guard vent to prevent accidental contact
by people or pets.

7. Do not terminate vent in window well, stairwell,
alcove, courtyard, or other recessed areas.

8. Do not wrap or insulate vent pipe or fittings.

9. Do not connect:

• Any other appliance to vent pipe.

• Multiple boilers to a common vent pipe.

10. Canadian installations — See B149.1 or B149.2
Installation Code. Terminate vent no less than 6 feet
from another combustion air inlet, 3 feet from any
other building opening, and 3 feet from any gas
service regulator.

11. The vent must terminate:

• more than 1 foot below or to side of all doors
or windows.

• more than 1 foot above grade or anticipated
snow line.

• 3 feet above any forced air intake within 10
feet.

12. Vent must also terminate:

• at least 6 feet away from adjacent walls.

• no closer than 5 feet below roof overhang.

• at least 4 feet horizontally (and in no case above
or below unless a 4 foot horizontal distance is
maintained) from electric meters, gas meters,
regulators, relief valves, and other equipment.

13. Site conditions may dictate greater clearances.
Do not terminate the vent adjacent

to a wall or below any building
extension such as eaves, parapets,
balconies or decks. Failure to
comply could result in severe
personal injury, death or substantial
property damage.

14. Multiple boilers may be vented with vent

terminations at the same height. Space
terminations to provide a minimum of 1 foot
between pipes for U.S. installations. For Canadian
installations, provide clearances required by
B149.1 or B149.2 Installation Code.

7. Installation guidelines

1. Codes — Install vent and combustion air piping in

compliance with all applicable national, state, local
or provincial codes.

2. Do not connect:

• Any other appliance to combustion air or vent
piping.

• Any other appliance into or through chimney
when using existing chimney as raceway.

• Multiple boilers into common vent.

3. Vent length limits — Position boiler as close as

possible to vertical vent/air run. Do not exceed vent
length limits given in Section 8 of this supplement.
B-vent limit is 30 feet. Vent or air max. lengths are:

• CGs-3 & CGs-4: Max 55 equivalent feet

• CGs-5 & CGs-6: Max 45 equivalent feet

Part Number 550-141-873/0502

4. Materials and construction —

• Seal all B-vent combustion air joints with

• Construct vent joints per vent manufacturer’s

• Use only one of the approved vent systems listed

5. Install boiler per CGs Boiler Manual.

approved silicone sealant (Dow Corning 700™
or 732™, General Electric 108 or 800, or sealant
specified by vent pipe manufacturer. B-vent

sections must be straight — no elbows

instructions, including use of their specified
sealant. Vent pipe routed inside B-vent must
also be fitted with vent clamps with elastomer
grippers, installed per section 9 of this
supplement.

in Table 2. Do not mix types of vent material.
CSA certification will be void.

.

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8. Verify vent system length

The vent or air piping must be no longer than the
maximum value given in
tables that the maximum length of connector piping
(vent or air piping between boiler and B-vent tee
connection) depends on the number of elbows and the
length of the B-vent section. The reason for this is that
each 90-degree vent or air pipe elbow cause the same
pressure drop as 7 feet of straight pipe.

Tables 4 and 5. Note in the

Vent/air piping length verification
procedure:

Step 1 — Determine dimensions of vent/air pipe
needed for planned location

Measure or calculate the vent/air pipe lengths required
for the planned location of the boiler and floor/roof
penetrations. See Figure 11 for a typical layout.

• How long will the vertical B-vent section have to be?
Round up to the nearest 5 feet (for example, if B-vent
length needs to be 12 feet, round this amount up to the
nearest 5 feet — use 15 feet for your B-vent length).
(This is dimension L in Figure 11.)

• How many elbows will be needed in the vent connector
piping (from boiler to B-vent tee)?

• How many feet of vent piping will be needed for the
connector runs?
(This would be the sum of dimensions C & D in Fig. 11.)

• How many elbows will be needed in the air connector
piping (from boiler to B-vent tee)?

• How many feet of air piping will be needed for the
connector runs?
(This would be the sum of dimensions A & B in Fig. 11.)

Step 4 — Replan boiler location & piping if piping
length of vent or air is too long

See if boiler can be moved closer to vertical vent/air
piping.

See if you can reduce the number of elbows required
vent piping must have 2 elbows minimum in order to
provide horizontal piping to install condensate drain
tee.

Example verification (

Step 1 — Vent/air piping required per plan

As an example, consider an installation of a CGs-5
boiler, where the boiler and vent/air locations would
require:

• Boiler model = CGs-5.

• B-vent length (L) = 20 feet.

• Vent connector piping requires 2 elbows.

• Vent connector piping length (D + C) = 16 feet.

• Air connector piping requires 1 elbow.

• Air connector piping length (B + A) = 17 feet.

Step 2 — Verify vent piping

• Enter Table 5 at the row for B-vent length of 20

feet.

• Move to the 2-elbow column.

• Read a maximum connector pipe length of 18 feet.

Conclusion — Vent piping is within limits because
vent connector piping would only be 16 feet (less than
the maximum of 18 feet).

Figure 11Figure 11

Figure 11):

Figure 11Figure 11

12

Step 2 — Verify that vent connector piping is within
allowable limits

Use Table 4 or 5, depending on boiler model to be used.
Find the row with the B-vent length the installation
requires. Move across to the column with the number
of vent elbows needed for the installation. This number
is the maximum allowable vent connector piping length.

Step 3 — Verify that air connector piping is within
allowable limits

Use Table 4 or 5, depending on boiler model to be used.
Find the row with the B-vent length the installation
requires. Move across to the column with the number
of air pipe elbows needed for the installation. This
number is the maximum allowable air pipe connector
piping length.

Step 3 — Verify air piping

• Enter Table 5 at the row for B-vent length of 20

feet.

• Move to the 1-elbow column.

• Read a maximum connector pipe length of 25 feet.

Conclusion — Air piping is within limits because air
connector piping would only be 17 feet (less than the
maximum of 25 feet).

Step 4 — Replanning

No replanning needed. Vent and air piping lengths are
within limits.

Part Number 550-141-873/0502

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enting — Venting — V

enting — V

enting — Venting — V

Maximum connector pipe length, vent or air:

• Combustion air connector pipe

• Vent connector pipe

CGs-3 and CGs-4

enting Supplemententing Supplement

enting Supplement

enting Supplemententing Supplement

Figure 11 Typical vent/air pipingTable 4 CGs-3 and CGs-4

“B-Vent”

length

(feet)

L

5 504336292215 8

10 45 38 31 24 17 10 3

15 40 33 26 19 12 5 --

20 35 28 21 14 7 -- --

25 30 23 16 9 2 -- --

30 25 18 11 4 -- -- --

Note: Combustion air connector pipe length = A + B

Vent connector pipe length = C + D

Total number of elbows

1 2 3 4 5 6 7

Max. length from boiler to “B-Vent”

Table 5 CGs-5 and CGs-6

Maximum connector pipe length, vent or air:

• Combustion air connector pipe

• Vent connector pipe

CGs-5 and CGs-6

L

L = B-vent length

A + B

C + D

A

= Combustion air

connector piping length

= Vent connector piping length

Elbow

“B-Vent”

length

(feet)

L

540332619125--

10 35 28 21 14 7 -- --

15 30 23 16 9 2 -- --

20 25 18 11 4 -- -- --

25 20 13 6 -- -- -- --

30 15 8 1 -- -- -- --

Note: Combustion air connector pipe length = A + B

Vent connector pipe length = C + D

Part Number 550-141-873/0502

Total number of elbows

1 2 3 4 5 6 7

Max. length from boiler to “B-Vent”

D

Vent piping

Condensate
drain line

Elbows

87304

C

B

Combustion air piping

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9. Installation — assembly

Step 1

Step 2

Assemble B-vent piping

1. Install 5" type B support, B-vent combustion air run,
flashing, fire stops and storm collar per
manufacturer’s instructions. Apply approved sealant
to each B-vent joint. See Figure 12.

2. Install type B draft hood connector to bottom of
combustion air run. Seal with approved sealant.

Prepare & insert vertical vent

1. From top or bottom of combustion air run, install

vent piping

• Top of vent piping must extend 3" above
top of rain cap. See Figure 5, page 8.

• Bottom of vent piping must extend 18"

below draft hood connector.

2. At each vent joint:

a. Follow vent pipe manufacturer’s instructions to

assemble and seal joints. Sealant recommended
by vent pipe manufacturer must be used as
indicated in their instructions.

b. Apply 2 self-adhesive elastomer grippers to vent

clamp. Grippers must be positioned on clamp
as shown in Figure 13. Bend out 2 ears on vent
clamp.

.

Figure 12 Sealing B-vent joints

87305

Figure 13 Apply elastomer strips to vent clamps

87306

Figure 14 Install vent clamps on vent piping

14

c. Fasten clamp around vent pipe with 2 – 1¹⁄₄"

screws in top and bottom holes, about every 5
feet. See Figure 14. Tighten screws until clamp
does not turn or slide around vent piping.

87307

Part Number 550-141-873/0502

VV

Draft hood
connector

Vent
support

87308

5” x 5” x 3”
Te e

Elastomer
flashing

Draft hood
connector

Bottom cap

87309

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V

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Step 3

Step 4

Install vent support

1. Apply 1 elastomer gripper to vent support.

2. Intall vent support around vent piping just below
draft hood connector as shown in Figure 15. Fasten
support around vent piping with 1 – 1 ¹⁄₄" screw.

3. Tighten screw until support does not turn or slide
around vent piping.

Install 5" x 5" x 3" tee

1. Slide tee over vent piping and attach uncrimped end
to bottom of draft hood connector:

a. Drill 3 holes in tee for ¹⁄₄" sheet metal screws.

Do not allow drill to
penetrate vent pipe. Drill

holes carefully in tee and use

1

only

/

" screws to fasten tee

4

to draft hood connector.
Failure to do so can damage
vent pipe, causing severe
personal injury or substantial
property damage.

b. Seal all seams and screws with approved sealant.

Figure 15 Install vent support

Figure 16 Install tee

2. Secure bottom cap to tee with duct tape. Slide
elastomer flashing up around vent pipe and tuck
lip into cap’s bottom opening. Seal with approved
sealant.

Follow vent pipe manufacturer's instructions to
assemble and seal joints. Sealant recommended by vent
pipe manufacturer must be used as indicated in their
instructions. Vent and combustion air connector piping
must be sealed gas-tight to prevent possibility of flue
gas spillage and carbon monoxide emissions, resulting
in severe personal injury or death.

Part Number 550-141-873/0502

15

GOLD CGs Gas-FGOLD CGs Gas-F

Vent pipe

Elastomer
flashing

Rain cap

87310

GOLD CGs Gas-F

GOLD CGs Gas-FGOLD CGs Gas-F

ired Wired W

ired W

ired Wired W

ater Boilerater Boiler

ater Boiler

ater Boilerater Boiler

9. Installation — assembly continued

Step 5 Install rain cap

1. On roof, cut 4 ¹⁄₂" hole in top of rain cap and
install cap over protruding vent pipe. Slide
elastomer flashing down around vent pipe
and tuck lip into cap’s top opening.

2. Connect termination coupling to vent pipe
using vent pipe manufacturer’s specified
sealant.

Step 6

Finish installation

1. Complete vent piping to boiler, making sure to follow vent pipe manufacturer’s instructions and Weil-McLain
vent manufacturers special gas vent system vent and combustion air venting supplements.

2. Use any of the following to install combustion air connector piping from tee to boiler, making sure to seal all
joints and seams:

a. 3" Flexible dryer vent — A piece of 3" galvanized is required at each end to adapt. Seal all pipe joints and

seams between pipe and dryer vent with approved sealant.
b. Galvanized or aluminum single wall pipe — Seal all joints and seams using approved sealant.
c. 3" PVC — Seal all joints using PVC cement.

Figure 17 Install rain cap

16

3. Condensate drain line — A condensate drain fitting is always required for through-roof vents. Follow vent

manufacturer’s instructions to install condensate drain line.

Use only silicone tubing rated for at least 400°F for the first 18" of condensate drain line, then
other non-metallic tubing may be used. Using any other material could cause flue gas leakage,
potentially resulting in severe personal injury, death or substantial property damage.

4. Multiple boilers may be vented with vent terminations at the same height. Space terminations to provide a
minimum of 1 fott between pipes for U.S. installations. For Canadian installations, provide clearances required
by B149.1 or B149.2 Installation Code.

Part Number 550-141-873/0502