U.S. Boiler Company K2 FT Guide

106377-01 - 4/16
WARNING
If the information in this manual is not
followed exactly, a re or explosion may
result causing property damage, personal
injury or loss of life.
-
Do not store or use gasoline or other
ammable vapors and liquids in the
vicinity 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 re department.
-Installation and service must be
performed by a qualied installer,
service agency or the gas supplier.
AVERTISSEMENT
Assurez-vous de bien suivre les instructions
données dans cette notice pour réduire au
minimum le risque d'incendie ou d'explosion
ou pour éviter tout dommage matériel, toute
blessure ou la mort.
-Ne pas entreposer ni utiliser d'essence
ni d'autres vapeurs ou liquides inam-
mables dans le voisinage de cet appareil
ou de tout autre appareil.
- QUE FAIRE SI VOUS SENTEZ UNE
ODEUR DE GAZ:
• Ne pas tenter d'allumer d'appareils.
• Ne touchez à aucun interrupteur. Ne
pas vous servir des téléphones dans
le bâtiment où vous vous trouvez.
• Appelez immédiatement votre
fournisseur de gaz depuis un voisin.
Suivez les instructions du fournisseur.
• Si vous ne pouvez rejoindre le
fournisseur de gaz, appelez le service
des incendies.
-L'installation et I'entretien doivent
être assuréx par un installateur ou un
service d'entretien qualié ou par le
fournisseur de gaz.
USER'S INFORMATION MANUAL
CONDENSING HIGH EFFICIENCY
GAS - FIRED HOT WATER BOILER

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Important Product Safety Information
Refractory Ceramic Fiber Product
Warning:
The Repair Parts list designates parts that contain refractory ceramic fibers
(RCF). RCF has been classified as a possible human carcinogen. When
exposed to temperatures above 1805°F, such as during direct flame contact,
RCF changes into crystalline silica, a known carcinogen. When disturbed as a
result of servicing or repair, these substances become airborne and, if inhaled,
may be hazardous to your health.
AVOID Breathing Fiber Particulates and Dust
Precautionary Measures:
Do not remove or replace RCF parts or attempt any service or repair work
involving RCF without wearing the following protective gear:
1. A National Institute for Occupational Safety and Health (NIOSH)
approved respirator
2. Long sleeved, loose fitting clothing
3. Gloves
4. Eye Protection
•Take steps to assure adequate ventilation.
•Wash all exposed body areas gently with soap and water after contact.
•Wash work clothes separately from other laundry and rinse washing
machine after use to avoid contaminating other clothes.
•Discard used RCF components by sealing in an airtight plastic bag. RCF
and crystalline silica are not classified as hazardous wastes in the United
States and Canada.
First Aid Procedures:
•If contact with eyes: Flush with water for at least 15 minutes. Seek
immediate medical attention if irritation persists.
•If contact with skin: Wash affected area gently with soap and water.
Seek immediate medical attention if irritation persists.
•If breathing difficulty develops: Leave the area and move to a location
with clean fresh air. Seek immediate medical attention if breathing
difficulties persist.
•Ingestion: Do not induce vomiting. Drink plenty of water. Seek
immediate medical attention.

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The following terms are used throughout this manual to bring attention to the presence of hazards of various risk levels.
Basic Operation and Maintenance
DANGER
There are no user serviceable parts on this boiler. Attempts to service this boiler by someone other than a
qualied gas service technician could void the warranty, cause property damage, personal injury or loss of
life.
CAUTION
Should overheating occur or the gas supply fail to shut off, do not turn off or disconnect the electrical
supply to the pump. Instead, shut off the gas supply at a location external to the appliance.
En cas de surchauffe ou si I'admission de gaz ne peut étre coupée, ne pas couper ni débrancher
l'alimentation électrique de la pompe. Fermer plutôt le robinet d'admission de gaz à l'extérieur de I'appareil.
Do not use this boiler if any part has been under water. Immediately call a qualied service technician to
inspect the boiler and to replace any part of the control system and any gas control which has been under
water.
CAUTION
Like all central heating appliances, this boiler is equipped with safety devices, which could cause it to
shutdown, requiring service to restore normal operation. Where such a shutdown could result in damage
from low temperatures (such as frozen pipes), do not leave the heating system unattended during cold
weather unless alarms or other safeguards are in place to prevent damage.
DANGER
Indicates an imminently hazardous situation
which, if not avoided, will result in death, serious
injury or substantial property damage.
WARNING
Indicates a potentially hazardous situation
which, if not avoided, could result in death,
serious injury or substantial property damage.
CAUTION
Indicates a potentially hazardous situation
which, if not avoided, may result in moderate or
minor injury or property damage.
NOTICE
Indicates special instructions on installation,
operation, or maintenance which are important
but not related to personal injury hazards.

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A. General
1. This manual covers the proper care and use of
your Condensing High Efciency Gas Fired Boiler.
2. Instructions to safely operate and shut down
this boiler are shown in Figure 1 on page 6, as well
as on a label afxed to the boiler.
3. This boiler uses an electronic means built into
the ignition system to extinguish the burner in the
event that ames exit the combustion chamber. If
the boiler fails to re, call a qualied gas service
technician to diagnose and correct the problem.
4. This boiler is equipped with a safety feature which
will shut down the burner in the event that there
is a blockage in the vent system. In the event that
the boiler fails to function, and the boiler is vented
through an outside wall accessible from the ground,
inspect the vent terminal on the outside wall for a
blockage such as a bee’s nest or ice. If a blockage
is found, the burner should ignite approximately
30 seconds after the blockage is removed. If no
blockage is found, or if the terminal is inaccessible
from the ground, the problem must be diagnosed
and corrected by a qualied gas service technician.
WARNING
Asphyxiation Hazard. In the event that the
ignition system on this boiler does not permit
the boiler to re, there is either a problem with
the ignition system or a problem with the vent
system. Call a qualied gas service technician
to diagnose and correct the problem.
A shutdown of the burner due to the pressure
switch is an indication that there is a problem
with the vent system, such as a blockage. The
boiler pressure switch should only be reset
after a qualied gas service technician has
diagnosed and corrected the venting problem
that caused the pressure switch to open.
B. Maintenance
1. On a continuous basis:
• Keep the area around the boiler free from
combustible materials, gasoline, and other
ammable vapors and liquids.
• Keep the area around the combustion air inlet
terminal and the area around the boiler free
from contaminants, including all sources of
hydrocarbons such as bleaches, fabric softeners,
chemicals, sprays, cleaners, paint, paints, paint
removers, refrigerants, and cat boxes. Traces of
these chemicals can be drawing into the boiler,
causing severe corrosion damage to the boiler
and/or objectionable odors.
• Keep the boiler room ventilation openings open
and unobstructed.
• Do not expose the boiler to large amounts of dust
such as that generated by drywall construction or
woodworking.
2. On a monthly basis:
WARNING
If any of the below listed conditions is found,
follow instructions “TO TURN OFF GAS TO
APPLIANCE” in Figure 1 and contact a qualied
gas service technician to correct the problem
before placing the boiler back in service. Failure
to correct these conditions could result in
property damage, personal injury or loss of life.
• Inspect vent and combustion air intake terminals
for obstruction or damage due to impact or
excessive temperature.
• Inspect vent and combustion air exterior wall
penetrations to be sure they are weather tight.
• Inspect the vent and combustion air intake
system for obstructions, loose joints, condensate
leakage, sags in horizontal runs of pipe,
corrosion, or other deterioration.
• Inspect water and gas lines for leaks.
• Remove boiler front door and inspect for carbon
(soot) in the cabinet, condensate drain leaks or
blockage, or deterioration of the visible controls,
wiring, or sheet metal components. If any of
these are found, have a qualied gas service
technician service the boiler immediately.
• Inspect ame for true yellow tipping. Adjust
thermostat to highest setting to turn on boiler and
view ames through observation glass with front
door removed. On high re the ame should be
stable and mostly blue. No true yellow tipping
should be present, however intermittent ecks of
yellow and orange in the ame caused by dust in
air are normal. See Figure 2. If the burner ame
looks satisfactory, adjust thermostat to normal
setting and reinstall boiler front door. If yellow
tipping is observed, have a qualied gas service
technician service the boiler immediately.
3. On an annual basis: have a qualied gas service
technician perform a more detailed inspection
of the burner, heat exchanger, controls, and vent
system and provide maintenance as specied in the
Installation, Operating, and Service Instructions.

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C. Combi Domestic Hot Water and Space Heating Models
1) Once a month, recommend homeowner check the
faucet temperature using a glass thermometer.
2) Turn on faucet completely to hottest setting
available. Let faucet run for 3 minutes.
3) Measure faucet temperature using mercury free
glass thermometer that can be purchased at a local
hardware store.
4) Ensure steady state temperature is no more than
120°F (49°C).
5) Once a year, operate domestic water relief valve on
boiler several times up and down draining several
gallons of water through valve.
NOTICE
Hard water conditions may result in scale deposits in Combi components. Hard water will signicantly
shorten the life of these parts. Water conditioning is recommended for water hardness greater than
200 ppm.
DHW output capacity in GPM changes with varying domestic inlet water temperatures.
Do not use ethylene glycol or chemicals that are not explicitly permitted by the boiler installation
instructions. See the “Start-Up and Checkout” section of instructions for important information on
water chemistry requirements.
DANGER
Electrical Shock Hazard. Positively assure all electrical connections are unpowered before attempting
installation or service of electrical components or connections of the boiler or building. Lock out all
electrical boxes with padlock once power is turned off.
DANGER
Water temperature above 120°F (49°C) can cause serious injury. Mixing valve temperature setting should
be done by a licensed contractor per local code requirements. To ensure correct temperature control, use
the water thermometer at faucet outlet.

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Figure 1: Lighting Instructions
Operating Instructions

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Figure 2: Burner Flame
NOTICE
This boiler has a heat exchanger made from a
special stainless steel alloy which can be severely
damaged by frequent additions of water or by the
addition of boiler water additives which are not
designed for use with stainless steel boilers. If
it is necessary to add water to the boiler, have a
service technician check the system for leaks. Do
not add any chemicals to the boiler not listed in the
Installation, Operating and Service Instructions.
Warranty is void if the service and maintenance
procedure shown in the Installation, Operating
and Service Instructions is not followed.
WARNING
Carbon (“soot”) in or near the burner
compartment area is an indication of a potential
carbon monoxide hazard. If carbon is found,
immediately follow instructions "TO TURN OFF
GAS TO APPLIANCE" in Figure 1 and contact a
qualied gas service technician to correct the
problem before placing the boiler back in service.

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