Navien NFC-250/200H Guide

WARNING
If the information in these instructions is not followed exactly, a re or explosion may result,
causing property damage, personal injury, or death.
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.
The installation must conform with local codes or, in the absence of local codes, the National
Fuel Gas Code, ANSI Z223.1/NFPA 54 and/or CSA B149.1, Natural Gas and Propane Installation
Code.
+
NSF/ANSI 372
Keep this manual near this boiler for future reference
whenever maintenance or service is required.
* The wetted surface of this product contacted by consumable water
contains less than one quarter of one percent (0.25%) of lead by
weight.
User’s Information Manual
NFC-H Condensing Combi-Boilers
Model NFC-250/175H
NFC-250/200H
u
al near this boiler for future re
f
n
tenance or service is re
q
uired.

2Contents
Contents
1. Safety Information 3
2. About the Boiler 7
2.1 Description of the Boiler 7
2.2 Parts of the Boiler 7
2.3 The Front Panel 8
3. Operating the Boiler 10
3.1 Turning the Boiler On or Off 10
3.2 Adjusting the System Temperatures 10
3.3 Accessing Basic Menu Items 12
3.4 Resetting the Boiler 13
4. Maintaining the Boiler 14
4.1 Cleaning the Boiler 14
4.2 Draining the Boiler 14
4.3 Cleaning the Air Intake Filter 15
4.4 Protecting the Boiler from Freezing 17
4.5 Maintenance Schedules 18
5. Troubleshooting 23
5.1 Solving Basic Problems 23
5.2 Understanding Error Codes 24

3Safety Information
The following safety symbols are used in this
manual. Read and follow all safety instructions in
this manual precisely to avoid unsafe operating
conditions, fire, explosion, property damage,
personal injury, or death. Keep this manual for
future reference.
DANGER
Indicates an imminently hazardous situation
which, if not avoided, could result in severe
injury or death.
WARNING
Indicates a potentially hazardous situation
which, if not avoided, may result in injury or
death.
CAUTION
Indicates a potentially hazardous situation that,
if not avoided, could result in property damage.
DANGER
If you do not follow these instructions exactly,
a fire or explosion may result causing property
damage, personal injury or loss of life.
A. This appliance 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
appliance 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
ƔDo not try to light any appliance.
ƔDo not touch any electric switch; do not
use any phone in your building.
ƔImmediately call your gas supplier from
a neighbor’s phone. Follow the gas
supplier’s instructions.
ƔIf you cannot reach your gas supplier, call
the fire department.
ƔDo not return to your home until
authorized by your gas supplier or the
fire department.
C. Do not use this appliance if any part has
been under water. Immediately call a
qualified service technician to inspect the
appliance and to replace any part of the
control system and any gas control which
has been under water.
1. Safety Information

4 Safety Information
WARNING
Shut o the gas supply if the boiler is
damaged.
Have your installer or plumber show you
the location of the gas shut o valve and
demonstrate how to close the valve. If the
boiler is damaged as a result of overheating,
re, ood, or any other reason, close the
manual shut o valve and do not operate the
boiler again until it has been inspected by a
qualied technician.
Do not store or use gasoline or other
ammable liquids near this boiler.
Doing so may result in re or explosion.
Do not place combustibles, such as
newspapers or laundry, near the boiler or
venting system.
Doing so may result in a re.
Do not place or use hair sprays, spray
paints,or any othercompressedgasesnear
the boiler or venting system, including the
vent termination.
Doing so may result in re or explosion.
Do not operate the boiler with the front
cover opened.
Doing so may result in re or carbon
monoxide (CO) poisoning, which may result
in property damage, personal injury, or death.
Do not operate this boiler without proper
venting.
Doing so may result in re or carbon
monoxide (CO) poisoning, which may result
in property damage, personal injury, or death.
Inspect the vent termination and air intake
supply annually to ensure proper operation
of the boiler. Turn o and discontinue use
of the boiler if any of the vent pipes, vent
elbows, or intake pipes are damaged in any
way, separated at a joint, or show evidence of
corrosion, rusting, or melting.
WARNING
Do not touch the power cord or internal
components of the boiler with wet hands.
Doing so may result in electric shock.
Do not make any electrical connections
before turning o the electrical power
supply at service entrance panel.
Doing so may result in severe personal injury
or death.
California law requires the following Prop 65
warning to be provided:
WARNING
Cancer and Reproductive Harm -
www.P65Warnings.ca.gov

5Safety Information
DANGER
HOT
BURN
To prevent burns:
ƔUse the lowest operating temperature setting
necessary to provide comfortably-hot water.
ƔIf your household has children or elderly or
disabled residents, consider using a lower
temperature setting.
ƔDo not leave children, the elderly, or disabled
persons unsupervised.
ƔDo not allow small children to play
unsupervised in the bathroom.
ƔDo not allow anyone to change the water
temperature while hot water is running.
ƔRead all the instructions in this manual
carefully before changing the temperature
setting.
ƔFeel the water before using it on children, the
elderly, or the disabled.
ƔIf it is necessary to set the water temperature
above 125°F (52°C), consider installing a
thermostatically-controlled mixing valve
or temperature-limiting valve. Contact a
licensed plumber or your local plumbing
authority for more information.
CAUTION
ƔDo not attempt to repair or replace any
part of the boiler, unless it is specifically
recommended in this manual.
For all other service, contact an authorized
technician or licensed professional. Improper
adjustments, alterations, service, or
maintenance may lead to property damage,
personal injury, or death and will void your
warranty.
ƔDo not operate the boiler if you feel
something is wrong with it.
Doing so may result in product damage or
personal injury.
ƔDo not allow children to operate or access
the boiler.
Doing so may result in product damage or
personal injury.
ƔDo not turn on the boiler unless the water
and gas supplies are fully opened.
Doing so may damage the boiler.
ƔDo not use this boiler for anything other
than its intended purpose, as described in
this manual.
ƔDo not remove the front cover unless
the power to the boiler is turned off or
disconnected.
Failure to do so may result in electric shock.
ƔWhen servicing the controls, label all wires
prior to disconnecting them.
Failure to do so may result in wiring errors,
which can lead to improper or dangerous
operation.
ƔDo not use unapproved replacement or
accessory parts.
Doing so may result in improper or dangerous
operation and will void the manufacturer’s
warranty.
ƔDo not place anything in or around the vent
terminals, such as a clothes line, that could
obstruct the air flow in or out of the boiler.
ƔThis boiler has been approved for use in the
USA and Canada only.
Using the boiler in any other country will void
the manufacturer’s warranty.
ƔShould overheating occur or the gas supply
fail to shut off, turn off the manual gas
valve to the appliance.

6 Safety Information
DANGER
This boiler’s DHW temperature is set to 120°F
(49°C) at the factory for your safety and comfort.
Increasing the temperature increases the risk of
accidental scalding. Water temperatures at or
above 125°F (52°C) can cause instant scalding,
severe burns, or death. Before you decide
to change the temperature setting, read the
following charts carefully.
Water
Temperature
Time in which a young child can
suffer a full thickness
(3rd degree) burn
160°F (70°C) Less than 1 second
140°F (60°C) 1 second
130°F (55°C) 10 seconds
120°F (49°C) 10 minutes
100°F (37°C) very low scald risk

7About the Boiler
2.1 Description of the Boiler
The Navien NFC-H boiler is available in 2 models:
NFC-250/175H and NFC-250/200H.
The main features are as follows:
ƔPower Interruption: When the power is restored
after a power failure, the boiler will automatically
start and return to normal operation. A manual
reset is not required.
ƔFreeze Protection: A sensor inside the boiler
automatically detects the temperature and,
if necessary, initiates a safety heating cycle to
prevent internal equipment damage due to
freezing temperatures.
ƔShort-Circuit Protection: Any short-circuit
occurring in the boiler’s electrical circuit
immediately blows the internal glass fuses and
automatically cuts off the gas supply.
ƔLightning Protection: Each boiler is specially
grounded, both internally and externally, to
protect against lightning strikes.
ƔCarbon Monoxide Protection: The boiler is
designed to maintain a safe air-to-gas ratio and
combustion rate. This function is continuously
monitored by the boiler’s combustion controls.
ƔAuto Fan Detection: The rotation of the fan is
automatically detected and controlled. Fan failure
will stop the operation of the boiler.
ƔBoiling Prevention: Excessive temperatures will
automatically stop the boiler.
2.2 Parts of the Boiler
2.2.1 Front View
Exhaust
Gas Vent
Combustion
Air Intake
2.2.2 Bottom View
14.6”(370mm)
2.6”(67 mm)
9.7”(247 mm)
5.2”(131 mm)
AD E
17.3”(440mm)
8.5”(215 mm)
10.6“(269 mm)
3.3”
(85mm)
2”
(53mm)
B C FG
5.4”
(136.6mm)
5.4”
(136.6mm)
3.4”
(87mm)
# Description
A Heating Supply
B Hot Water Outlet (DHW)
C Cold Water Inlet (DHW)
D Auto Feeder Inlet (Make-up Water)
E Heating Return
F Gas Connection
G Condensate Outlet
2. About the Boiler

8 About the Boiler
2.3 The Front Panel
The front panel allows you to adjust the
temperature and view the operating status or error
codes. Remove the protective sheet from the front
panel before using it.
2.3.1 Icons and Digital Display
The icons and digital display on the front panel
provide important information required for the
boiler’s operation. Refer to the following table for
detailed information.
a
Outdoor reset
Displayed when the Outdoor
Reset feature is enabled.
b
Combustion
Displayed when the burner is
combusting.
c
System check or error
Displayed when an error is
detected or a system check is
needed due to service alarm
overtime.
d
Anti-freeze
Displayed when the boiler
is operating in anti-freeze
mode.
Auto air purge
Displayed when an auto air
purge is being performed.
e
Cascade/Main mode
Flashes when configuring a
cascade system. Turns on solid
if the boiler is set as the Main
unit in a cascade system.
f
DHW Operation
Displayed when the pre-
heating feature is activated.
ƔAlways on ( ), Intelligent
(), Weekly ( ),
Aquastat ( ), Manual ( )
AHU connection
Displayed when the AHU
connection settings are
enabled. If there is a problem
or a connection is being
made, this icon will blink.
g
DHW demand
Indicates that DHW
demand is present.
h
DHW temperature
Displays the set and current
DHW temperature.
i
System pressure
Displays the internal water
pressure of the boiler
system.
j
Outdoor temperature
Displays the outdoor
temperature.
k
Space heating
temperature
Displays the set and
current space heating
temperature.
l
Space heating demand
Indicates the space heating
demands from thermostats
1, 2, and 3.
b
a
d
f
c
l
k
j
g
h
i
e

9About the Boiler
2.3.2 Buttons and Command Dial
Using the buttons and the Command dial ( ) on
the front panel, you can turn on or off the boiler,
monitor the current operation status, and set the
values required for the boiler’s operation, such as
space heating and DHW supply temperatures. Refer
to the following table for detailed information.
a
Back button
Return to the previous menu
or screen.
bMode button
Enter the boiler’s main menu.
cPower button
Turn on or off the boiler. d
Command dial
Rotate to switch between
menu items, or to increase/
decrease values.
Press to make a selection or
to confirm changes.
c
b
d
a

10 Operating the Boiler
WARNING
Follow the instructions below to avoid unsafe
operating conditions that could cause property
damage, severe personal injury, or death.
ƔEnsure that the boiler is filled with water
before turning it on.
ƔIf overheating occurs or the gas supply fails to
shut off, shut off the gas supply to the boiler
by using the manual gas valve.
ƔIf any part of the boiler has been submerged
in water, do not use this appliance and
immediately call a qualified service
technician. The boiler must be replaced.
3.1 Turning the Boiler On or Off
To turn the boiler on or off, press the Power button
().
When the power is on, the boiler automatically
enters normal operation mode, and the boiler’s
operating conditions are displayed on the screen.
Note The boiler status icons remain displayed
when the boiler is turned off.
3.2 Adjusting the System
Temperatures
3.2.1 Adjusting the Space Heating
Temperature
To adjust the heating temperature:
1. In normal operation mode, rotate the Command
dial ( ) . The space heating temperature ( ) is
highlighted on the screen.
2. Press the Command dial ( ) to select the space
heating temperature. The highlighted section
will flash.
3. Rotate the Command dial ( ) to the right or
left to increase or decrease the temperature.
4. Press the Command dial ( ) to confirm the
new temperature.
3. Operating the Boiler

11Operating the Boiler
2. Rotate the Command dial ( ) to the right to
select the DHW temperature.
3. Press the Command dial ( ) to select the DHW
temperature ( ). The highlighted section will
flash.
4. Rotate the Command dial ( ) to the right or
left to increase or decrease the temperature.
5. Press the Command dial ( ) to confirm the
new temperature.
6. Press the Back button ( ) to return to normal
operation mode, or rotate the Command dial
() to adjust other operation conditions.
You can adjust the temperature while the display is
flashing. Once the display stops flashing, the current
temperature setting is stored.
Note ƔTake note of the original DHW
temperature in case you want to
restore it to the default.
ƔThe DHW temperature range is 86°F
(30°C) to 140°F (60°C) with 120°F as
the default setting.
ƔThe boiler will retain your settings
during a power outage.
5. Press the Back button ( ) to return to normal
operation mode, or rotate the Command dial
() to adjust other operation conditions.
You can adjust the temperature while the
highlighted section is flashing. Once the flashing
stops, the current temperature setting is stored.
Note ƔThe space heating temperature
cannot be adjusted when the Outdoor
Reset Control is used.
ƔIn case of outdoor reset sensor
malfunction, the boiler will operate at
this set temperature.
ƔTake note of the original heating
temperature in case you want to
restore it to the default.
ƔThe default space heating supply
water temperature range is 104°F
(40°C, Absolute MIN) to 180°F (82°C,
Absolute MAX).
ƔThe default space heating return
water temperature range is 86°F
(30°C, Absolute MIN) to 149°F (65°C,
Absolute MAX).
ƔYou can adjust the temperature ranges
in the parameter settings menu.
ƔThe boiler will retain your settings
during a power outage.
3.2.2 Adjusting the DHW Temperature
To adjust the water temperature:
1. In normal operation mode, rotate the Command
dial ( ). The space heating temperature ( ) is
highlighted on the screen.

12 Operating the Boiler
Item Description
5. AHU SH Set
Temp
Note
Use with iFlow Air
Handlers Only.
AHU Space Heating Set
Temperature (°F)
ƔIf AHU is not connected, “--”
will be displayed.
ƔThe temperature is
displayed by 1 degree
increments for Fahrenheit
and by 0.5 degree
increments for Celsius.
This is due to the degree
control specifications of
0.5 degree for the AHU
communication type.
6. Supply Temp Heating supply temperature
(°F)
7. Return Temp Boiler return temperature (°F)
8. Sys Supply Temp System supply temperature
(°F)
9. Sys Return Temp System return temperature
(°F)
10. Outlet 2 Temp Heat exchanger outlet
temperature (°F)
11. Outlet Temp Outlet temperature (°F)
12. Inlet Temp Inlet temperature (°F)
13. Outdoor Temp Outdoor temperature (°F)
14. Approx. Boiler
Flow SH flow rate (GPM)
15. DHW Flow DHW flow rate (GPM)
16. Water Pressure Water pressure (psi)
17. Flame Value
Flame detector AD value
ƔFlame On: 8bit AD values
equal to or lower than 70
ƔFlame Off: 8bit AD values
equal to or higher than 175
18. Fan Target RPM Set fan speed (RPM)
19. Fan Current
RPM Fan speed (RPM)
20. Fan Target APS Set APS voltage (V)
21. Fan Current
APS APS voltage (V)
3.3 Accessing Basic Menu Items
In the Main Menu screen, you can view the boiler’s
operating conditions, configure the space heating
and DHW temperatures, and review error history.
Press the Menu button ( ) to enter the Main Menu
screen.
To view information about the boiler, press the
Menu button ( ), and then select “1. Status
Information”.
Rotate the Command dial ( ) to switch between
the information items. Press the Command dial ( )
to select an item and view the information.
Press the Back button ( ) to exit information view
mode.
Item Description
1. Operation State Current Operation State
2. Heat Capacity Heat Capacity (%)
3. SH Set Temp Space heating set
temperature (°F)
4. DHW Set Temp DHW set temperature (°F)

13Operating the Boiler
3.4 Resetting the Boiler
If an error message appears during boiler operation,
reset the boiler to resolve the problem. Press the
Back button ( ) on the front panel to reset the
boiler.
If resetting the boiler does not solve the problem,
refer to the Troubleshooting section of this manual
or contact Technical Support at 1-800-519-8794.
Item Description
22. Flow control
valve status 100 - Close state
23. Mixing valve
status 0 - Close state
24. Exhaust Temp Exhaust temperature (°F)
25. Outdoor Reset Outdoor reset status (Enable
/ Disable)
26. Outdoor Reset
Curve
Outdoor reset curve load
type (displayed when the
outdoor reset option“25.
Outdoor Reset” is enabled)
1: Finned Tube Baseboard
2: FAN Coil
3: Cast Iron Baseboard
4: Low Mass Radiant
5: High Mass Radiant
6: Radiator
7: Custom (set by installer)
27. Boost Interval
Time Boost interval set time (min)
28. High Altitude
Sea Level (0 - 2,000 ft)
Level 1 (2,000 - 5,400 ft)
Level 2 (5,400 - 7,700 ft)
Level 3 (7,700 - 10,100 ft)
29. Well pump Well pump status
OFF - Unused, ON - Used
30. Model Model type
31. Gas Fuel type (NG/LPG)
32. Main F/W Ver Main firmware version
33. Panel F/W Ver Controller panel firmware
version

14 Maintaining the Boiler
4.1 Cleaning the Boiler
CAUTION
Make sure the boiler is turned off and the power
supply is disconnected before cleaning the
boiler. The boiler may remain hot for several
minutes after it is turned off. To prevent burns,
wait until the boiler has cooled down before
cleaning.
To clean the boiler, wipe the outside with a damp
cloth. Use a non-acidic, non-abrasive cleaner
to remove any surface stains. The front panel is
moisture resistant, but it is not waterproof. Keep it as
dry as possible.
4.2 Draining the Boiler
You will need to drain the boiler under certain
circumstances such as when the boiler is not used
for an extended period of time in order to prevent
freeze damage.
Refer to“2.2 Parts of the Boiler” on page 7 for
details about part locations.
To drain the boiler:
1. Place a bucket under the boiler to collect the
residual water inside the boiler.
2. Press the Power button ( ) on the front panel
to turn off the boiler.
3. Close the gas valve.
23(1
&/26(
2
3(1
&
/
26
(
23(1
&/26(
23(1
&/26(
Gas Valve
Open Closed
4. Close the water supply valve and the return
valves on the manifold system.
4. Maintaining the Boiler

15Maintaining the Boiler
4.3 Cleaning the Air Intake Filter
If the air intake filter becomes clogged by dust
or lint, the boiler will cease to operate and“Error
Code 110”will appear on the front panel display.
To properly maintain the boiler, clean the air
intake filter as needed or as part of the annual
maintenance.
To clean the air intake filter:
1. Press the Power button ( ) on the front panel
to turn off the boiler.
2. Disconnect the power supply to the boiler.
3. Unfasten the 4 latches (2 at the top and 2 at the
bottom) to remove the front cover.
5. Remove the drain cap on the manifold system
to drain the boiler.
Drain Cap Drain Cap
Note ƔPlace a bucket under the boiler
to gather water released from the
manifold system.
ƔDo not allow the pump to become
wet.

16 Maintaining the Boiler
6. Remove the filter from the plastic assembly.
Dust and rinse it with clean running water.
7. Allow the filter to dry completely.
8. Place the filter assembly back into the boiler and
secure it with the screw.
9. Replace the front cover.
10. Reconnect the power supply to the boiler.
11. Press the Power button ( ) on the front panel
to turn on the boiler.
4. Remove the screw that secures the air intake
filter (the filter is located at the top left of the
boiler).
5. Pull the filter out of the boiler.

17Maintaining the Boiler
To ensure that the boiler does not freeze, follow
these guidelines:
ƔDo not unplug the power supply cord, except
for routine maintenance. The boiler has a freeze
protection function that requires power. The
freeze protection function will operate regardless
of whether or not the power is turned on or in
standby mode, as long as the power supply is still
connected.
ƔDo not close the gas valve, except for routine
maintenance, as this will limit additional freeze
protection.
ƔIf the boiler will not be used for an extended
period, drain the boiler.
If the power or gas supplies must be
disconnected for an extended period, drain the
boiler. Freezing damage may occur if there is
water remained in the boiler in cold weather.
Note ƔIf hot water will not flow and you
suspect that the boiler is frozen,
contact an authorized technician or
licensed professional.
ƔThis boiler requires very little
maintenance, however a qualified
technician should inspect the boiler at
the beginning of every heating season
and/or when there is a problem.
4.4 Protecting the Boiler from
Freezing
CAUTION
Damage due to freezing is not covered by the
Navien limited warranty.
ƔFreezing damage is most likely to occur due
to back drafting caused by negative pressure
in the building. This is not a manufacturing
defect, and therefore, Navien will not
warrant any damages due to freezing. The
installer is responsible for ensuring that
there is sufficient make-up air to avoid such
a situation and the owner is responsible for
ensuring that protection against freezing is
maintained.
ƔTo avoid freezing issues, we strongly
recommend the use of a direct vent exhaust
and intake system. Your installer should
ensure that the exhaust vent pipe and the
air intake pipe are both connected directly
from the collars on the top of the boiler to the
outdoors. This type of vent system minimizes
air movement within the boiler.
ƔThis boiler has an optional recirculation mode
that is used for freeze protection. This mode
should prevent the boiler from freezing, even
if the intake air duct is not vented directly.
ƔThe boiler is designed for indoor installation
only.

18 Maintaining the Boiler
Service technician (See the following instructions)
Annual
Start-up
General:
ƔAddress reported problems.
ƔInspect interior; clean and vacuum
if necessary.
ƔClean condensate trap and fill with
fresh water.
ƔCheck for leaks (water, gas, flue,
condensate).
ƔVerify flue and air lines in good
condition and sealed tight.
ƔCheck system water pressure/
system piping/expansion tank.
ƔCheck control settings.
ƔCheck ignition and flame rod (clean
and reposition).
ƔCheck wiring and connections.
ƔInspect flame (stable, uniform).
ƔInspect flame signal.
If combustion or performance indicate
need:
ƔFlush heat exchanger.
ƔRemove and clean air intake filter.
ƔRemove and clean space heating
strainer.
ƔRemove and clean inlet water filter.
WARNING
ƔFollow the service and maintenance
procedures given throughout this manual
and in component literature shipped with
the boiler. Failure to perform the service and
maintenance could result in damage to the
boiler or system.
ƔFailure to follow the directions in this manual
and component literature could result in
severe personal injury, death, or substantial
property damage.
ƔThe boiler should be inspected annually only
by a qualified service technician. In addition,
the maintenance and care of the boiler must
be performed to assure maximum boiler
efficiency and reliability. Failure to service and
maintain the boiler and system could result in
equipment failure.
ƔElectrical shock hazard – Turn off power to
the boiler before any service operation on
the boiler except as noted otherwise in this
instruction manual. Failure to turn off electrical
power could result in electrical shock, causing
severe personal injury or death.
4.5 Maintenance Schedules
Owner maintenance
Daily
ƔCheck the boiler area is free
of combustible/flammable
materials and air contaminants.
ƔCheck the pressure/
temperature gauge for signs of
higher than normal pressure.
Monthly
ƔVisually inspect the vent
piping for signs of leakage and
blockage.
ƔVisually inspect the burner
flames.
ƔInspect the condensate trap
and the PVC fittings.
Periodically ƔTest the LWCO for proper
operation.
Every 6
months
ƔInspect boiler piping (gas and
water) for leaks.
ƔTest to make sure the relief
valve is operating normally.
Non-heating
season
ƔShut boiler down (unless boiler
is used for domestic hot water).

19Maintaining the Boiler
Checking the Flue Vent System and Air
Piping
1. Visually inspect the entire flue gas venting
system and air piping for blockage,
deterioration or leakage. Repair any joints that
show signs of leakage. Verify that air inlet pipe is
connected and properly sealed (if installed).
2. Verify that boiler vent discharge and air intake
are clean and free of obstructions.
WARNING
Failure to inspect for the above conditions and
have them repaired can result in severe personal
injury or death.
Checking the Water System
1. Verify all system components are correctly
installed and operational.
2. Check the cold fill pressure for the system. Verify
it is correct (must be a minimum of 6 psi).
3. Watch the system pressure as the boiler heats
up (during testing) to ensure pressure does not
rise too high.
Note ƔIf the system contains glycol,
test for proper concentration as
recommended by manufacturer.
ƔExcessive pressure rise indicates
expansion tank sizing or performance
problem.
4. Inspect automatic air vents and air separators.
Remove air vent caps and briefly press push
valve to flush vent.
5. Replace caps. Make sure vents do not leak.
Replace any leaking vents.
Addressing the Reported Problems
Inspect any problems reported by the owner and
correct before proceeding.
Inspecting the Installation Area
1. Verify that boiler area is free of any combustible
materials, gasoline and other flammable vapors
and liquids.
2. Verify that air intake area is free of any of the
contaminants listed in Installation & Operation
Manual. If any of these are present in the boiler
intake air vicinity, they must be removed. If they
cannot be removed, reinstall the air and vent
lines per the Installation and Operation Manual.
Inspecting the Boiler Interior
1. Remove the front cover and inspect the interior
of the boiler.
2. Vacuum any sediment from inside the boiler
and components. Remove any obstructions.
Cleaning the Condensate Trap
1. Inspect the condensate drain line, condensate
fittings, and condensate trap.
2. Remove any sediment in the trap.
3. Fill with fresh water until the water begins to
pour out of the drain.
Checking all Piping for Leaks
Eliminate all system or boiler leaks. Continual fresh
makeup water will reduce boiler life. Minerals
can build up in sections, reducing heat transfer,
overheating heat exchanger, and causing heat
exchanger failure. Leaking water may also cause
severe property damage.
1. Inspect all water and gas piping and verify to be
leak free.
2. Look for signs of leaking lines and correct any
problems found.

20 Maintaining the Boiler
WARNING
ƔCertain naturally occurring conditions may
corrode the valve or its components over
time, rendering the valve inoperative. Such
conditions are not detectable unless the
valve and its components are physically
removed and inspected. This inspection
must only be conducted by a plumbing
contractor or authorized inspection agency
– not by the owner. Failure to re-inspect the
boiler relief valve as directed could result in
unsafe pressure buildup, which can result in
severe personal injury, death, or substantial
property damage.
ƔFollowing installation, the valve lever must
be operated at least once a year to ensure
that waterways are clear. Certain naturally
occurring mineral deposits may adhere to
the valve, rendering it inoperative. When
manually operating the lever, water will
discharge and precautions must be taken to
avoid contact with hot water and to avoid
water damage.
ƔBefore operating lever, check to see that
a discharge line is connected to this valve
directing the flow of hot water from the
valve to a proper place of disposal. Otherwise
severe personal injury may result. If no
water flows, valve is inoperative. Shut down
the boiler until a new relief valve has been
installed.
2. After following the above warning directions, if
the relief valve weeps or will not seat properly,
replace the relief valve. Ensure that the reason
for relief valve weeping is the valve and not
over-pressurization of the system due to
expansion tank waterlogging or undersizing.
Checking Expansion Tank
ƔExpansion tanks provide space for water to move
in and out as the heating system water expands
due to temperature increase or contracts as the
water cools.
ƔPerform annual checks as recommended by
manufacturer to ensure proper operation.
Checking the Pressure Relief Valves
1. Inspect the relief valve and lift the lever to verify
flow. Before operating any relief valve, ensure
that it is piped with its discharge in a safe area to
avoid severe scald potential.
Note Safety relief valves should be inspected
at least once every three years, by
a licensed plumbing contractor or
authorized inspection agency, to ensure
that the product has not been affected
by corrosive water conditions and to
ensure that the valve and discharge line
have not been altered or tampered with
illegally.