Navien NCB-180 Guide

Version: 1.00(Oct. 02. 2013)
Navien America, Inc.
20 Goodyear lrvine, CA 92618 TEL [phone] FAX [phone] www.navienamerica.com
Getting Service
If your boiler requires service, you have several options for getting service:
●Contact Technical Support at 1-800-519-8794 or on the website: www.navienamerica.com.
For warranty service, always contact Technical Support first.
●Contact the technician or professional who installed your boiler.
●Contact a licensed professional for the affected system (for example, a plumber or electrician).
When you contact Technical Support, please have the following information at hand:
●Model number
●Serial number
●Date purchased
●Installation location and type
●Error code, if any appears on the front panel display.
Combination Boiler
User’s Information
Manual

* Lead Free
H
Model
NCB-180 / 210 / 240
User’s
Information
Manual
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.
Combination Boiler
WARNING
If the information in these instructions is not followed exactly, a fire or explosion may result, causing
property damage, personal injury or death.
– Do not store or use gasoline or other flammable 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 fire department.
– Installation and service must be performed by a qualified installer, service agency or the gas
supplier.

2 Contents
Contents
1. Safety Information 3
2. About the Boiler 6
2.1 Description of the Boiler 6
2.2 Parts of the Boiler 6
2.3 The Front Panel 7
3. Operating the Boiler 9
3.1 Turning the Boiler On or Off 9
3.2 Adjusting the Temperature 9
3.3 Viewing Basic Information 10
3.4 Resetting the Boiler 11
4. Maintaining the Boiler 12
4.1 Cleaning the Boiler 12
4.2 Draining the Boiler 12
4.3 Cleaning the Inlet Water Filter (DHW side) 13
4.4 Cleaning the Strainer (Space Heating side) 14
4.5 Cleaning the Air Intake Filter 14
4.6 Protecting the Boiler from Freezing 16
4.7 Maintenance Schedules 17
5. Troubleshooting 21
5.1 Solving Basic Problems 21
5.2 Understanding Error Codes 22

Safety Information 3
WARNING
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
●Do not try to light any appliance.
●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.
●Do not return to your home until authorized by your
gas supplier or the fire department.
C. Use only your hand to push in or turn the gas control knob.
Never use tools. If the knob will not push in or 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 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.
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 potential 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.
1. Safety Information

4 Safety Information
DANGER
This boiler’s water 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
DANGER
HOT
BURN
To prevent burns:
●Use the lowest operating temperature setting necessary to
provide comfortably-hot water.
●If your household has children or elderly or disabled
residents, consider using a lower temperature setting.
●Read all the instructions in this manual carefully before
changing the temperature setting.
●Feel the water before using it on children, the elderly, or the
disabled.
●If 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.

Safety Information 5
CAUTION
●Do 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.
●Do not operate the boiler if you feel something is wrong
with it.
Doing so may result in product damage or personal injury.
●Do not allow children to operate or access the boiler.
Doing so may result in product damage or personal injury.
●Do not attempt to change the DHW water temperature
while the boiler is being used.
Doing so may result in personal injury.
●Do not turn on the boiler unless the water and gas
supplies are fully opened.
Doing so may damage the boiler.
●Do not turn on the water if the cold water supply shut-
off valve is closed.
Doing so may damage the boiler.
●Do not use this boiler for anything other than its
intended purpose, as described in this manual.
●Do 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.
●When 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.
●Do not use unapproved replacement or accessory parts.
Doing so may result in improper or dangerous operation
and will void the manufacturer’s warranty.
●Do 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.
●This 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.
●Should overheating occur or the gas supply fail to shut
off, turn off the manual gas valve to the appliance.
WARNING
●Shut off the gas supply if the boiler is damaged.
Have your installer or plumber show you the location of the
gas shut off valve and demonstrate how to close the valve.
If the boiler is damaged as a result of overheating, fire, flood,
or any other reason, close the manual shut off valve and do
not operate the boiler again until it has been inspected by a
qualified technician.
●Do not store or use gasoline or other flammable liquids
near this boiler.
Doing so may result in fire or explosion.
●Do not place combustibles, such as newspapers or
laundry, near the boiler or venting system.
Doing so may result in a fire.
●Do not place or use hair sprays, spray paints, or any other
compressed gases near the boiler or venting system,
including the vent termination.
Doing so may result in fire or explosion.
●Do not operate the boiler with the front cover opened.
Doing so may result in fire 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 fire 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 off 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.
●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
off the electrical power supply at service entrance panel.
Doing so may result in severe personal injury or death.

6 About the Boiler
2.2 Parts of the Boiler
Front View
Exhaust
Gas Vent
Combustion
Air Intake
Bottom View
#Description
aPump Drain Plug
bSpace Heating Strainer
cSpace Heating Supply Connection
dSpace Heating Return Connection
eDHW Hot Water Outlet Connection
fGas Connection
gCold Water Inlet Filter
hCondensate Water Outlet
iAuto Feeder Connection
jCold Water Inlet Connection
2.1 Description of the Boiler
The Navien NCB boiler is available in 3 models: NCB-180, NCB-210,
and NCB-240.
The main features are as follows:
●Power 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.
●Automatic Water Fill: Should the water level in the system fall too
low, a sensor will automatically activate the refill circuit.
●Freeze Protection: A sensor inside the boiler automatically
detects the temperature and, if necessary, initiate a safety
heating cycle to prevent internal equipment damage due to
freezing temperatures.
●Short-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.
●Lightning Protection: Each boiler is specially grounded, both
internally and externally, to protect against lightning strikes.
●Carbon 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 air ratio control module.
●Thermostat Control Failure: Should the thermostat fail to
function properly, the boiler’s gas supply will be shut off
automatically as a safeguard.
●Auto Fan Detection: The rotation of the fan is automatically
detected and controlled. Fan failure will stop the operation of
the boiler.
●Boiling Prevention: Excessive temperatures will automatically
stop the boiler.
2. About the Boiler
a
b
c
d
e
f
g
h
i
j

About the Boiler 7
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.
b
a
f
g
h
c
d
e
i
j
psi
O/R
CONDENSING COMBI BOILER NCB
R
S
MODE
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
Space heating mode
f
S
Supply water control
Indicates space heating mode operation. Indicates supply water control status.
b
Error
g
R
Return water control
A code will appear on the display. Indicates return water control status.
c
Combusting
h
O/R
Outdoor Reset
Indicates burner operation. Indicates outdoor reset operation.
d
DHW mode
i
GPM
Indicates DHW mode operation. Indicates water flow.
e
Digital Display
j
psi
Psi
Indicates water pressure.

8 About the Boiler
k
l
m
n
o
p
psi
O/R
CONDENSING COMBI BOILER NCB
MODE
R
S
2.3.2 Buttons
Using the buttons 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.
k
Diagnostics button
n
Up button
For installers only Increases the temperature.
l
MODE
Mode button
O
Down button
Changes the mode. Decreases the temperature.
m
Reset button
p
Power button
Resets the boiler (When an error occurs). Turns the boiler on or off.

Operating the Boiler 9
2. Press the + (Up) or – (Down) buttons until the desired
temperature appears on the display.
MODE
You can adjust the temperature while the display is flashing. Once
the display stops flashing, the temperature setting is stored.
Note ●Take note of the original heating temperature in
case you want to restore it to the default.
●The default space heating supply water
temperature range is 104°F (40°C, Absolute MIN) to
180°F (82°C, Absolute MAX).
●The default space heating return water
temperature range is 86°F (30°C, Absolute MIN) to
149°F (65°C, Absolute MAX).
●You can adjust the temperature range in the
parameter settings menu.
●The boiler will retain your settings during a power
outage.
3.1 Turning the Boiler On or Off
To turn the boiler on or off, press the Power button for 0.3 seconds.
MODE
When the power is on, the water temperature of the space heating
supply will appear with the water pressure on the front panel
display in 5 second intervals.
Note ●If the Air purge is operating,“Air” will appear with
the water pressure on the front panel display in
5 second intervals.
●When displaying the water temperature of the
space heating supply, the supply or return water
icon flashes, depending on the space heating
control mode.
3.2 Adjusting the Temperature
3.2.1 Adjusting the Space Heating Temperature
To adjust the heating temperature:
1. Press the Mode button once. The space heating icon turns on.
MODE
3. Operating the Boiler

10 Operating the Boiler
3.3 Viewing Basic Information
To view information about the boiler, press the Mode button three
times.“INFO” will appear on the display.
MODE
Press the + or – buttons to switch between the information types.
Display Description
psi
O/R
SR
Space heating supply water
temperature (°F)
psi
O/R
SR
Space heating return water
temperature (°F)
psi
O/R
SR
Domestic hot water outlet
temperature (°F)
psi
O/R
SR
Cold water inlet temperature (°F)
psi
O/R
SR
Domestic Hot Water (DHW) Flow
rate in GPM
psi
O/R
SR
Outdoor air temperature (°F)
(with optional Outdoor Temperature
Sensor only)
3.2.2 Adjusting the DHW Water Temperature
WARNING
Before adjusting the water temperature, read “To prevent
burns:” on page 4 carefully. Water above 120°F can cause
instant scalding, severe burns, or death.
To adjust the water temperature:
1. Make sure that all hot water faucets are closed, and ensure that
the internal circulator and any external circulating pumps are
off.
2. Press the Mode button twice. The DHW mode icon turns on.
3. Press + (Up) or – (Down) buttons until the desired temperature
appears on the display.
MODE
You can adjust the temperature while the display is flashing. Once
the display stops flashing, the temperature setting is stored.
Temperature range Adjusting the water
temperature
86-120°F (Fahrenheit mode)
30-50 °C (Celsius mode) 1°F or 1°C increments
120-140°F (Fahrenheit mode)
50-60 °C (Celsius mode)
Press for 2 seconds to adjust in
5°F or 2°C increments
Note The boiler will retain your settings during a power
outage.

Operating the Boiler 11
3.4 Resetting the Boiler
If an error message appears, you can try resetting the boiler to
resolve the problem. To reset the boiler, press the Reset button.
MODE
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.
Display Description
psi
O/R
SR
Outdoor reset curve
-: Not in use.
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)
psi
O/R
SR
Boost interval time (set by installer)
psi
O/R
SR
Space heating water pressure in PSI
To exit the Information mode, press the Reset button.

12 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 either both the space heating side
and domestic hot water (DHW) side, or one side only before
performing maintenance tasks, such as cleaning the inlet water
filter, or to prevent the boiler from freezing when it will not be used
for an extended period.
Refer to the“2.2 Parts of the Boiler” on page 6 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.
MODE
3. Close the gas valve.
Gas Valve Opened Closed
4. Close the water supply valve on the inlet to the boiler. If there
is no valve, turn off the water supply at the water main.
4. Maintaining the Boiler

Maintaining the Boiler 13
4.3 Cleaning the Inlet Water Filter (DHW
side)
To clean the filter:
1. Drain the DHW side of the boiler. Refer to “4.2 Draining the
Boiler” on page 12.
2. While the filter is removed, rinse it with clean running water
(cold) and, if necessary, scrub it clean with a brush.
3. Reinsert and tighten the filter.
4. Fill the boiler and check for proper operation.
5. Close off any heating zones that do not require draining and
open a purge valve to drain the space heating side. Open all
domestic hot water faucets completely to drain the water
heating side. The water that remains in the plumbing lines will
drain out.
Pump Drain Plug
Cold Water
Inlet Filter
Strainer
6. Remove the strainer from the bottom of the boiler.
7. Open the pump drain plug.
8. Remove the cold water inlet filter.
9. Allow the residual water to drain from the boiler.
10. When the water is completely drained, reinsert the cold water
inlet filter and close the pump drain plug.
11. To refill the boiler follow the steps of “Draining the Boiler” in
reverse.

14 Maintaining the Boiler
4.4 Cleaning the Strainer (Space Heating
side)
If the heating performance is decreased, you can increase the
heating performance by filtering impurities from the system.
To clean the strainer:
1. Drain the space heating side of the boiler. Refer to“4.2
Draining the Boiler”on page 12.
2. Remove the clip and then remove the strainer.
3. While the strainer is removed, rinse it with clean running water
(cold).
4. Reinsert and tighten the strainer.
5. Fill the boiler and check for proper operation.
4.5 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, you should clean the
air intake filter every 3-4 months.
To clean the air intake filter:
1. Press the Power button on the front panel to turn off the boiler.
MODE
2. Disconnect the power supply to the boiler.
3. Remove the front cover of the boiler.

Maintaining the Boiler 15
7. Allow the filter to dry completely.
8. Reinsert the filter into the plastic assembly.
9. Place the filter assembly back into the boiler and secure it with
the screw.
10. Replace the front cover.
11. Reconnect the power supply to the boiler.
12. 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.
6. Remove the filter from the plastic assembly and clean it with a
toothbrush and clean running water.

16 Maintaining the Boiler
If hot water will not flow and you suspect that the boiler is frozen,
follow these steps:
1. Press the Power button on the front panel to turn off the boiler.
2. Close the gas valve.
Gas Valve Opened Closed
3. Open the hot water faucet that is closest to the boiler.
4. Use a hair dryer or a portable electric heater to heat up both
the primary and secondary Heat Exchangers.
5. Check every few minutes to see if water is running at the open
faucet.
6. When the water starts flowing again, check the boiler and
piping for leaks. If you detect any leaks or the boiler is not
operating properly, contact an authorized technician or
licensed professional.
Note This 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.
4.6 Protecting the Boiler from Freezing
CAUTION
Damage due to freezing is not covered by the Navien limited
warranty.
●Freezing 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.
●To 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.
●This 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.
●The boiler is designed for indoor installation only.
To ensure that the boiler does not freeze, follow these guidelines:
●Do not unplug the power supply cord, except for routine
maintenance. The boiler has a freeze protection function that
requires electricity. The freeze protection function will operate
regardless of whether or not the power is turned on or off, as
long as the electric supply is still connected.
●Do not close the gas valve, except for routine maintenance, as
this will limit additional freeze protection.
●If 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.

Maintaining the Boiler 17
4.7 Maintenance Schedules
Owner maintenance
Daily ●Check boiler area
●Check pressure / temperature gauge
Monthly
●Check vent piping
●Check air piping (if installed)
●Check air and vent termination screens
●Check relief valve
●Check condensate drain
●Check air vents
Periodically ●Test low water cutoff (if used)
●Reset button (low water cutoff)
Every 6 months
●Check boiler piping (gas and water) for
leaks
●Operate relief valve
End of season
months
●Shut boiler down (unless boiler used for
domestic hot water)
Service technician (See the following instructions)
Annual Start-up
General:
●Address reported problems
●Inspect interior; clean and vacuum if
necessary
●Clean condensate trap and fill with
fresh water
●Check for leaks (water, gas, flue,
condensate)
●Verify flue and air lines in good
condition and sealed tight
●Check system water pressure/system
piping/expansion tank
●Check control settings
●Check ignition and flame rod (clean and
reposition)
●Check wiring and connections
●Flame inspection (stable, uniform)
●Flame signal
If combustion or performance indicate
need:
●Flush heat exchanger
●Remove and clean air intake filter.
●Remove and clean space heating
strainer.
●Remove and clean inlet water filter.
WARNING
●Follow 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.
●Failure to follow the directions in this manual and
component literature could result in severe personal injury,
death, or substantial property damage.
●The 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.
●Electrical 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.
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.

18 Maintaining the Boiler
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.
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 12 psi).
3. Watch the system pressure as the boiler heats up (during
testing) to ensure pressure does not rise too high.
Note ●If the system contains glycol, test for proper
concentration as recommended by manufacturer.
●Excessive 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.
Checking Expansion Tank
●Expansion 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.
●Perform 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 re-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.
WARNING
Certain 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.

Maintaining the Boiler 19
WARNING
Following 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.
Before 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.
Inspecting the Ignition and Flame Detector Electrodes
1. Remove the ignition and flame detector electrodes from the
boiler heat exchanger.
2. Remove any deposits accumulated on the ignition/flame
detector electrode. If the electrodes cannot be cleaned
satisfactorily, replace with new ones.
3. Replace ignition/flame detector electrode, making sure gasket
is in good condition and correctly positioned.
Checking the Ignition Ground Wiring
1. Check that the ground wire is in good condition and securely
attached to the boiler casing.
2. Check ground continuity of wiring using continuity meter.
3. Replace ground wires if ground continuity is not satisfactory.
Checking all Boiler Wiring
●Inspect all boiler wiring, making sure wires are in good condition
and securely attached.
Checking the Control Settings
1. From the front panel, enter the Diagnostics Mode and check all
settings. Adjust settings if necessary.
2. Check settings of external limit controls (if any) and adjust if
necessary.
Performing Start-up and Checks
1. Start boiler and make sure that the boiler is operating properly.
2. Verify cold fill pressure is correct and that operating pressure
does not go too high.
Check the Burner Flame
1. Inspect flame through observation window.
2. If the flame is unsatisfactory at either high fire or low fire, check
for obstructions in the venting and ensure that the air intake
filter is clean.
Review with the Owner
1. Review the User’s Information Manual with the owner.
2. Emphasize the need to perform the maintenance schedule.
3. Remind the owner of the need to call a licensed contractor
should the boiler or system exhibit any unusual behavior.
4. Remind the owner to follow the proper shutdown procedure
and to schedule an annual start-up at the beginning of the
next heating season.