Toyotomi Oil Miser OM-148 (Type D) Troubleshooting guide

Instantaneous Oil-Fired Water Heater
Operation and Maintenance Instructions
MODEL OM-148
(Type D)
CONTENTS
IMPORTANT
READ AND UNDERSTAND INSTRUCTIONS BEFORE INSTALLING OR USING THIS WATER HEATER.
RETAIN INSTRUCTIONS FOR FUTURE REFERENCE. CHECK LOCAL CODES AND ORDINANCES FOR
PERMITTED USE.
CAUTION
THIS WATER HEATER SHALL NOT BE USED FOR COMMERCIAL USE OR FOR ANY PURPOSES OTHER
THAN HOT WATER SUPPLY USES. OTHER USAGE MAY CAUSE A MALFUNCTION OR SHORTEN ITS
SERVICE LIFE. DO NOT REMOVE THE RATING PLATE AND LABELS FROM THE WATER HEATER UNIT.
SECTION A:
Safety Tips ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 1
Safety Features ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 3
SECTION B:
Specifications⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 4
Dimensional Outline⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 5
Control Panel ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 6
Construction ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 6
SECTION C:
Fuel Guide ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 7
SECTION D:
Operation
Fueling ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 8
Inspection Before Operation ⋯⋯⋯⋯⋯⋯⋯⋯ 8
Operation ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 9
Adjusting Water Temperature ⋯⋯⋯⋯⋯⋯⋯ 9
Flow Rate and Water Temperature ⋯⋯⋯⋯ 10
Turning Unit Off ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 10
Preventing Freeze Up ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 10
Long Term Inactivity ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 11
SECTION E:
Routine Maintenance
Inspection and Maintenance ⋯⋯⋯⋯⋯⋯⋯ 12
Inspection and Maintenance Items ⋯⋯⋯⋯ 12
SECTION F:
Troubleshooting ⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯⋯ 13
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BE SURE TO FOLLOW THE FOLLOWING INSTRUCTIONS.
The instructions which are contained in this manual are classified into the following two types, which are
"WARNING" and "CAUTION". These instructions are intended to provide important information for safe
operation.
"WARNING" indicates the possibility of causing the user a fatal accident or serious injury if the water heater
is incorrectly operated.
"CAUTION" indicates the possibility of causing the user injuries or material damages if the water heater is
incorrectly operated.
WARNING
1. Never use any fuel other than ASTM D3699 1-K Kerosene, ASTM D396 Low Sulfur No. 1 Fuel Oil, or
ASTM D975 Ultra Low Sulfur Diesel (ULSD).
NEVER USE GASOLINE! Use of such fuels can result in an explosion and/or fire and cause injury.
2. Never store flammable liquids or materials such as gasoline near the unit.
3. This unit should be installed by a licensed, authorized person(s) due to the necessity of making electri-
cal, water and fuel connections.
4. RISK OF BACKFIRE AND INDOOR AIR POLLUTION. Before operation make sure the flue pipe is free of
snow, icing, leaves, bird's nest or strong drafts.
5. RISK OF INDOOR AIR POLLUTION AND FIRE. Be sure the exhaust pipe is properly installed and connect-
ed. Aluminum tape may be used for sealing exhaust pipe connections.
6. RISK OF INJURY FROM MOVING PARTS AND ELECTRICAL SHOCK. Disconnect power cord before ser-
vicing unit.
7. This water heater is designed to be used no more than 4,922 FY. (1,500 m) above sea level. Burner
adjustments are required when: (1) water heater is installed with flue pipe (#20476401) above 4,992 ft.
(1,500 m); (2) water heat is installed with chimney kit (#20476430) above 3,280 ft, (1,000 m). Failure to
make appropriate adjustments may cause combustion failure. Contact your local dealer.
The water heater may have a failure of combustion at a high altitude
CAUTION
1. HOTTER WATER INCREASES THE RISK OF SCALD INJURY. Water heaters are intended to produce hot
water. Water heated to a temperature which will satisfy clothes washing, dish washing, and other sani-
tizing needs can scald and permanently injure you upon contact. Before changing temperature setting
make sure nobody is using a shower. High temperature setting increases the risk of scald injury.
Temperature has been set at factory to about 130°F.
2. RISK OF SCALD INJURY. When using a shower, feel the temperature of the water with your hand before
getting under the water.
3.
RISK OF SCALD INJURY. Do not touch hot water flowing from the temperature and pressure relief valve.
4. RISK OF BURN INJURY. Do not touch the flue pipe top or exhaust pipe. The insulated material provided
should be installed around the exhaust pipe. Due to high surface temperature, keep children away from
the unit.
1
SECTION A:
SAFETY TIPS
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OTHER PRECAUTIONS
1. This unit is only for indoor use. Avoid its exposure to rain or moisture.
2. Do not use for drinking or cooking until the water supply has been approved by local authorities.
3. Hot water (or cold water) left in heat exchanger or piping must not used for cooking or drinking.
4. When using a large amount of hot water the temperature may change, even though the temperature
setting has not been changed. Special caution must be taken if two faucets are open at the same time.
5. If the unit appears to be operating abnormally or in an emergency, turn off the unit and call an autho-
rized service person.
6. Use the following water quality.
7. Avoid the use of hard water. In regions where hard water is the only source, take advantage of a water
softener.
8. Do not use a damaged unit. If repairs are needed, contact your dealer.
9. Keep the area around the unit, the fuel tank and the flue pipe clean and free of flammable materials.
10. If you plan to be away from your home for a long period of time, shut-off the fuel valve on the fuel tank.
Press "POWER SWITCH" to "OFF" position and disconnect the power supply cord.
11. If the unit is not used for a long period of time, the fuel tank may contain water cause by condensation.
Be sure to check all filters and strainers for this condition, clean or replace filter elements before using
the unit.
12. The use of the water heater with the temperature selector knob at "B", "HOT", or "COLD" may propagate
bacteria growth in the water. In order avoid this, turn the temperature selector knob to "VERY HOT" once
a week to heat the water heater and water to a high temperature for approximately one hour.
13. Before changing the temperature setting, make sure that the water heater is not being used by any of
your family at any place in the house. All family members should be aware of this "Caution."
14. Fusible Link Valve (#10005597)
¡It is most important that the valve, depending on its use, be fully opened or fully closed.
¡The top nut on the valve (below the turn handle) is sealed and should never be tightened or
removed.
¡When installing fuel lines to the valve, be sure to check for fuel leakage.
¡A LEAKING VALVE SHOULD ALWAYS BE REPLACED.
15. When No. 2 fuel oil is used in an area where the temperature becomes less than 25˚F (-4˚C), it is recom-
mended the use of an additive with the fuel to prevent congeling. Check with a fuel suppy company for
the propre additive and mix.
16. Always check if there are leaks from the flue pipe by corrosion once a month. If repairs are needed,
contact your dealer.
2
Description
Maximum Levels
pH
6.5 to 8.5
Chloride
50 mg/L
Hardness
150 mg/L
Residual Chlorine
2 mg/L
OM-148(OP/E) 09.2.25 9:13 AM ページ 2

SAFETY FEATURES
1. Ignition Safety Device (Flame Sensor)
The unit will automatically stop all operations if ignition fails or if the flame fails during combustion.
''WARNING'' lamp will light.
2. Over Heat Protector
In order to prevent burns, the over heat protector automatically stops all operations if the water in the
heat exchanger reaches abnormally high temperatures due to temperature controller malfunction. The
''WARNING'' lamp will light.
3. Power Failure Recovery System
If power fails during water heater operation the unit will turn off. When power resumes the unit will
automatically reignite.
4. Fully Vented System
Flue pipe system provides outside air for combustion and vents all combustion products to the out-
doors.
5. Fusible Link Valve
If a household fire should occur, causing the fuel line or water heater to become extremely hot, the
fusible link valve will stop the fuel supply to the burner. This will prevent the fuel supply from the exter-
nal tank from continuing to flow into the house.
6. Fuel Strainer
Special strainer catches any dirt or impurities present in the fuel before it is sent to the burner.
7. Heat Exchanger Bi-Metal Switch
If the heat exchanger temperature becomes abnormally hot because of a malfunctioning thermostat, the
burner is automatically extinguished and the ''WARNING'' lamp will light.
8. Temperature Fuse
When the air around the heat exchanger rises to an abnormal level, the temperature fuse will blow and
the unit will turn off. The "WARNING" lamp will light.
9. Air Pressure Switch
When the air flow volume reduces or the flue pipe is clogged, the burner is automatically extinguished
and the "WARNING" lamp will light up.
3
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SPECIFICATIONS
Model: OM-148 (Type D)
Type: Combustion Type Pressure Vapor
Flue Pipe Forced Flue
Heating Supply System Instantaneous
Source of Water Direct Connection to Main Supply
Ignition: High Voltage Discharge Spark
Fuel: ASTM D3699 1-K Kerosene,
ASTM D396 Low Sulfur No.1 Fuel Oil, or ASTM D975
Ultra Low Sulfur Diesel (ULSD)(1)
Efficiency: 88% (2)
Hot Water Input: 148‚000 BTU/h
(Input value of No.1 Fuel Oil)
Fuel Consumption: 1.05 gal/h
Capacity of Heat Exchanger: 5.10 gal
Fuel system: External tank (3)
Dimensions (W x H x D): 12-5/8'' x 27-3/4'' x 22-1/2''
Weight: 82 lbs. Empty
Vent Pipe Hole: 4-3/4 diameter
Maximum Length of Vent Pipe System: 10 ft., 3 bends or less
Electrical Rating: 120 Volts AC, 60 Hz
Ignition - 120W
Burning - 98W
Required Accessories: Fuel filter, Temp & pressure relief valve, Flue pipe
installation kit (Part #20476440) or Chimney installation
adapter kit (Part #20476430 or #20476415)
Safety Device: Over-heat protector, Ignition safety device,
Heat exchanger bi-metal switch,
Temperature fuse, Fusible link valve
Exhaust Air Temperature: less than 500°F
Nozzle: Quantity of Vapor 0.85 GPH
Spraying Angle 60°
Spray Pattern Delavan Type XA
Temperature Fuse: 282°F
Electric Current Fuse: 5 A
(1) You are recommended to use the low sulfur fuel.
(2) Heat and vaporized water are produced by the combustion process of this water heater. This rating
does not take into account heat loss due to condensation of water vapor.
(3) External tank to be purchased from local suppliers.
4
SECTION B:
SPECIFICATIONS
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DIMENSIONAL OUTLINE
5
Temperature and
Pressure Relief Valve
Installation Opening
(NPT 3/4) Female
Exhaust Outlet
ø2-3/4"(ø70mm)
Drain Outlet
(NPT 1/2) Male
Air Intake Inlet
ø2-3/4"(ø70mm)
Access Cover
Water Supply
Inlet
(NPT 3/4) Male
Hot water Supply
Outlet
(NPT 3/4) Male
Junction Box
Front Panel
5-1/8"
(130mm)
5-1/8"
(130mm)
3/16"
(5mm)
22-1/2"(570mm)
6/1/4"
(160mm)
8-1/2"
(215mm)
5-1/8"
(130mm)
5-1/8"
(130mm)
27-3/4"(705mm)
3/4"
(19mm)
23"(585mm)
12-5/8"(320mm)
OM-148(OP/E) 09.2.25 9:13 AM ページ 5

CONTROL PANEL
CONSTRUCTION
6
Temp Selector Knob Power Switch
Operation Lamp
Burner Lamp
Warning Lamp
CAUTION
HOTTER WATER INCREASES THE
RISK OF SCALD INJURY.
BEFORE CHANGING TEMPERATURE
SETTING SEE INSTRUCTION
MANUAL.
ON/OFF
POWER
THERMOSTAT
B
HOT
A
COLD
VERY HOT
130°F
WARNINGBURNEROPERATION
Main Circuit Board
Thermistor
Fuel Pump Ignition Transformer
Fusible Link Valve
Heat Exchanger
Air Pressure Switch
Inteke Air Duct
Blower Motor
Igniter
Burner
Heat Exchanger Bi-Metal Switch
Flame Sensor
Strainer
OM-148(OP/E) 09.2.25 9:13 AM ページ 6

The OM-148 is designed for use with ASTM D3699 1-K Kerosene, ASTM D396 Low Sulfur No.1 Fuel Oil, or
ASTM D975 Ultra Low Sulfur Diesel (ULSD) only. Use of low-quality oil will cause burner performance to
drop, leading to abnormal combustion and reduced the unit life.
Purchase only ASTM D3699 1-K Kerosene, ASTM D396 Low Sulfur No.1 Fuel Oi, or ASTM D975 Ultra Low
Sulfur Diesel (ULSD) in non-red cans reserved exclusively for fuel and marked accordingly with the word
"KEROSENE", "NO.1 FUEL Oil", or "ULTRA LOW SULFUR DIESEL".
To avoid accidented use of gasoline or other high volatile liquids, always store your fuel in a separate area.
What to Buy...
ALWAYS: Clean and high-quality ASTM D3699 1-K Kerosene, ASTM D396 Low Sulfur No.1 Fuel Oil, or
ASTM D975 Ultra Low Sulfur Diesel (ULSD).
You are recommended to use the low sulfur fuel.
ALWAYS: Fuel free of contaminants, water or cloudiness.
NEVER: Gasoline, alcohol, white gas, camp stove fuel or additives.
NEVER: Yellow or sour-smelling fuel.
How to Store It...
ALWAYS:
Store in a clean container, non-red in color, clearly marked
"KEROSENE", "NO.1 FUEL OIL", or "ULTRA LOW SULFUR DIESEL".
ALWAYS: Store away from direct sunlight, heat sources or extreme tem-
perature changes.
NEVER: In a glass container, or one that has been used for other fuels.
NEVER: For longer than six months.
NEVER: In the living space.
Why It is Important...
Good, clean oil is essential for safe and efficient water heater operation.
Poor quality or contaminated fuel can cause:
¡Excess tar deposits in the burner area and flue pipe
¡Incomplete combustion
¡Reduced unit life
Use of a highly volatile flammable fuel such as gasoline can produce uncon-
trollable flames, creating a severe fire hazard.
7
SECTION C:
FUEL GUIDE
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FUELING
WARNING: Use ASTM D3699 1-K Kerosene, ASTM D396 Low Sulfur No.1 Fuel Oil, or ASTM D975 Ultra Low
Sulfur Diesel (ULSD) only. Never use gasoline, thinner, benzene, light oil or waste oil, or any
other high volatile liquids.
CAUTION: Make sure that the fuel is clean and free from dirt and water. Water and dirt may cause com-
bustion failure and shorten the life of components such as the fuel pump.Be sure to refuel
before the tank runs out. Avoid having the fuel tank and fuel line run empty.
REMOVING AIR TRAP
When operating for the first time or when refueling an empty tank, air may be trapped in the fuel line, mak-
ing ignition difficult. In this situation, after removing the trapped air thoroughly from the fuel filter at the fuel
tank outlet, follow the procedures below:
1. Press "POWER SWITCH" to "OFF" position. Disconnect the power supply
cord.
2. Release the two (2) screws from the front panel and remove the front
panel.
3. To catch the fuel which will drain out, put a small container under the
strainer.
4. Loosen the screw on top of the strainer. Immediately wipe off any spilled
fuel.
5. Remove the trapped air thoroughly. Failure to remove all the air will cause improper ignition and may
extinguish the unit.
6. Tighten the screw after removing trapped air.
7. Reconnect the power supply cord. Press "POWER SWITCH" to "ON" position.
Note: In the event of an ignition failure, press "POWER SWITCH" to "OFF" position and after
10 seconds press "POWER SWITCH" to "ON" position once again.
INSPECTION BEFORE OPERATION
1. Before turning on the POWER SWITCH, make sure that the water supply inlet is open and that water runs
out properly by opening a hot water faucet. If not, check the drain valve to see if it has been left open.
2. Check for water leaks in the pipes.
3. Be sure there is a sufficient amount of fuel in the tank and that there are no leaks in the pipe line.
4. Be sure the power supply is properly connected and grounded to the unit.
5. Be sure the area around the water heater is clear of flammable materials such as gasoline, thinner or
flammable vapors.
6. Be sure the exhaust and flue pipes are securely connected and that there are no leaks.
7. Do not operate the unit without water in the heat exchanger. The heat exchanger may be damaged.
8
SECTION D:
OPERATION
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OPERATION
CAUTION: ¡Hotter water or high temperature setting increases the risk of scald injury.
¡Thermostat has been set at factory to about 130°F.
¡Risk of scald injury. When using a shower, feel the temperature of the water with your hand
before getting under the water.
¡When using a large amount of hot water the temperature may change, even though the tem-
perature setting has not been changed. Special caution must be taken if two faucets are open
at the same time.
1. Open the fuel tank valve.
2. Press "POWER SWITCH" to ''ON''. "OPERATION" lamp will come on. Automatic operation is based upon
the temperature of water inside the heat exchanger. ''BURNER'' lamp is lit when the burner is in its
operation mode.
NOTE: When operating for the first time or after running out of fuel, ignition may not occur because of
air in the fuel line. In that case, remove air as described in the previous section.
ADJUSTING WATER TEMPERATURE
CAUTION: ¡Hotter water or high temperature setting increases the risk of scald injury.
¡Thermostat has been set at factory to about 130°F.
¡Risk of scald injury. When using a shower, feel the temperature of the water with your hand
before getting under the water.
¡Risk of scald injury. Before changing the temperature setting, make sure that the water
heater is not being used by any of your family at any place in the house.
¡When using a large amount of hot water the temperature may change, even though the tem-
perature setting has not been changed. Special caution must be taken if two faucets are
open at the same time.
¡The use of the water heater with the temperature selector knob at "B", "HOT", or "COLD" may
propagate bacteria growth in the water. In order avoid this, turn the temperature selector
knob to "VERY HOT" once a week to heat the water heater and water at high temperature for
approximately one hour.
To increase the hot water temperature, turn the temperature selector knob clockwise. To decrease the hot
water temperature, turn the temperature selector knob counterclockwise.
9
Position of Temperature Selector Knob
VERY HOT
B
HOT
A
COLD
Hot Water Temperature
around 155°F
around 145°F
around 110°F
around 90°F
around 70°F
CAUTION
HOTTER WATER INCREASES THE
RISK OF SCALD INJURY.
BEFORE CHANGING TEMPERATURE
SETTING SEE INSTRUCTION
MANUAL.
ON/OFF
POWER
THERMOSTAT
B
HOT
A
COLD
VERY HOT
130°F
WARNINGBURNEROPERATION
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OPERATING AT HIGH TEMPERATURE
CAUTION: Risk of scald injury. Before changing temperature setting make sure that the water heater is not
being used by any of your family at any place in the house.
NOTE: ¡Seasonal change of water temperature from the main water source results in different hot
water temperature supplied. Use hot water supply faucet to control hot water temperature,
or readjust temperature setting.
¡The hot-cold mixing faucet is recommended to ensure safe and comfortable use of the water
heater. Choose a mixing faucet which can provide a comfortable water temperature with less
temperature fluctuation.
¡After installing the mixing faucet, set the temperature selector knob at the position of "VERY
HOT" and then gradually adjust the water temperature by adding cold water to your prefer-
able level. Sufficient care must be taken not to misoperate this adjustment, which may result
in scalding your hands.
FLOW RATE AND WATER TEMPERATURE
NOTE: Whenever high temperature water is required for continuous demand, lessen the flow rate.
Whenever low temperature water is required, the flow rate may be increased.
The flow rates are calculated under the conditions of standard installation and normal usage so
that they will vary according to installation, usage and temperature.
TURNING UNIT OFF
1. Press "POWER SWITCH" to ''OFF'' position. All lamps will go out.
2. Close the fuel tank valve.
PREVENTING FREEZE UP
In order to prevent any kind of damage or leaks caused by freezing, keep the pipes heated at all times, as
specified below.
CAUTION: In order to prevent the water heater from freezing or develop a leak, regardless of being used in
a cold region or in a warm or hot region, the water supply piping, hot water supply piping,
drain pipe, valves, expansion tank, and temperature & pressure relief valve are to be protected
with sufficient insulation materials (by wrapping with heat insulation or by equipping an freeze
prevention heater).
10
SUMMER
SPRING & FALL
WINTER
SEASON INCOMING
WATER TEMP
HOT WATER
TEMP FLOW RATE
80°F
60°F
40°F
120°F (40°F RISE)
120°F (60°F RISE)
120°F (80°F RISE)
6.1 GPM
4.0 GPM
3.0 GPM
CAUTION
HOTTER WATER INCREASES THE
RISK OF SCALD INJURY.
BEFORE CHANGING TEMPERATURE
SETTING SEE INSTRUCTION
MANUAL.
ON/OFF
POWER
THERMOSTAT
B
HOT
A
COLD
VERY HOT
130°F
WARNINGBURNEROPERATION
OM-148(OP/E) 09.2.25 9:13 AM ページ 10

LONG TERM INACTIVITY
When you do not plan to use the unit for an extended period, the following procedures are recommend-
ed.
1. Turn the unit off.
2. Disconnect the power supply cord.
3. Close the fuel tank valve securely.
4. After closing the main water supply valve, open up all the faucets.
5. Open the drain valve on the bottom of the unit.
6. Pull up the lever of the temperature and pressure relief valve.
NOTE: If the water heater is not used in the winter season or in a cold region where the water supply
is frozen, or if it is not used for a long period of time, the water heater should be drained and
related piping system shut off completely.
When re-supplying water in the water heater and system:
1. Close the air exit valve, if it is provided for the piping.
2. Close the drain valve.
3. Pull down the lever of the temperature and pressure relief valve.
4. Close all the hot and cold mixing faucets once.
5. Fully open the main water supply valve.
6. First slowly open the valve for the hot and cold mixing faucet which is located in the farthest posi-
tion and gradually increase the flow rate as water starts flowing continuously.
NOTE: Since the water heater and piping system still have much air left after they are drained, a flash
flow of water may be caused by such air pressure when re-supplying water through them. First
open the valve carefully and gradually increase its opening to "Full Open" when the water flow
becomes stable. When air bubbles disappear in the water, fully open the valve for hot and cold
mixing faucet.
7. Also flow water through other hot and cold mixing faucets by the procedure of item 6 above.
8. Fully open the feed fuel valve for the fuel tank.
9. Connect the power supply cord.
10. Press the the "POWER SWITCH" to "ON" position.
11. Next open the valve for hot and cold mixing faucet, so hot water will flow out.
Operation start of the water heater in a cold region:
Before starting the water heater, open a valve for a hot and cold mixing faucet to make sure that water flows
out. Neither water flow nor smooth water flow occurs when the water heater and piping system are frozen.
If this happens, wait until such frozen water is melted and re-start the operation of the water heater when
water flows properly.
11
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INSPECTION AND MAINTENANCE
WARNING: RISK OF INJURY FROM MOVING PARTS AND ELECTRICAL SHOCK. Disconnect the power sup
ply cord before inspecting and servicing unit.All repairs should be left to professionals. RISK OF
BACKFIRE AND INDOOR POLLUTION. Before operation make sure the flue pipe is free of snow,
icing, leaves, bird's nest or strong drafts.
CAUTION: RISK OF BURN INJURY. Do not touch the flue pipe top and the exhaust pipe.
Annual maintenance is recommended for most efficient operation.
When inspecting, ALWAYS do the following.
a. Press the Power Switch to OFF position.
b. Disconnect the power plug from the receptacle.
c. Close the fuel feed valve.
When inspecting, NEVER do the following.
a. Do not remove the thermistor.
b. Do not adjust the pressure of the fuel pump.
INSPECTION AND MAINTENANCE ITEMS
1. FLAMMABLE IN THE ENVIRONMENT (REGULARLY)
Remove all flammable material from the area.
2. FUEL LEAKS (REGULARLY)
Always check for oil leaks. If a leak is found, shut down the unit until the problem is corrected.
3. FUEL FEED LINE INSPECTION (REGULARLY)
Check for fuel leaks from the fuel feed line. Replace it if any cracks or leaks are found.
4. WATER LEAKS (REGULARLY)
Check the heat exchanger for water leaks. Always correct if found.
5. ODOR OR SOOT (REGULARLY)
If you notice soot at exhaust pipe fittings, exhaust gas may be leaking from the pipe joints. Consult your
dealer.
6. DUST (ONCE A MONTH)
Check for dust inside of the unit and the bottom (base).
7. WATER INSIDE THE FUEL TANK (ONCE A MONTH)
Remove any water or waste particles that accumulate inside the fuel tank.
8. FUEL STRAINER (Part# 20476487) / FUEL FILTER (Part# 17185384) (ONCE A MONTH)
Vibration, noise, ignition and combustion failure could be caused by water or waste particles in the fuel
strainer and the fuel filter. Clean the strainer and filter once a month.
9. FLUE PIPE (ONCE A MONTH)
A clogged flue pipe will cause improper combustion.
Inspection for any clogging or soot accumulation should
be done at least once every year. Make sure not to place
combustibles in the flue pipe area.
Make sure that exhaust gas is not leaking from the flue pipe.
Also check whether there are leaks from pipe joints.
12
SECTION E:
ROUTINE MAINTENANCE
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10. TEMPERATURE AND PRESSURE RELIEF VALVE (ONCE A MONTH)
The temperature and pressure relief valve may become immovable at times due to corrosion of
pipes or mineral deposits In the pipes. Pull up the lever of the temperature and pressure relief
valve every month and make sure the valve is movable.
11. PLUG AND RECEPTACLE (ONCE A MONTH)
Make sure the plug is free of dust. Be sure plug fits receptacle securely.
12. BURNER INSPECTION (ONCE SIX MONTH)
Check the burner and combustion area for soot. Clean if found.
13. GASKETS AND WASHERS (ONCE SIX MONTH)
Check for water leaks caused by improper sealing of the water pipe. If there are leaks, gaskets
or sealant must be replaced.
14. FLAME SENSOR (PHOTOELECTRIC CELL) (ONCE SIX MONTH)
a. Take out the ignition transformer by removing the two (2) bolts and
remove the four (4) screws from the blower bracket C-assembly.
b. Take out the flame sensor which is located to the right upper part of the
burner inside the cabinet.
c. If the beam receiving surface of the flame sensor becomes dirty or cont-
aminated, the unit will not operate properly. The beam receiving sur-
face should be wiped with a soft cloth every 6 months.
d. To install, make the protruding section at the side of the flame sensor
agree with the slot on the bracket and insert the flame sensor firmly up
to the bottom. (Use pliers with long tapered noses to nip and install the
flame sensor, which facilitates installation work.)
15. BLOWER MOTOR (ONCE SIX MONTH)
Make sure there is no dust on the blower motor fan.
16. HEAT EXCHANGER (ONCE A YEAR)
Open the drain valve at least once a year to drain the heat exchanger. Pull
up the lever of the temperature and pressure relief valve to allow air to
enter the heat exchanger.
WARNING: RISK OF INJURY FROM MOVING PARTS AND ELECTRIC SHOCK.
Disconnect the power supply cord before servicing unit. All repairs should be left to
professionals.
WARNING: Do not re-use the unit until the cause of the problems have been determined.
CAUTION: RISK OF BURN INJURY. Do not touch the unit and the heat exchanger while in hot.
If there Is any abnormality, determine for the causes from the list below and perform the specified measure.
Consult your dealer if problems cannot be corrected from this chart.
13
SECTION F:
TROUBLESHOOTING
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14
PROBLEM
POWER LAMP FAILS
TO TURN ON
ALARM LAMP
LIGHTS AFTER
TURNING ON.
BLOWER MOTOR
OPERATES BUT IGNI-
TION FAILS.
EXTINGUISHED
AFTER IGNITION
NOISE FROM FUEL
PUMP
NOISY COMBUS-
TION
HOT WATER TEMP
TOO LOW
SOOT ACCUMULA-
TION
WATER LEAKAGE
FUEL LEAKAGE
FROM FUEL PIPE
Disconnected power supply cord
Thermistor malfunction
Out of water in heat exchanger
Flame sensor malfunction
Light is received on the receiving
surface of photoelectric cell
Bi-metal switch activated
Abnormal location and adjust-
ment of electrode
Igniter malfunction.
Abnormal lowering of electrical
voltage
Out of fuel
Air pocket in fuel pipe.
Clogged fuel strainer
Circuit board malfunction
Temperature fuse activated.
Air pressure switch activated or
malfunction
Circuit board malfunction
Stained light-intercepting surface
of flame sensor
Flame sensor malfunction
Air pocket in fuel pipe
Air lock in fuel line
Clogged intake line and pump
Fuel flow too much
Fuel flow too little
Fuel nozzle malfunction
Improper installation of flue pipe
Thermistor malfunction
Hot water supply beyond capacity
Dusty blower motor fan
Improper installation of flue pipe
Fuel flow too much
Fuel nozzle malfunction
Water leakage from heat
exchanger (Heat exchanger
malfunction)
Gasket malfunction
Loose connection of fuel pipes
Connect power supply cord.
Consult your dealer.
Supply water.
Consult your dealer.
Consult your dealer.
Consult your dealer.
Consult your dealer.
Consult your dealer.
Contact electricians.
Check fuel gauge on fuel tank; refuel.
Remove air pocket.
Clean strainer.
Consult your dealer.
Consult your dealer.
Check air intake line.
Replace it.
Replace it.
Consult your dealer.
Replace it.
Remove air pocket completely.
Remove air.
Consult your dealer.
Consult your dealer.
Consult your dealer.
Replace it.
Re-install properly.
Consult your dealer.
Close hot water faucet partially.
Consult your dealer.
Re-install properly.
Consult your dealer.
Replace it.
Consult your dealer.
Replace it.
Consult your dealer.
CAUSE SOLUTION
OM-148(OP/E) 09.2.25 9:13 AM ページ 14

TOYOTOMI U.S.A., INC. ("TOYOTOMI") warrants each product and any parts thereof sold by it to be free from defects in
materials or workmanship under normal use and service for TWELVE (12) MONTHS* (see below for extended warranty) from
the date of delivery to the original purchaser at retail subject to the following terms and conditions:
WHAT IS COVERED: Product or any parts thereof that are defective in materials or workmanship.
WHO IS COVERED: The original purchaser at retail.
WHAT WE WILL DO: TOYOTOMI will either repair or replace, at its option, all defective parts free of charge that are covered by
this limited warranty through the nearest authorized dealer or distributor of TOYOTOMI.
WHAT YOU MUST DO FOR WARRANTY SERVICE: You must return the defective product or part to any authorized dealer or
distributor of TOYOTOMI with this LIMITED WARRANTY and a copy of the bill of sale or credit card charge receipt or other
document evidencing the date of the Product's delivery. If service is not available locally, please contact:
TOYOTOMI U.S.A., INC.
Customer Service Department
Brookfield, Connecticut
Tel: [phone]
*In addition to the warranty period stated above, an extended nine years (10 years from date of purchase) warranty is
offered on the water heaters for the following part:
Heat exchanger.
The heat exchanger is prorated at the following:
Years 2nd to the 5th covered at 100% of the part cost,
Years 6th to the 8th covered at 50% of the part cost,
Years 9th and 10th covered at 25% of the part cost.
NOTE: THE EXTENDED WARRANTY POLICY IS APPLICABLE ONLY FOR THE REPLACEMENT OF THE ORIGINAL FACTORY-
INSTALLED PART THAT HAS FAILED WITHIN THE TIME LIMITATIONS AS INDICATED. REPLACEMENT PARTS ARE
WARRANTED FOR THE REMAINDER OF THE ORIGINAL PART WARRANTY PERIOD. LABOR IS NOT COVERED ON THE
EXTENDED WARRANTY.
WHAT IS NOT COVERED:
1. This warranty does not apply to any defect due to the negligence of others; failure to install, operate or maintain unit in
accordance with instructions (Installation, Operating and Maintenance Instructions are furnished with each new unit);
unreasonable use; accidents; freezing , alteration, use of unauthorized or non-standardized Toyotomi parts and
accessories; electrical malfunction, i.e., as resulting from power surges, short circuit, etc.; use of any power source, water
or fuel other than that specified in owners manuals; or repair by anyone other than a service facility specified by Toyotomi.
2. This warranty only extends through the first installation of the unit and terminates if the unit is moved or reinstalled at a new
location.
3. Normal wear of parts, including nozzles, electrodes, filters, etc.
4. Any product that has been damaged as a result of natural disasters, including, but not limited to, lightning, fire, earthquake,
hurricanes, tornadoes or floods.
5. Any product that has been damaged as a result of operation with insufficient water or water which causes deposits or
corrosion.
6. Installations of equipment for other purposes than residential applications.
7. This warranty does not cover shipping costs.
THE FOREGOING EXPRESSES ALL OF TOYOTOMI'S OBLIGATIONS AND LIABILITIES WITH RESPECT TO THE QUALITY OF
PRODUCT FURNISHED BY IT. ALL OTHER WARRANTIES, EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. TOYOTOMI SHALL NOT BE LIABLE
FOR THE LOSS OF USE OF THE PRODUCT, INCONVENIENCE, LOSS OR ANY OTHER DAMAGES, DIRECT OR
CONSEQUENTIAL, ARISING OUT OF THE USE OF, OR INABILITY TO USE, THE PRODUCT OR DAMAGES RESULTING FROM
OR ATTRIBUTABLE TO DEFECTS IN THE PRODUCT.
No one other than TOYOTOMI has authority to extend or modify the terms of this Limited Warranty in any manner whatsoever.
Some states do not allow the exclusion or limitation of incidental or consequential damages or limitations on how long an
implied warranty lasts, so these limitations or exclusions may not apply. This Limited Warranty gives you specific legal rights
and you may also have other rights, which vary from state to state.
LIMITED 10 YEAR WARRANTY
Rev. 3/09 Printed in Japan
4731003051
TOYOTOMI U.S.A., INC.
604 Federal Road, Brookfield, CT 06804
www.toyotomiusa.com
This manual supersedes earlier editions. PART No.20476696
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