Slant/Fin CHS-85 User manual

TABLE OF CONTENTS
CON EN S ...............................................PAGE
1.0 IN RODUC ION ............................................. 3
2.0 SPECIFICA IONS.............................................6
3.0 BOILER LOCA ION .........................................8
4.0 GENERAL VEN ING .....................................11
5.0 VEN /AIR-INLE ERMINA ION
CLEARANCES ...............................................25
6.0 CONDENSA E DRAIN .................................. 28
7.0 INS ALLING GAS PIPING .............................30
8.0 LIGH ING HE BOILER ................................32
9.0 GAS VALVE AND BURNER SE -UP ............. 34
10.0 BOILER AND HEA ING SYS EM PIPING ....37
11.0 FIELD WIRING ...............................................52
12.0 WIRING SCHEMA ICS...................................57
13.0 INS ALLA ION CHECKLIS .........................59
14.0 ANNUAL MAIN ENANCE AND
INSPEC ION .................................................60
15.0 ROUBLESHOO ING ...................................62
16.0 PAR S LIS ..................................................85
MODELS CHS-85 through CHS-399
INSTALLATION AND OPERATING INSTRUCTIONS
IMPORTANT
READ ALL OF THE FOLLOWING WARNINGS AND STATEMENTS
BEFORE READING THE INSTALLATION INSTRUCTIONS
his manual
must be left
with owner and
should be hung
on or adjacent
to the boiler
for reference.
®
C US
HIGH EFFICIENCY FIRE TUBE
CONDENSING GAS BOILER
©Sl nt/Fin Corp. 2013 • 613 • PUBLICATION CHS-40
He ting Contr ctor
Address
Phone Number
Boiler Model Number
Boiler Seri l Number
Inst ll tion D te
!
DANGER
Dange Sign: Indicates a haza dous situation which,
if not avoided, will esult in se ious inju y o death.
Wa ning Sign: Indicates a haza dous situation which,
if not avoided, could esult in se ious inju y o death.
Caution Sign plus Safety Ale t Symbol: Indicates a haza dous situa-
tion which, if not avoided, could esult in mino o mode ate inju y.
Caution Sign without Safety Ale t Symbol: Indicates a haza dous
situation which, if not avoided, could esult in p ope ty damage.
Notice Sign: Indicates a haza dous situation which, if
not avoided, could esult in p ope ty damage.
This Boile must be installed by a licensed and t ained Heating Techni-
cian o the Wa anty is Void. Failu e to p ope ly install thisunit may e-
sult in p ope ty damage, se ious inju y to occupants, o possibly death.
!
WARNING
!
CAUTION
CAUTION
NOTICE
!
WARNING

Slant Fin Corp. │ Installation and Operation Instructions CHS Series
2
Read Before Proceeding
If you do not follow these instructions exactly, a fire or explosion may result causing
property damage, serious injury or death.
FOR YOUR SAFETY, READ BEFORE OPERATING_
A) This boiler does not have a pilot. It is equipped with an ignition device which automatically lights the
burner. Do not try to light the burner by hand.
B) BEFORE OPERATING smell all around the boiler area for gas. Be sure to smell next to the floor
because some gas is heavier than air and will settle on the floor.
WHAT TO DO IF YOU SMELL GAS:
• Do not try to light any boiler.
• Do not touch any electric switch.
• Do not use any phone in your building.
• Immediately call your gas supplier from a neighbor's phone. Follow the gas supplier's instructions.
• If you cannot reach your gas supplier, call the fire department.
C) Use only your hand to turn the gas “shutoff” valve. Never use tools. If the handle will not turn by hand,
don't try to repair it, call a qualified service technician. Force or attempted repair may result in a fire or
explosion.
D) Do not use this boiler if any part has been under water. Immediately call a qualified service technician
to inspect the boiler and to replace any part of the control system and any gas control which has been
under water.
OPERATING INSTRUCTIONS_
1. STOP! Read the safety information above very carefully.
2. Set the thermostat to lowest setting. Turn off all electric power to the boiler.
3. This boiler does not have a pilot. It is equipped with an ignition device which automatically lights the
burner. Do not try to light the burner by hand.
4. Turn the manual gas valve to the OFF position. Remove front access panel.
5. Wait five (5) minutes to clear out any gas. Then smell for gas, including near the floor. If you smell gas,
STOP! Follow “B” in the safety information above. If you don't smell gas, go to the next step.
6. Turn the manual gas valve ON. Wait an additional five (5) minutes smelling for gas.
7. Replace the front access panel.
8. Set thermostat to highest setting. Turn on all electric power to the boiler.
9. Ignition sequence is automatic. Combustion will occur after a brief fan purge.
10. If ignition does not occur, follow the instructions “To Turn Off Gas To Boiler” and call your service
technician or gas supplier.
TO TURN OFF GAS TO THE BOILER_
1. STOP! Read the safety information above very carefully.
2. Turn off all electric power to the boiler.
3. Turn the manual gas valve to the OFF position.
Crystalline Silica - Certain components confined in the combustion chamber may
contain this potential carcinogen. Improper installation, adjustment, alteration, service or
maintenance can cause property damage, serious injury (exposure to hazardous materials) or death. Refer to
Section 14.0 for information on handling instructions and recommended personal protective equipment.
Installation and service must be performed by a qualified installer, service agency or the gas supplier (who must
read and follow the supplied instructions before installing, servicing, or removing this boiler. This boiler
contains materials that have been identified as carcinogenic, or possibly carcinogenic, to humans).
Void Warranty - This Boiler must have water flowing through it whenever the burner is
on or it will damage the unit and void the warranty. Failure to follow these instructions
may result in serious injury or death.

CHS Series Installation and Operation Instructions │ Slant Fin Corp.
3
1.0 INTRODUCTION
General Installation Requirements
The installation of your Slant/Fin CHS gas boiler must conform to the requirements of this manual, your local
authority, and the National Fuel Gas Code ANSI Z223.1 and or CAN/CGA B149 Installation Codes. Where
required by the Authority, the installation must conform to the standard for “Controls and Safety Devices for
Automatically Fired Boilers ANSI/ASME CSD-1.
This document pertains to the correct installation and operation of Slant/Fin boiler model CHS. The instructions
detailed in this document supersede any and all previous instructions provided by Slant/Fin, written or
otherwise. Each unit is provided with the following:
1. Installation and Operating Instructions,
2. Appendix A – Controller and Display Instructions,
3. CHS User Manual, and
4. Natural Gas to LP Conversion Kit*
* The conversion kit is required to convert the boiler so it will safely operate with Propane Gas.
Read and understand this entire document prior to proceeding with the installation of the
CHS boiler. Failure to follow the instructions outlined in this document will result in
property damage, serious injury or death.
User Responsibilities
This boiler must be installed and serviced by a qualified installer or service technician. This boiler must be
serviced and inspected annually when operating in normal residential applications. Demanding applications or
extreme conditions (i.e. commercial) may require more frequent service and inspection. As the User/Owner of
this equipment, you are responsible for ensuring the maintenance is performed at the required intervals (see
Section 14 – Annual Maintenance and Inspection).
Failure to have the boiler properly serviced and inspected on a regular basis by a qualified
service technician may result in property damage, serious injury or death.
Failure to keep the Vent and Combustion Air Intake clear of ice, snow, and other debris
may result in property damage, serious injury, or death.
Installer Responsibilities
As the installing technician it is your responsibility to ensure the installation is performed in accordance with this
instruction manual as well as any applicable local or National installation codes. It is also your responsibility to
inform the User/Owner of their obligation with respect to the above description under “User Responsibilities”.
Failure to follow this warning could result in fire, serious injury, or death.
Failure to use the appropriate Natural to LP Conversion Kit and Orifice when operating
the CHS with Propane will result in extremely dangerous burner operation leading to
property damage, serious injury or death. Refer to section titled ATTENTION: LIQUEFIED PETROLEUM
(LP) PROPANE for applicable conversion kit and LP orifice numbers.

Slant Fin Corp. │ Installation and Operation Instructions CHS Series
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ATTENTION: LIQUEFIED PETROLEUM (LP) PROPANE
The CHS boiler is factory set to operate with Natural Gas. BEFORE OPERATING WITH PROPANE, the
specified LP Conversion Kit and Orifice must be installed to convert the boiler so it will operate safely with
LP Propane. The correct kit and LP orifice is listed below (Each kit comes with conversion instructions).
Liquefied Petroleum (LP) propane gas is heavier than air; therefore, it is imperative that your CHS boiler is not
installed in a pit or similar location that will permit heavier than air gas to collect. Local Codes may require
boilers fueled with LP gas be provided with an approved means of removing unburned gases from the room.
Check your local codes for this requirement.
Natural to LP Propane Conversion Kit_
Model Number Kit Number LP Orifice
CHS-85 81 8124 000 415 (4.15mm)
CHS-110 81 8124 000 52 (5.2mm)
CHS-155-250 81 8124 000 62 (6.2mm)
CHS-300-399 81 8125 000 74 (7.4mm)
Boiler Vent / Air-Inlet Piping
The CHS boiler is certified as a “Category IV” boiler, and requires a “Special Venting
System” designed for pressurized venting. The exhaust gases must be piped directly to
the outdoors using the vent materials and rules outlined in these instructions. Failure to follow these instructions
will result in serious injury or death.
IN THE STATE OF MASSACHUSETTS ONLY
(a) For all horizontally vented gas fueled equipment installed in every dwelling, building or structure used in whole or
in part for residential purposes, including those owned and operated by the Commonwealth and where the side wall
exhaust vent termination is less than seven (7) feet above finished grade in the area of the venting, including but not
limited to decks and porches, the following requirements shall be satisfied:
1. INSTALLATION OF CARBON MONOXIDE DETECTORS At the time of installation of the side wall
horizontal vented gas fueled equipment, the installing plumber or gas fitter shall observe that a hard wired
carbon monoxide detector with an alarm and battery back-up is installed on the floor level where the gas
equipment is to be installed and on each additional level of the dwelling, building or structure served by the
equipment. It shall be the responsibility of the property owner to secure the services of qualified licensed
professionals for the installation of hard wired carbon monoxide detectors.
a. In the event that the side wall horizontally vented gas fueled equipment is installed in a crawl space or an
attic, the hard wired carbon monoxide detector with alarm and battery back-up may be installed on the next
adjacent floor level.
b. In the event that the requirements of this subdivision can not be met at the time of completion of
installation, the owner shall have a period of 30 days to comply with the above requirements; provided,
however, that during said 30 day period a battery operated carbon monoxide detector with an alarm shall
be installed.
2. APPROVED CARBON MONOXIDE DETECTORS Each carbon monoxide detector as required in accordance
with the above provisions shall comply with NFPA 720 and be ANSI/UL 2034 listed and IAS certified.
3. SIGNAGE A metal or plastic identification 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 boiler 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”
(plate included with boiler).
4. INSPECTION The state or local gas inspector of the side wall horizontally vented gas fueled equipment shall
not approve the installation unless, upon inspection, the inspector observes carbon monoxide detectors and
signage installed in accordance with the provisions of 248 CMR 5.08(2)(a)1 through 4.
…..Continued on Next Page

CHS Series Installation and Operation Instructions │ Slant Fin Corp.
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…..Continued.
(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 side wall 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) MANUFACTURER REQUIREMENTS – GAS EQUIPMENT VENTING SYSTEM PROVIDED: When the
manufacturer of Product Approved side wall horizontally vented gas equipment provides a venting system design or
venting system components with the equipment, the instructions provided by the manufacturer for installation of the
equipment and the venting system shall include:
1. Detailed instructions for installation of the venting system design or the venting system components; and
2. A complete parts list for the venting system design or venting system.
(d) MANUFACTURER REQUIREMENTS – GAS EQUIPMENT VENTING SYSTEM NOT PROVIDED:
When the manufacturer of a Product Approved side wall horizontally vented gas fueled equipment does not provide
the parts for venting the flue gases, but identifies “special venting systems”, the following requirements shall be
satisfied by the manufacturer:
1. The referenced “special venting system” instructions shall be included with the appliance or equipment
installation instructions; and
2. The “special venting system” 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 side wall horizontally vented gas fueled equipment,
all venting instructions, all parts list for venting instructions, and/or all venting design instructions shall remain with
the appliance or equipment at the completion of the installation.

Slant Fin Corp. │ Installation and Operation Instructions CHS Series
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2.0 SPECIFICATIONS
Table 2-1 CHS Specifications
DESCRIPTION
CHS-85
CHS-110
CHS-155
CHS-175
CHS-200
CHS-250
CHS-300
CHS-399
CSA Input Modulation
1,4
[MBH]
17-85
21.6-108
31-155
31-175
31-200
31-250
79.8-299
79.8-399
DOE Heating Capacity
1,2
[MBH]
78
99
144
163
185
230
278
380
Net I=B=R Rating
1,2
[MBH]
68
86
125
141
160
199
239
330
DOE AFUE2 [%]
95
95
95
94.8
94.7
94.5
94
95.4
Water Connections – NPT
[in.]
1
1-1/4
1-1/2
Gas Connection - NPT, in.
1/2
3/4
Vent/Air-inlet Pipe
Diameter
[in.] 3
2 or 3
3
4
Dimensions H x W x D [in.]
33-3/8 x 19-3/4 x 14-1/2
33-3/8 x 19-3/4 x 18-1/2
36-3/8 x 25-1/4 x 20
Approx. Boiler Weight
with Water [lbs]
110
180
250
Approx. Boiler Water
Content [Gallons]
3.2
4.9
6.4
Electrical Rating
120V/1Ph/60Hz/less than 12A
Notes:
1 Listed Input and Output ratings are at minimum vent lengths at an altitude of 0-2000ft. Numbers will be lower with
longer venting and/or altitudes greater then 2000ft.
2 Ratings based on standard test procedures prescribed by the U.S. Department of Energy; certified by AHRI. CHS-399
efficiency represents Thermal Efficiency (AFUE is not applicable).
3 The CHS requires a special venting system, use only vent materials and methods detailed in these instructions.
4 When operating with Propane models CHS-85 and CHS-110 have min/max Input Modulation rates of 17.6/88 and
22.6/113 MBH respectfully.
Wall mounting of unit requires two people to lift the boiler into place. Failure to follow
these instructions may result in property damage or personal injury.
High Altitude Operation
The CHS boiler is designed to operate at its maximum listed capacity in installations located at 0-2000ft above
Sea Level. Since the density of air decreases as elevation increases, maximum specified capacity should be de-
rated for elevations above 2000 ft [610 m] in accordance with Table 2-2.
Table 2-2 De-rate % for High Altitudes
Elevations
2001 ft [610 m]
3000 ft [914 m]
4000 ft [1219 m]
4500 ft [1372 m]
5000 ft [1524 m]
In Canada
1
de-rate by 10%
de-rate by 10%
de-rate by 10%
de-rate by 10%
de-rate % may vary
In USA
2
-
de-rate by 4%
de-rate by 8%
de-rate by 8%
de-rate by 12%
Notes:
1 Canada: Altitudes between 2000-4500 ft [610-1372 m], de-rate by 10%. Consult local authorities for de-rating
capacities for altitudes above 4500 ft [1372 m].
2 USA: De-rate capacity by 4% for every 1000 ft [305 m] over 2000 ft [610 m].
Combustion – At elevations above 2000 feet, the combustion of the boiler must be
checked with a calibrated combustion analyzer to ensure safe and reliable operation. It is
the Installers responsibility to check the combustion and to adjust the combustion in accordance with
Section 9.0. Failure to follow these instructions may result in property damage, serious injury, or death.

CHS Series Installation and Operation Instructions │ Slant Fin Corp.
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Figure 2-1 CHS-85-110 Dimensions & Specifications
Figure 2-2 CHS-155-250 Dimensions & Specifications
Figure 2-3 CHS-300-399 Dimensions & Specifications

Slant Fin Corp. │ Installation and Operation Instructions CHS Series
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3.0 BOILER LOCATION
In all cases, the CHS boiler must be installed indoors in a dry location where the ambient temperature must be
maintained above freezing and below 100F [38C]. All boiler components must be protected from dripping,
spraying water, or rain during operation and servicing. Consider the proximity of system piping, gas and
electrical supply, condensate disposal drain, and proximity to vent termination when determining the best boiler
location.
Water or flood damaged components must be replaced immediately with new factory-
approved components as failure to do so may result in fire, serious injury, or death.
Boiler Area Ventilation Air Openings
If boiler area clearances are less than the recommended clearances specified in Table 3-1, the boiler area must be
ventilated (Exception: if the boiler area/room has a volume of 150 ft3 or greater, ventilation of the boiler room is
not required). Each ventilation air opening must meet the minimum requirements of 1 in2 per 1000 Btu/hr, but
not less then 100 in2. The lower ventilation opening must be located within 6” of the floor while the upper
opening must be located 6” from the top of the space.
If the "Boiler Area" does not meet the recommended clearances listed in Table 3-1, and if
the boiler area has a volume less than 150 ft3, it is considered a Closet or Alcove. In US /
Canada, PVC vent pipe and fittings shall not be used within the closet or alcove; only
approved CPVC, Polypropylene or Stainless Steel vent pipe and fittings can be used. See Table 4-4 for a list of
approved materials. Under all circumstances, the minimum clearances listed in Table 3-1 must be provided.
Closet Installations
For closet installations it is necessary to provide two ventilation air openings as shown in Figure 3-1, each
providing a minimum area equal to 1 in2 per 1000 Btu/hr, but not less then 100 in2 and within 6” of the top and
bottom of the closet door. See Table 3-1 for minimum clearances.
Alcove Installations
Alcove installations have the same minimum clearances as closet installations, except the front must be
completely open to the room at a distance no greater then 18” [457 mm] from the front of the boiler and the
room is at least three (3) times the size of the alcove. Provided these conditions are met, the boiler requires no
extra ventilation air openings to the space. See Table 3-1for minimum clearances.
Residential Garage Installations
When installed in a residential garage, mount the boiler a minimum of 18” [457 mm] above the floor. Locate or
protect the boiler so it cannot be damaged by a moving vehicle. Check with your local authorities for other
possible regulations pertaining to the installation of a boiler in a garage.
Wall Mounting Installations
The CHS is provided with integrated wall mounting brackets. Refer to Figure 3-2 for instructions and
illustrations on wall mounting.
Table 3-1 Minimum Clearances for Installation and Service
Model No.
Clearances
Dimensions - inches [mm]
Front
Top
Sides
Back
Bottom
Flue Pipe
CHS 85-399
Minimum
24 [610]
1
12 [305]
4 [102]
0
9 [229]
1 [25]
Recommended
36 [914]
24 [610]
12 [305]
0
24 [610]
1 [25]
Notes:
1 6” if surface is removable allowing a minimum of 24” [610 mm] clearance (i.e. closet installation). See Ventilation Air
Opening dimensions in Figure 3-1.
Closet/alcove installations in US and Canada require approved CPVC, Polypropylene or
Stainless Steel vent and air-inlet pipe and fittings (see Table 4-4); PVC is not permitted.
Failure to follow these instructions may result in damage or serious injury.

CHS Series Installation and Operation Instructions │ Slant Fin Corp.
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Figure 3-1 Closet Installation, Minimum Clearances
(Model CHS 85-110 Shown)
Front = 6”
(if removable)
Ventilation Air Openings
are not required if the
boiler area meets the
Recommended Clearances
listed in Table 3-1.
Bottom ventilation opening
Max. 6” above floor / bottom
Top ventilation opening
Max. 6” below ceiling / top
Sides = 4”
Removable surface /
closet door
Ventilation air opening
1in2 per 1000 Btu/hr,
min. 100in2
Ventilation air opening
1in2 per 1000 Btu/hr,
min. 100in2
Min. 1” clearance for hot
water and vent pipes
Bottom = 9”
Top = 12”

Slant Fin Corp. │ Installation and Operation Instructions CHS Series
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Figure 3-2 Wall Mounting Instructions
 While leaving the Upper bracket (A) intact,
remove the Wall-mount bracket (B) attached
to the bottom-back of the appliance. Save the
mounting hardware for Step 4.
 Secure the Wall-mount bracket (B), removed
from the bottom of the boiler in Step 1, to a
solid wall using field supplied lag screws
(anchors when mounting to a concrete wall)
that are adequate to support the weight of the
appliance (refer to Table 2-1 Specifications).
Ensure the Wall-mount bracket is mounted
level and flush to the wall with mounting holes
on the bottom, flange pointed upward and
angled away from the wall.
 Mount the appliance to the wall by aligning the
Upper bracket (A) with the Wall-mount
bracket (B). Slide the Upper bracket down
over the wall mount bracket until it hooks.
 Once the appliance is resting securely on the
Upper bracket, secure the Bottom bracket (C)
to the underside of the appliance using the
mounting hardware removed in Step 1; then,
anchor the bottom bracket to the wall as shown
using field supplied hardware.
Failure to follow instructions may
result in fire, serious injury, or death.
This unit requires two people to lift it
or damage and injury may result.
Upper bracket (A)
Wall-mount
bracket (B)



Wall-mount
bracket (B)

Wall
Boiler
Ensure bracket
(A) fully inserts
into bracket (B)
(B)
(A)
Bottom bracket (C) shipped
with boiler package

CHS Series Installation and Operation Instructions │ Slant Fin Corp.
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4.0 GENERAL VENTING
The CHS boiler is certified as a “Category IV” boiler requiring a “Special Venting System” designed for
pressurized venting. The Exhaust Vent must be piped to the outdoors, using the vent materials and rules outlined
in this section. Under no conditions may this unit vent gases into a masonry chimney, unless it is vacant, and
utilizes the approved venting material and rules described in this section.
Vent and Air-inlet are to be piped separately. The CHS cannot share a common vent or
air-inlet with multiple boilers. Failure to comply will result in serious injury or death.
Direct Vent Installation (Best Practice)
When installed as a Direct Vent boiler the combustion air-inlet must also be piped directly to the outdoors using
the methods described in this section and in accordance with the National Fuel Gas Code, ANSI Z223.1 (U.S.) or
CSA B149.1 (Canada) and local requirements.
Installation Using Indoor Combustion Air
When the installation uses Indoor Combustion Air (i.e. piping is not directly connecting the appliance air-inlet
fitting to the outdoors), the combustion air-inlet is drawn from Indoors or Outdoors via the appliance area using
the methods described in this section and in accordance with the National Fuel Gas Code, ANSI Z223.1 (U.S.) or
CSA B149.1 (Canada) and local requirements.
The boiler shall be located so as not to interfere with proper circulation of combustion,
ventilation, and dilution air.
Make up air requirements for the operation of exhaust fans, kitchen ventilation systems,
clothes dryers, and fireplaces shall be considered in determining the adequacy of a space
to provide combustion air requirements. Failure to ensure adequate make up air to all
appliances may result in personal injury or death.
Indoor Combustion Air - Opening Size and Location: The methods detailed below for determining Opening
Size and Location for accessing indoor combustion air, shall be used when the air infiltration rate is adequate, i.e.
greater than 0.4 ACH (air changes per hour) and when the boiler area and communicating spaces have a
minimum volume of 50 cubic ft per 1000 Btu/hr. If the air infiltration rate is known to be less that 0.4 ACH,
refer to the National Fuel Gas Code for further guidance.
1. Combined spaces on the same story – Each opening shall have a minimum free area of 1 in.2/1000 Btu/hr
of the total input rating of all appliances in the space, but not less than 100 in.2. One opening shall
commence within 12 in. of the top, and one opening shall commence within 12 in. of the bottom, of the
enclosure, see Figure 4-1a. The minimum dimension of air openings shall be not less than 3in.
2. Combined spaces in different stories – The volumes of spaces in different stories shall be considered as
communicating spaces where such spaces are connected by one or more openings in doors or floors having a
total minimum free area of 2 in.2/1000 Btu/hr of total input rating of all appliances.
Outdoor Combustion Air – Opening Size and Location: Outdoor combustion air shall be provided through
opening(s) to the outdoors in accordance with the methods detailed below. The minimum dimension of air
openings shall not be less than 3in.
1. Two Permanent Openings Method – Two permanent openings, one commencing within 12in. of the top,
and one commencing within 12in. of the bottom of the enclosure, shall be provided. The openings shall
communicate directly, or by ducts, with the outdoors or spaces that freely communicate with the outdoors, as
follows:
a. Where communicating with the outdoors or where communicating to the outdoors through vertical ducts,
each opening shall have a minimum free area of 1 in.2/4000 Btu/hr of total input rating of all appliances
in the enclosure; see Figures 4-1b and 4-1c.
b. Where communicating with the outdoors through horizontal ducts, each opening shall have a minimum
free area of 1 in.2/2000 Btu/hr of total input rating of all appliances in the enclosure; see Figure 4-1d.
2. One Permanent Opening Method – One permanent opening, commencing within 12 in. of the top of the
enclosure, shall be provided. The appliance shall have clearances of at least 1 in. from the sides and back

Slant Fin Corp. │ Installation and Operation Instructions CHS Series
12
and 6 in. from the front of the appliance. The opening shall directly communicate with the outdoors or shall
communicate through a vertical or horizontal duct to the outdoors or spaces that freely communicate with the
outdoors (see Figure 4-1e) and shall have a minimum free area of the following:
a. 1 in.2/3000 Btu/hr of the total input rating of all appliances located in the enclosure, and
b. Not less than the sum of the areas of all appliance vent connectors in the space.
3. Combination Indoor and Outdoor Combustion Air – The use of a combination of indoor and outdoor
combustion air shall be in accordance with the following:
a. Indoor Openings – where used, openings connecting the interior spaces shall comply with “Indoor
Combustion Air – Opening and Size and Location” described above.
b. Outdoor Openings – Outdoor opening(s) shall be located in accordance with “Outdoor Combustion Air
– Opening Size and Location” described above.
c. Outdoor Opening(s) Size – The outdoor opening(s) size shall be calculated in accordance with the
following:
i. The ratio of interior spaces shall be the available volume of all communicating spaces divided by the
required volume (i.e. 50 cubic ft per 1000 Btu/hr if 0.4 ACH or greater).
ii. The outdoor size reduction factor shall be 1 minus the ratio of interior spaces.
iii. The minimum size of outdoor opening(s) shall be the full size of outdoor opening(s) calculated in
accordance with “Outdoor Combustion Air – Opening Size and Location” described above, multiplied
by the reduction factor. The minimum dimension of air openings shall not be less than 3 in.
Figure 4-1(a) Indoor Air
Figure 4-1(b) Two Vertical Ducts
Figure 4-1(c) Two Vertical Duct
Figure 4-1(d) Two Horizontal Ducts
Figure 4-1(e) One Duct Options
Opening (within
1ft of ceiling)
Opening (within
1ft of floor)
Exhaust Vent
Opening
Opening
Exhaust Vent
Ventilation Louvers
(each end of attic)
Ventilated & unheated
crawl space
Exhaust Vent
Ventilation Louvers
(each end of attic)
Opening
Opening (duct
extended to within
1ft of floor)
Exhaust Vent
Opening (within
1ft of ceiling)
Opening (within
1ft of floor)
Exhaust Vent
Ventilation Louvers
(each end of attic)
Opening Option B
(within 1ft of ceiling)
Opening Option A

CHS Series Installation and Operation Instructions │ Slant Fin Corp.
13
Combustion Air-inlet Contamination
Be careful not to locate the air-inlet termination in an area where contaminants can be drawn in and used for
combustion. Combustion air containing dust, debris or air-borne contaminants will drastically increase the
required maintenance and may cause a corrosive reaction in the Heat Exchanger which could result in premature
failure, fire, serious injury, or death. See Table 4-1 for a list of areas to avoid when terminating air-inlet piping:
Table 4-1 Corrosive Products and Contaminant Sources
Products to Avoid
Contaminated Sources to Avoid
Antistatic fabric softeners, bleaches, detergents, cleaners
Laundry facilities
Perchloroethylene (PCE), hydrocarbon based cleaners
Dry cleaning facilities
Chemical fertilizer, herbicides/pesticides, dust, methane gas
Farms or areas with livestock and manure
Paint or varnish removers, cements or glues, sawdust
Wood working or furniture refinishing shops
Water chlorination chemicals (chloride, fluoride)
Swimming pools, hot tubs
Solvents, cutting oils, fiberglass, cleaning solvents
Auto body or metal working shops
Refrigerant charge with CFC or HCFC
Refrigerant repair shops
Permanent wave solutions
Beauty shops
Fixer, hydrochloric acid (muriatic acid), bromide, iodine
Photo labs, chemical / plastics processing plants
Cement powder, crack fill dust, cellulose, fiber based insulation
Concrete plant or construction site
Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this
or any other boiler. Failure to follow instructions may result in serious injury or death.
It is BEST PRACTICE to pipe the combustion air-inlet directly to the outdoors (Direct
Vent installation) to avoid contamination often contained in indoor air.
Flammable Solvents and Plastic Piping
Due to the extremely flammable characteristics of most glues, cements, solvents and primers used in the process
of joining plastic vent and air-inlet pipe, explosive solvent vapors must be evacuated from the vent and air-inlet
prior to start-up. Avoid using excess cement or primer that may lead to pooling inside the pipe assembly. Freshly
assembled piping assembly should be allowed to cure for a minimum of 8 hours before applying power to the gas
fired boiler. Refer to Mandatory Pre-commissioning Procedure for Plastic Venting in this section.
Flammable Cements and Primers – It is the installers’ responsibility to familiarize
themselves with the hazards associated with explosive solvents and to take all precautions
to reduce these risks. Failure to follow these instructions can cause explosions, property damage, injury or death.
Near Boiler Vent/Air-inlet Piping
Each CHS boiler is equipped with a short piece of approved CPVC vent pipe which is to be used when venting
with PVC. Insert one end into the boiler flue outlet adapter and cement the other to the field venting (see Table 4-
4 for approved venting material). The CPVC vent pipe should extend fully into the boiler flue outlet adapter (see
Table 4-2). DO NOT insert PVC pipe directly into the flue outlet connection as it can deform from the clamping
force of the gear clamp. Ensure that the venting system does not apply a load or strain on the boiler flue outlet
adapter. The manufacturer recommends using two elbows to create a “swing joint” to reduce potential strain on
vent piping and cemented joints. See Figures 4-2 through 4-4 for illustrations.
Gasket Seating - Improper seating can cause leakage and eventual failure of the sealing
gasket. Ensure the vent pipe is adequately beveled prior to inserting into the boiler flue
adapter. Failure to follow these instructions may result in serious injury or death.

Slant Fin Corp. │ Installation and Operation Instructions CHS Series
14
Figure 4-2(a) CHS 85-110 & 300-399
Figure 4-2(b) CHS 85-110 & 300-399
Near Boiler Venting (CPVC)
Near Boiler Venting (PVC)
Figure 4-2(c) CHS 155-250
Figure 4-2(d) CHS 155-250
Near Boiler Venting (CPVC)
Near Boiler Venting (PVC)
 Air-inlet - check with applicable local codes for acceptable pipe material.
Exhaust venting must be supported to reduce strain on piping joints. Failure to follow
these instructions may result in result in damage, serious injury or death.
In Canada, the first 3 ft (915 mm) of vent piping must be readily accessible for inspection.
PVC Coupling
Air Inlet
Adapter
(factory
supplied)
Swing Joint to attain
slope in horizontal runs
PVC Exhaust Vent -
(check local codes
and Table 4-3)
Mandatory Vent Pipe
Transition Pipe
See Table 4-2.
Air-inlet
Pipe *
CPVC Transition
Pipe - minimum 5”
long (factory supplied)
Flue Outlet
Adapter (factory
supplied)
Flue Outlet
Adapter (factory
supplied)
CPVC Exhaust
Vent
Swing Joint
to attain slope in
horizontal runs
Air-inlet
Pipe *
Air Inlet
Adapter
(factory
supplied)
PVC Coupling
Air Inlet
Adapter
(factory
supplied)
Swing Joint
to attain slope in
horizontal runs
PVC Exhaust Vent -
(check local codes
and Table 4-3)
Mandatory Vent Pipe
Transition Pipe
See Table 4-2.
Air-inlet
Pipe *
CPVC Transition
Pipe - minimum 5”
long (factory supplied)
Flue Outlet
Adapter (factory
supplied)
Flue Outlet
Adapter (factory
supplied)
CPVC Exhaust
Vent
Swing Joint
to attain slope in
horizontal runs
Air-inlet Pipe *
Air Inlet Adapter
(factory supplied)

CHS Series Installation and Operation Instructions │ Slant Fin Corp.
15
Figure 4-2(e) CHS 85-110 & 300-399
Figure 4-2(f) CHS 85-110 & 300-399
Near Boiler Venting (Stainless Steel)
Near Boiler Venting (Polypropylene)
Figure 4-2(g) CHS 155-250
Figure 4-2(h) CHS 155-250
Near Boiler Venting (Stainless Steel)
Near Boiler Venting (Polypropylene)
 Air-Inlet - check with applicable local codes for acceptable pipe material.
Exhaust venting must be supported to reduce strain on piping joints. Failure to follow
these instructions may result in result in damage, serious injury or death.
In Canada, the first 3 ft (915 mm) of vent piping must be readily accessible for inspection.
Flue Outlet
Adapter (factory
supplied)
SS Exhaust
Vent
Swing Joint
to attain slope in
horizontal runs
SS Air-inlet Pipe
FasNSeal Appliance
Adapter (see Table 4-3)
Air Inlet Adapter
(factory supplied)
Flue Outlet
Adapter (factory
supplied)
SS Exhaust
Vent
Swing Joint
to attain slope in
horizontal runs
SS Air-inlet Pipe
SS Appliance Adapter
(see Table 4-3)
Air Inlet Adapter
(factory supplied)
Air-inlet Adapter
(factory supplied)
PPS Elbow
w/ offset angle to
account for slope
PPS Exhaust Vent
PPS Air-inlet Pipe*
PPS Appliance Adapter
(see Table 4-3)
Flue Outlet Adapter
(factory supplied)
PPS Appliance Adapter
(see Table 4-3)
Air Inlet Adapter
(factory supplied)
PPS Elbow
w/offset angle to
account for slope
PPS Exhaust Vent
PPS Air-inlet Pipe*
Flue Outlet Adapter
(factory supplied)

Slant Fin Corp. │ Installation and Operation Instructions CHS Series
16
Table 4-2 CPVC Vent Pipe Transition Piece (used when venting with PVC)
Model No.
Vent Pipe Size
CPVC Transition Vent Pipe Length
Full Insertion Depth
CHS 85-110
3”
Minimum 5” [127 mm]
2-7/8” [73 mm]
CHS 155-250
3”
Minimum 5” [127 mm]
2-5/8” [67 mm]
CHS 300-399
4”
Minimum 5” [127 mm]
2-5/8” [67 mm]
Table 4-3 Appliance Adapters for Polypropylene and Stainless Steel Venting
Model No.
Vent Material
Venting Brand
Adapter Part No. 1,2
CHS 85-250
Polypropylene
DuraVent – PolyPro
300150
Centrotherm - InnoFlue
ISAA0303
Stainless Steel
DuraVent – FasNSeal
300715
CHS 300-399
Polypropylene
DuraVent – PolyPro
300151
Centrotherm - InnoFlue
ISAA0404
Stainless Steel
DuraVent – FasNSeal
303631
Notes:
1 Listed appliance adapters are only approved for use with the respective venting brand; i.e. a PolyPro appliance adapter
shall not be used with InnoFlue venting.
2 PolyPro and FasNSeal appliance adapters are available from DuraVent (1-800-835-4429 or www.duravent.com);
InnoFlue appliance adapters are available from Centrotherm Eco Systems (1-877-434-3432 or www.centrotherm.us.com).
Vent/Air-inlet Pipe Material
Table 4-4 Acceptable Vent and Air-Inlet Pipe Material
Items 1
Materials 2, 3
Venting System Standards
All Vent and Air-Inlet
materials installed on gas
fired appliances in CAN/US
must meet the Standards
listed in this Table. Failure
to comply could result in
fire, serious injury or death.
United States
Canada 4
Vent Piping
and Fittings
PVC - DWV
ANSI/ASTM D2265
All venting material in
Canada must be
ULC S636 approved.
See Note 4 below for
appropriate temperature
applications.
PVC Schedule 40
ANSI/ASTM D1785
CPVC Schedule 40
ANSI/ASTM F441
Stainless Steel (SS)
UL-1738
Polypropylene (PP)
-
Pipe Cement
PVC
ANSI/ASTM D2564
CPVC
ANSI/ASTM F493
Primers
PVC / CPVC
ANSI/ASTM F656
Notes:
1 Refer to Table 4-5 for Allowable Vent and Air-Inlet Pipe Sizes and Lengths.
2 PVC venting (exhaust and air-inlet) is not permitted within the Closet/alcove of a Closet/alcove installation.
3 The Air-inlet does not require high temperature pipe material. Check applicable local codes for acceptable materials.
4 ULC S636 PVC is approved for flue gas temperatures up to 149oF (65oC) and must only be used for low temperature
applications. High temperature applications requiring boiler supply water temperatures greater than 140oF (60oC) must
use ULC S636 CPVC, PP or SS.
The use of cellular core PVC (ASTM F891), cellular core CPVC, or Radel®
(polyphenolsulfone) in the exhaust venting system is prohibited. Failure to follow these
instructions may result in property damage, personal injury or death.
Covering non-metallic vent pipe and fittings with thermal insulation is prohibited. Failure
to follow these instructions may result in property damage, personal injury or death.

CHS Series Installation and Operation Instructions │ Slant Fin Corp.
17
Mandatory Pre-commissioning Procedure for Plastic Venting (PVC or CPVC)
Do not apply power to the boiler prior to Step 4 in the Mandatory Pre-commissioning
Procedure for Plastic Venting.
1) Working with the power turned off to the boiler, completely install the vent and air intake system, securely
cementing joints together. If possible, allow primers/cements to cure for 8 hours before firing the burner. If
curing time is less than 8 hours, proceed with Steps 2 through 6.
2) Maintain the boiler gas supply shut-off valve in the off position.
3) Remove the cable from the Spark Ignition Transformer.
Spark Ignition Circuit - Maintain a safe distance (2 inches minimum) from the spark
ignition circuit to avoid injury from electrical shock.
4) Turn power on to the boiler and apply a heat demand.
5) Allow for 3 complete trials for ignition, consisting of pre and post purge of the combustion blower, until an
ignition lockout occurs. Repeat the process two more times (i.e. 9 complete ignition sequences in total).
6) Turn power off and reconnect the cable to the Spark Ignition Transformer.
Vent/Air-inlet Pipe Length Determination
Use Table 4-5 to determine the maximum pipe length that can be used. The table calculates 90º elbows, and 45º
elbows at 5 equivalent feet each.
Example: When using 3” pipe, a CHS 85-110 can be installed with 150 equivalent feet of air-inlet piping and
150 equivalent feet of exhaust-vent piping. See Table 4-5 for more details.
Models CHS 85-110 require a minimum equivalent exhaust vent length of 15’. When
operating on Propane, models CHS 85-110 require a minimum air-inlet length of 6’ and
11’ for 2” and 3” venting respectfully.
Table 4-5 Allowable Vent and Air-inlet Pipe Size and Lengths
Model No.
Pipe
Size
Gas
Length
(ft)
Number of Elbows (90’s or 45’s) and Equivalent Feet
1
2
3
4
5
6
7
8
9
CHS 85-110
2” 1
NG
100
95
90
85
80
75
70
65
60
55
CHS-85
LP
35
30
25
20
15
10
5
-
-
-
CHS-110
25
20
15
10
5
-
-
-
-
-
CHS 85-110
3”
NG/LP
150
145
140
135
130
125
120
115
110
105
CHS 155-250
100
95
90
85
80
75
70
65
60
55
CHS 300-399
4”
100
95
90
85
80
75
70
65
60
55
Note:
1 See WARNING below.
PVC Exhaust Venting – When using 2” PVC venting with models CHS 85-110, the first
seven (7) equivalent feet of exhaust venting must be approved 2” CPVC or 3” PVC; see
exceptions in Table 4-4 and Figures 4-2b and 4-2d.

Slant Fin Corp. │ Installation and Operation Instructions CHS Series
18
Termination Options – Direct Vent Installation
The venting system of the CHS may be terminated using field supplied piping to construct a “Two-Pipe”
termination, see Figures 4-3a, 4-4a, 4-4d, 4-5a, 4-6a and 4-6d; alternatively the venting may be terminated using
a factory kit selected from Table 4-6. The “IPEX Low Profile” kit (see Figures 4-3b and 4-5c) and “M&G
DuraVent Concentric (Wall)” kit (see Figures 4-3d and 4-5d) can be used for Sidewall terminations, while the
“M&G DuraVent Concentric (Roof)” kit (see Figures 4-4c and 4-6c) can be used for Rooftop terminations; the
“IPEX Concentric” kit (see Figures 4-3c, 4-4b, 4-5b and 4-6b) can be used for either Sidewall or Rooftop
terminations.
Venting Options - Due to potential moisture loading (build-up) along the exterior wall,
sidewall venting may not be the preferred venting option (see Figures 4-4 and 4-6).
Optional Termination Kits – Direct Vent Installation
Kits certified with the CHS boiler are listed in Table 4-6 and available from IPEX, DuraVent and/or Slant/Fin.
For more information on System 636 Vent Kits or wholesaler locations contact IPEX directly USA: 1-800-463-
9572 or www.IPEXamerica.com │ CAN: 1-866-473-9462 or www.ipexinc.com. For more information on
PolyPro Vent Kits or wholesaler locations contact DuraVent directly 1-800-835-4429 or www.duravent.com.
Table 4-6 Optional Vent Termination Kits
Description
Vent
Size
Vent Material
Slant/Fin
P/N
Supplier
P/N
Boiler Models
Vent Option
Roof
Wall
IPEX Low Profile
(Flush Mount)7
2”
PVC/CPVC 7
196984
CHS 85-110


3”
81 8171 000
196985
CHS 85-250
4”
81 8174 000
196986
CHS 300-399
IPEX Concentric
(Wall/Roof)5,6,7
2”
PVC
196005
CHS 85-110


3”
81 8173 000
196116
CHS 85-250
CPVC
197009
4”
PVC
81 8175 000
196021
CHS 300-399
DuraVent - PolyPro
Concentric (Wall)
2”
PVC/CPVC/PP
2PPS-HK
CHS 85-110


3”
3PPS-HK
CHS 85-250
4”
4PPS-HK
CHS 300-399
DuraVent - PolyPro
Concentric (Roof)
2”
2PPS-VK
CHS 85-110


3”
3PPS-VK
CHS 85-250
4”
4PPS-VK
CHS 300-399
Notes:
1 Instructions included with termination kits contain detailed assembly and installation instructions.
2 All factory termination kits are ULC S636 approved.
3 Clearance requirements in this manual supersede those of the instructions included with the vent terminal.
4 Piping MUST be secured to the vent terminal during installation.
5 IPEX Concentric Terminal MUST be cemented together and to the vent pipes during installation.
6 Vent Screens provided with boiler may be used with the IPEX Concentric Vent Kits; otherwise use IPEX vent screens
(2” vent screen P/N 196050; 3" vent screen P/N 196051; 4" vent screen P/N 196052 – each sold separately).
7 IPEX Low Profile and Concentric kits (excluding p/n 197009) are constructed out of ULC S636 approved PVC; check
with your local authority for the acceptance of PVC as a venting material prior to use.

CHS Series Installation and Operation Instructions │ Slant Fin Corp.
19
Sidewall Venting Options – Direct Vent Installation
Figure 4-3(a)
Figure 4-3(b)
Two-pipe Termination (Sidewall)
IPEX Low Profile Termination (Sidewall)
Figure 4-3(c)
Figure 4-3(d)
IPEX Concentric Termination (Sidewall)
DuraVent Concentric Termination (Sidewall)
Location of exhaust and air-inlet
connections vary between
models, see Figure 4-2.
(model CHS 85-110 shown)
Exhaust
Inlet
Location of exhaust and air-inlet
connections vary between
models, see Figure 4-2.
(model CHS 85-110 shown)
Exhaust
Inlet
Location of exhaust and air-inlet
connections vary between
models, see Figure 4-2.
(model CHS 85-110 shown)
Exhaust
Inlet
Location of exhaust and air-inlet
connections vary between
models, see Figure 4-2.
(model CHS 85-110 shown)
Exhaust
Inlet

Slant Fin Corp. │ Installation and Operation Instructions CHS Series
20
Roof Venting Options – Direct Vent Installation
Figure 4-4(a)
Figure 4-4(b)
Two-pipe Termination (Roof)
IPEX Concentric Termination (Roof)
Figure 4-4(c)
Figure 4-4(d)
DuraVent Concentric Termination (Roof)
Two-pipe Termination (Roof-exhaust / Sidewall-inlet)
Location of exhaust and air-inlet
connections vary between
models, see Figure 4-2.
(model CHS 85-110 shown)
Exhaust
Inlet
Location of exhaust and air-inlet
connections vary between
models, see Figure 4-2.
(model CHS 85-110 shown)
Exhaust
Inlet
Location of exhaust and air-inlet
connections vary between
models, see Figure 4-2.
(model CHS 85-110 shown)
Exhaust
Inlet
Location of exhaust and air-inlet
connections vary between
models, see Figure 4-2.
(model CHS 85-110 shown)
Exhaust
Inlet