CleaverBrooks ClearFire CFLC-5000 User manual

Model CFLC
ClearFire
Condensing Boiler
Operation and Maintenance Manual
750-363
08/2017
4,000 - 12,000 MBTU

ii
Do not use this boiler if any part has been under
water. Immediately call your Cleaver-Brooks ser-
vice representative to inspect the boiler and to re-
place any part of the control system and any gas
control which has been under water.
!DANGER
WARNING
!DANGER
WARNING
If the information in this manual is not fol-
lowed exactly, a fire or explosion may re-
sult causing property damage, personal
injury or loss of life.
— Do not store or use gasoline or other
flammable vapors and liquids in the vicin-
ity of this or any other appliance.
— WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electrical 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.
— Installation and service must be performed by
a qualified Cleaver-Brooks, service agency or the
gas supplier.
Improper installation, adjustment, ser-
vice, or maintenance can cause equip-
ment damage, personal injury, or death.
Refer to the Operation and Maintenance
manual provided with the boiler. Installa-
tion and service must be performed by a
qualified Cleaver-Brooks service provid-
!DANGER
WARNING
!DANGER
WARNING
Be sure the fuel supply which the boiler
was designed to operate on is the same
type as specified on the boiler name
plate.
!DANGER
WARNING
Should overheating occur or the gas sup-
ply valve fail to shut off, do not turn off or
disconnect the electrical supply to the
boiler. Instead turn off the gas supply at a
location external to the boiler.
!DANGER
WARNING
To minimize the possibility of serious personal in-
jury, fire or damage to the equipment, never vio-
late the following safety rules.
— Always keep the area around the boiler free of
combustible materials, gasoline, and other flam-
mable liquids and vapors
—Nevercovertheboiler,leananythingagainstit,
stand on it, or in any way block the flow of fresh
air to the boiler.
This manual must be maintained in legible condi-
tion and kept adjacent to the boiler or in a safe
place for future reference. Contact your local
Cleaver-Brooks representative if additional manu-
als are required.
Notice
Where required by the authority having jurisdic-
tion, the installation must conform to the Standard
for Controls and Safety Devices for Automatically
Fired Boilers, ANSI/ASME CSD-1.
Notice
The boiler and its individual shutoff valve must be
disconnected from the gas supply piping system
during any pressure testing of that system at test
pressures in excess of 1/2 psi (3.5 kPa).
!DANGER
WARNING
The installation must conform to the requirements
of the authority having jurisdiction or, in the ab-
sence of such requirements, to UL 795 Commer-
cial-Industrial Gas Heating Equipment and/or the
National Fuel Gas Code, ANSI Z223.1
!DANGER
WARNING

iii
Please direct purchase orders for replacement manuals to your local Cleaver-Brooks authorized representative.
Manual Part No. 750-363
08/2017 Printed in U.S.A.
Cleaver-Brooks 2017
CLEAVER-BROOKS
Model CFLC
ClearFire Packaged Boiler
Condensing Boiler
Operation and Maintenance Manual

iv
TO: Owners, Operators and/or Maintenance Personnel
This operating manual presents information that will help to properly operate and care for the equipment. Study its con-
tents carefully. The unit will provide good service and continued operation if proper operating and maintenance instruc-
tions are followed. No attempt should be made to operate the unit until the principles of operation and all of the
components are thoroughly understood. Failure to follow all applicable instructions and warnings may result in severe
personal injury or death.
It is the responsibility of the owner to train and advise not only his or her personnel, but the contractors' personnel who
are servicing, repairing or operating the equipment, in all safety aspects.
Cleaver-Brooks equipment is designed and engineered to give long life and excellent service on the job. The electrical
and mechanical devices supplied as part of the unit were chosen because of their known ability to perform; however,
proper operating techniques and maintenance procedures must be followed at all times. Although these components af-
ford a high degree of protection and safety, operation of equipment is not to be considered free from all dangers and
hazards inherent in handling and firing of fuel.
Any “automatic” features included in the design do not relieve the attendant of any responsibility. Such features merely
free him of certain repetitive chores and give him more time to devote to the proper upkeep of equipment.
It is solely the operator’s responsibility to properly operate and maintain the equipment. No amount of written instructions
can replace intelligent thinking and reasoning and this manual is not intended to relieve the operating personnel of the
responsibility for proper operation. On the other hand, a thorough understanding of this manual is required before at-
tempting to operate, maintain, service, or repair this equipment.
Because of state, local, or other applicable codes, there are a variety of electric controls and safety devices which vary
considerably from one boiler to another. This manual contains information designed to show how a basic burner operates.
Operating controls will normally function for long periods of time and we have found that some operators become lax in
their daily or monthly testing, assuming that normal operation will continue indefinitely. Malfunctions of controls lead to
uneconomical operation and damage and, in most cases, these conditions can be traced directly to carelessness and
deficiencies in testing and maintenance.
It is recommended that a boiler room log or record be maintained. Recording of daily, weekly, monthly and yearly main-
tenance activities and recording of any unusual operation will serve as a valuable guide to any necessary investigation.
Most instances of major boiler damage are the result of operation with low water. We cannot emphasize too strongly the
need for the operator to periodically check his low water controls and to follow good maintenance and testing practices.
Cross-connecting piping to low water devices must be internally inspected periodically to guard against any stoppages
which could obstruct the free flow of water to the low water devices. Float bowls of these controls must be inspected
frequently to check for the presence of foreign substances that would impede float ball movement.
The waterside condition of the pressure vessel is of extreme importance. Waterside surfaces should be inspected fre-
quently to check for the presence of any mud, sludge, scale or corrosion.
It is essential to obtain the services of a qualified water treating company or a water consultant to recommend the proper
boiler water treating practices.
The operation of this equipment by the owner and his or her operating personnel must comply with all requirements or
regulations of his insurance company and/or other authority having jurisdiction. In the event of any conflict or inconsis-
tency between such requirements and the warnings or instructions contained herein, please contact Cleaver-Brooks be-
fore proceeding.
DO NOT OPERATE, SERVICE, OR REPAIR THIS EQUIPMENT UNLESS YOU FULLY UNDERSTAND ALL
APPLICABLE SECTIONS OF THIS MANUAL.
DO NOTALLOW OTHERS TO OPERATE, SERVICE, OR REPAIR THIS EQUIPMENT UNLESS THEYFULLY
UNDERSTAND ALL APPLICABLE SECTIONS OF THIS MANUAL.
FAILURE TO FOLLOW ALL APPLICABLE WARNINGS AND INSTRUCTIONS MAY RESULT IN SEVERE
PERSONAL INJURY OR DEATH.
!DANGER
WARNING

v
TABLE OF CONTENTS
Section 1 Introduction
CFLC Features and Benefits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Standard Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Optional Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
Section 2 Installation
Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
Boiler Room . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Flue gas/combustion air . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Water Treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Boiler flush . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6
Using glycol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6
Gas connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Boiler water piping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14
Minimum boiler overpressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18
Condensate removal and treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18
Electrical Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-21
Wiring diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-23
Section 3 Stack and Intake Vent Sizing and Installation
Venting Connections - General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
Vertical Venting / Inside Combustion Air . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6
Vertical Venting / Direct Vent or Sealed Combustion Air . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7
Venting for Multiple Units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-8
Combustion Air / Boiler Room Ventilation Requirements. . . . . . . . . . . . . . . . . . . . . . . . . 3-10
Section 4 Commissioning
Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
Filling Boiler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
Control Setpoints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2
Model CFLC Boiler / Burner Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3
Falcon Display/Operator Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Controller Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7
Variable Speed Drive Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-9
Burner Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-10
Fan Speed Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-10
Initial Start-up Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-10
Post Start-up Checkout Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-17
Falcon Control Functions and Customer Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-18
Section 5 Service and Maintenance
Disassembly for Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2
Reassembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
Ignition and Flame Detection Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-6
Extended Shutdown . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
Emergency Shutdown. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-8
Section 6 Parts
Recommended Spare Parts List Model CFLC ...................................................................6-2
Boiler Mechanical Assembly........................................................................................... 6-3
Burner Assembly ......................................................................................................... 6-7
UV Scanner ................................................................................................................. 6-9
Gas Train .................................................................................................................. 6-10
Dual Fuel Gas Trains .................................................................................................. 6-18
Pilot Gas Train .......................................................................................................... 6-21
Control Panel ............................................................................................................ 6-22
Cables and Cable Harness .......................................................................................... 6-23
Optional Parts ........................................................................................................... 6-24
Casing & Insulation .....................................................................................................6-25
Appendix A - Falcon Parameters
Appendix B - VSD Parameters
Appendix C - Gas Valve
Appendix D - Falcon Alert, Hold, and Lockout Codes
Appendix E - Falcon Lead Lag
Appendix F - Falcon Program Module

vi

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Section 1
Introduction
CFLC Features and Benefits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Standard Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Optional Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7

Section 1 — Introduction
1-2 Part No. 750-363
1.1 CFLC FEATURES AND BENEFITS
Compact Firetube Design
The CFLC boiler is a two pass horizontally fired durable Firetube boiler. The extended heating surface tubes
provide for very high levels of performance in a compact space. The boiler is designed to fire natural gas.
High Efficiency
With the extended heating surface tubes the boiler can produce fuel to water efficiency of up to 99%
depending upon operating conditions.
Advanced Construction
Constructed to ASME standards, the CFLC Boiler will provide many years of trouble free service.
First pass tubes are made from SA178A Carbon Steel and are of rifle design for maximum heat transfer.
Second pass tubes are made from UNS S32101 Duplex Stainless Steel with AluFer extended heating
surface inserts for maximum heat transfer.
Dual Temperature Return
Two return pipes - high and low temperature - allow condensing performance with as little as 10% return
water at condensing temperature.
Ease of Maintenance
The steel enclosures are readily removable for access to all key components. A hinged burner provides
access for burner maintenance and fireside inspection.
Quality Construction
ASME construction ensures high quality design, safety, and reliability.
ISO 9001 certified manufacturing process ensures the highest degree of manufacturing standards is always
followed.
Full Modulation
The burner and combustion fan modulate to provide only the amount of heat required, providing quiet and
efficient operation under all conditions.
Premix Technology
The CFLC boiler utilizes "Premix" technology to mix both fuel and combustion air prior to entering the firing
chamber. This technology provides clean, efficient combustion with very low emission levels.
Designed For Heating Applications
The pressure vessel is constructed of durable ASTM Grade Steel and Stainless Steel materials to provide
many years of operating life.
Thermal shock resistant design with large water volume and low pressure drop is ideal for primary variable
flow applications.
1.2 STANDARD EQUIPMENT
1.2.1. The Boiler
The boiler is designed for a Maximum Allowable Working Pressure (MAWP) of 160 psig (11 Bar) in
accordance with the ASME Code for Low Pressure Section IV Hot Water Boilers and is stamped accordingly.
Operating pressure shall be less than 144 psig (9.9 Bar).
The vessel is mounted on a steel base with insulation & casing provided including trim and controls. Trim
and controls include safety relief valve, pressure and temperature gauges, probe type low water control, and
Falcon hydronic boiler control with associated sensors.

Section 1 — Introduction
Part No. 750-363 1-3
1.2.2. The Burner
The burner utilizes a premix venturi, self-regulating
fuel train, variable speed blower modulation, and
Fecralloy metal fiber burner head.
Modulating combustion air fan provides 5:1
turndown.
Combustion canister of the burner is constructed of a
Fecralloy-metal fiber for solid body radiation of the
burner flame, which provides low emissions.
At maximum firing rate, the sound level of the burner
is less than 85 dBA, measured in front of the boiler at
a distance of 3 feet.
Room air for combustion is standard (combustion air
filter provided).
A direct vent combustion air adapter kit is available.
Refer to Installation and Parts sections in this manual
for options and details.
1.2.3. Burner Gas Train
The gas train assembly is provided in accordance with UL
certification and complies with ASME CSD-1. The gas train
assembly is factory assembled and wired, consisting of the
following components:
A. Low Gas Pressure Switch - manual reset
B. High Gas Pressure Switch - manual reset
C. Single body, dual safety motorized shut-off valves
with POC and regulating actuator
D. Manual Shutoff Butterball Valve
E. Regulator (optional, based on gas supply pressure)
F. Test cocks
1.2.4. Controls
The Falcon hydronic control is an integrated burner
management and modulation control with a touch-screen
display/operator interface.
The controller is capable of the following functions:
• Two (2) heating loops with PID load control.
• Burner sequencing with safe start check, pre-purge, pilot
ignition, and post purge.
• Electronic ignition.
• Flame Supervision.
• Safety shutdown with time-stamped display of lockout
condition.
• Variable speed control of the combustion fan.
• Supervision of low and high gas pressure, air proving, stack
back pressure, high limit, and low water.
• First-out annunciator.
• Real-time data trending.
• (3) pump/auxiliary relay outputs.
• Modbus communication capability.
• Outdoor temperature reset.
• Remote firing rate or setpoint control
• Setback/time-of-day setpoint
• Lead/Lag for up to 8 boilers
CAPS
HAPS
VENTURI
BURNER CANISTER
BLOWER
ASSEMBLY
Figure 1-1 Burner Assembly
GAS INLET
TO VENTURI
A
B
C
E
E
F
Figure 1-2 Gas Train (8000 shown)
D

Section 1 — Introduction
1-4 Part No. 750-363
1.2.5. Variable Speed Drive
Modulating combustion air fan speed is controlled by a Variable
Speed Drive mounted inside the front casing below the Falcon control
panel.
1.2.6. Component/Connection Locations
Figure 1-5 shows the CFLC component orientation and heat flow
path. The return water connections are at the lower vessel and the
hot water outlet is at the top of the boiler.
Figure 1-6 shows the locations of the safety valve and air vent
connections. Figure 1-7 shows the location of the return water
temperature sensor.
The stack is connected on the right side of the boiler when facing the
front. The flue gas duct sizes may be reduced at the vent connection.
See also Section 3, Stack and Intake Vent Sizing and Installation.
Figure 1-3 Control panel interior
IGNITION TRANSFORMER
(FAR SIDE)
FALCON CONTROLLER, HYDRONIC
WATER LEVEL
CONTROL - LWCO
TRANSFORMER, 115v/25v
TRANSFORMER, 460/230/208V PRI, 115 V SECONDARY,
350VA, FUSED TOP
TERMINAL TRACK
FUSE, 9 AMP
Figure 1-4 VSD (cutaway view)

Section 1 — Introduction
Part No. 750-363 1-5
Figure 1-5 CFLC Cutaway
Figure 1-6 Boiler safety valve(s) & air vent
TO STACK
Air Vent (optional) LWCO probe holder
Safety Valve(s)
EX Tubes
Alufer Tubes
Control Panel
Gas Train
Burner
Assembly
Water
Return (2)
Water
circulation
Combustion
gas flow
Furnace
Flue/
condensate
collection
chamber
Condensate
drain
Water Outlet
Boiler Drain
LWCO PROBE
HOLDER
GATE VALVE
AUTO AIR VENT
(OPTIONAL)
SAFETY VALVE(S)

Section 1 — Introduction
1-6 Part No. 750-363
Figure 1-7 Return temperature sensor (rear casing & insulation not shown)
Figure 1-8 Stack Outlet, Water Outlet, and Combustion Air Inlet
STACK OUTLET
COMBUSTION AIR FILTER
WATER
OUTLET
OUTLET TEMP.
sensor well

Section 1 — Introduction
Part No. 750-363 1-7
1.3 OPTIONAL EQUIPMENT
Certain project-specific options may have been supplied with the boiler if these options were specified at
the time of order entry. In addition, some options may have been provided (by others) that are not part of
Cleaver-Brooks’ scope of supply. In either case, the Cleaver-Brooks authorized representative should be
consulted for project specifics.
These are the options that are available for the CFLC boiler from Cleaver-Brooks:
A. Condensate neutralization tank assembly - consists of neutralizing media, filter, and PVC
condensate holding tank. This assembly is further described in Chapter 2.
B. Direct vent combustion air adapter kit
C. Outdoor temperature sensor for outdoor reset, frost protection, and warm weather shutdown
D. Header temperature sensor for multiple boiler Lead/Lag operation
E. Alarm Horn for safety shutdown
F. Relays for output signal for burner on, fuel valve open
G. Stack Thermometer
H. Stack temperature limit-sensor
I. Auto air vent
J. Boiler drain valve
K. Gas pressure relief valve
L. Gas pressure gauge
M. Water isolation valves
N. Hydronic circulating pumps
O. Seismic anchoring provisions
For options not listed, consult your authorized CB representative.

Section 1 — Introduction
1-8 Part No. 750-363

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Section 2
Installation
Assembly . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
Boiler Room . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Flue gas / combustion air . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Water treatment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Boiler flush . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6
Using glycol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6
Gas connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-8
Boiler water piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14
Minimum boiler overpressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18
Condensate removal and treatment . . . . . . . . . . . . . . . . . . . . . . . . . 2-18
Electrical connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-21
Wiring diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-23
Provisions for combustion and ventilation air must
be in accordance with the National Fuel Gas
Code, ANSI Z223.1, or the CAN/CSA B149
Installation Codes, or applicable provisions of the
local building codes. Failure to follow this warning
could result in personal injury or death.
The boiler must be installed such that the gas
ignition system components are protected from
water (dripping, spraying, rain, etc.) during
appliance operation and sevice. Failure to follow
this warning could result in equipment failure.
Caution
The installation must conform to the require-
ments of the authority having jurisdiction, or in
the absence of such requirements, to the
National Fuel Gas Code, ANSI Z223.1 and/or
CAN/CSA B149 Installation Codes.
If an external electrical source is utilized, the boiler
when installed must be electrically bonded to
ground in accordance with the requirements of the
authority having jurisdiction, or in the absence of
such requirements with the National Electrical
Code ANSI/NFPA 70 and/or the Canadian
Electrical Code Part I CSA C22.1.
!Warning
!Warning !Warning

Section 2 — Installation
2-2 Part No. 750-363

Section 2 — Installation
Part No. 750-363 2-3
2.1 BOILER ASSEMBLY AND PLACEMENT
2.1.1 Packaging
The Cleaver-Brooks Model CFLC boiler is shipped fully assembled, ready for installation.
2.1.2 Lifting and moving the boiler
The Model CFLC boiler is lifted by means of the holes provided in the upper tube sheets. See rigging diagram
below.
Figure 2-1 CFLC Rigging
!Caution
In order to avoid damage to the unit, lifting or
moving the boiler should only be done by
experienced personnel suitably equipped for
moving heavy equipment.
Note: The boiler
should not be moved
by pushing, prying, or
pulling on any part of
the casing.

Section 2 — Installation
2-4 Part No. 750-363
2.1.3 Boiler placement
The boiler or boilers should be mounted in accordance with Figure 2-2 below. Required front, rear, and side
clearances are shown. Under special circumstances, reduced side clearance between boilers may be
feasible. Contact your C-B authorized representative for assistance.
NOTE
The boiler assemblies are intended for installation in accordance with the appropriate
standards of the National Fire Protection Association and the building code recommended
by the American Insurance Association. Local codes may differ. Installation should provide
clearances to unprotected combustible material not less than those indicated in the
following:
Clearances to adjacent combustible construction not less than 36 inches from control
panel front, 24 inches from sides, and 36 inches above and rear. The floor beneath these
units may be combustible. In all cases, the flue pipe shall not pass through any floor or
ceiling or any combustible wall or partition unless suitably guarded.
Figure 2-2 Clearance Required (inches)
Top Clearance = 36”

Section 2 — Installation
Part No. 750-363 2-5
2.2 BOILER ROOM
The boiler room must comply with all building codes and regulations. An adequate supply of combustion
air is required for safe operation. If the optional sealed combustion/direct vent kit is used, ventilation must
be provided to meet applicable regulations for air supply.
Note: For further details on sealed combustion/direct vent kits, see Section 3, Stack and Intake Vent Sizing
and Installation and Section 6, Parts.
Clean combustion air is required for optimum efficiency and boiler operation. Dust and airborne
contaminants will adversely effect burner performance. An air filter is included to keep airborne
contamination from the burner.
If using sealed combustion/direct venting, the air intake should be positioned to keep rain or snow from
entering the intake piping.
The boiler must be installed so that the gas ignition system components are protected from water (dripping,
spraying, etc.) during appliance operation and service.
2.3 FLUE GAS / COMBUSTION AIR
The flue gases from the Model CFLC boiler should be removed via a gas-tight, temperature and corrosion
resistant flue gas pipeline. Only flue gas systems approved and tested by the relevant region or province are
to be connected to the boiler. Refer to flue piping manufacturer for proper installation and sealing
instructions. See also Chapter 3 of this manual for combustion air and flue gas venting requirements.
2.4 WATER TREATMENT
Cleaver-Brooks ClearFire condensing boilers are suitable for heating systems without significant oxygenation
capacity. Systems with continuous oxygenation capacity due to unknown or unseen leaks must be equipped
with a system separation or pretreatment device. Closed loop hydronic systems should incorporate air
separation, dirt elimination, and air venting.
Clean, soft water is generally the best heating medium for filling and make-up water in systems utilizing the
Model CFLC. If the water available from the main system is not suitable for use, then demineralization and/
or treatment with inhibitors is necessary. Treated filling and make-up water must be checked at least once
a year or more frequently if so specified in the application guidelines from the inhibitor manufacturer.
Those parts of the boiler in contact with water are manufactured with both ferrous materials and corrosion-
resistant stainless steel. The chloride content of the heating water should not exceed 30 ppm and the pH
level should be between 8.3 to 10.5 after six weeks of operation.
To maintain the boiler's efficiency and prevent overheating of the heating surfaces, the values in Table 2-2
should not be exceeded. Water make-up during the lifetime of the boiler should not be greater than 3 times
the system volume. A water meter should be installed on the makeup line to monitor makeup water volume.
Should the system require flushing or cleaning after installation of the CFLC, take care that no particulate
matter reaches the boiler during the cleaning process.
Table 2-1. Boiler room environmental limits
Maximum temperature 122 deg F
Minimum temperature 32 deg F
Humidity 90% RH non condensing
!Warning
The boiler must not be installed on carpeting.

Section 2 — Installation
2-6 Part No. 750-363
Table 2-2 Model CFLC Water Chemistry Requirements
2.5 BOILER FLUSH
Cleaver-Brooks recommends cleaning in accordance with the recommendations of the boiler owner’s water treatment
company for each individual site. The boiler may be flushed with or without heat applied, as deemed appropriate by the
chemical treatment company. A traditional steam “Boil Out” is not required on Cleaver-Brooks hot water boilers.
Following are some general recommendations to help ensure long boiler life and efficient operation.
NOTE: these are recommendations only. The chemical treatment supplier should recommend a procedure based on
the site conditions and quality of water being used to fill the system.
If the entire system is being flushed THROUGH the boiler, weld slag and deposits from the piping system may settle in
the boiler. The boiler is typically a low velocity zone where these deposits tend to accumulate. The boiler should be
drained periodically during the flushing process to keep any deposit build up to a minimum. When the system flush is
complete, drain the boiler completely and open water side inspection ports for visual inspection. Any deposits should be
manually flushed out.
If the boiler is isolated during the system flush, or if this is an equipment replacement only where minimal amounts of
system piping have been replaced, there should be minimal manufacturing deposits inside the boiler and no boiler flush
is required.
To provide the longest life of the equipment it is recommended but not mandatory to chemically treat the boiler prior to
start-up. The owner’s water treatment company should determine needed course of action for each installation.
2.6 USING GLYCOL
The Model CFLC boiler may be operated with a solution of glycol and water. Where glycols are added, the
system must first be cleaned and flushed. Correct glycol selection and regular monitoring of the in-use
concentration and its stability is essential to ensure adequate, long-term freeze protection, including
protection from the effects of glycol-derived corrosion resulting from glycol degradation.
Note: Corrosion and sludge deposits in old systems must be removed
prior to installation of a new boiler.
Parameter Limit Means of control
Glycol 25-50% Glycol fill/mixing station
pH 8.3 - 10.5 Buffering agent
Nitrates 50 ppm Chemical additives
Sulfates 50 ppm
Chloride < 250 ppm
Oxygen < 0.1 ppm Air separator/eliminator
Specific Conductivity < 3500 mmho/cm
Total Hardness < 10 ppm Softener
Table 2-3 Model CFLC Water Temperature Data (Non-Glycol)
Minimum inlet temp. 33oF
Maximum operating supply set point temp. 230oF
Maximum design temp. 250oF
Minimum supply set point temperature 130oF
Max allowable Delta T 100oF