Takagi MOBIUS Owner's manual

MOBIUS Water HeaterTakagi Industrial Co. USA, Inc.
Installation and Operation Instruction
MODEL T - M1
MOBIUS Water Heater
Gas Fired, Instantaneous, Tankless
Water Heater
Store these instructions near to the water heater for reference purposes.
TAKAGI INDUSTRIAL CO. USA Inc.
6 Goddard, Irvine, CA 92618
Tel. (949) 453 - 8388, FAX. [phone]
E-Mail: [email protected]
http://www.takagi-usa.com
FEATURES
θENDLESS HOT WATER SUPPLY
θON-DEMAND HEATING
θPILOT-LESS SYSTEM
θCOMPACT, SPACE SAVING
θCOMPUTERIZED CONTROLS
θCOMPUTERIZED SAFETY DEVICES
θMULTI-UNIT INSTALLATION READY

FOR YOUR SAFETY - READ BEFORE OPERATING
FOR YOUR SAFETY - This product must be installed and serviced by a professional
Plumbing or Gas licensed service-trained technician. Installation and/or operation could
create carbon monoxide gas and other dangerous gases, which can cause serious injury
or death. Improper installation and/or operation will void the warranty.
WARNING: If the information in this manual 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 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.
•A trained technician, qualified installer, or service agency, must perform installation
and service.
WARNING: To install this unit correctly, you must follow the procedures in this manual.
If you do not do this, the warranty offered by Takagi Industrial Co. USA, Inc. will be
voided.
Do not make any changes to the water heater, or to its gas controls, gas orifices,
wiring or draft. Any modifications may void the warranty. If the unit must be modified
because of special conditions, talk with a factory representative before beginning any
changes.

CONTENTS
Introduction …………. 4
For Your Safety …………. 4
Operation …………. 6
•General …………. 6
•Temperature …………. 7
•Freeze Prevent Device …………. 7
•Winterizing …………. 7
Installation …………. 8
•General Instruction …………. 8
•Outdoor Installation …………. 9
•Indoor Installation …………. 11
•Combustible Air Supply…………..11
•Venting Instructions …………..12
•Vent Connections …………..12
•Vent Termination …………..13
•Gas Supply and pipe …………. 14
•Water Connections …………. 15
•T & P Relief Valve …………. 16
•Electrical Connection …………. 17
•Wiring …………. 18
•
Starting The System …………. 19
Operating Instructions …………..19
Maintenance and Service …………. 24
Cleaning the Heat Exchanger ……… 25
Trouble Shooting …………. 25
Trouble Shooting Flow Chart……….. 26
Part Diagram …………. 30
Part List …………. 34
MOBIUS Water Heater Application….36
Temperature Chart …………. 38
SPECIFICATIONS
Natural Gas Input Min. 25,000 Btu
Max. 235,000 Btu
LPG Input Min. 25,000 Btu
Max. 225,000 Btu
Gas Connection ¾” NPT
Water Connection ¾” NPT
Water Pressure Min. 15 psi
Max. 150 psi
Natural Gas Pressure Inlet Min. 5” WC
Max. 10.5” WC
LP Gas Pressure Inlet Min. 11” WC
Max. 14” WC
Manifold Pressure Natural 2.2” WC
Propane 2.7” WC
Weight 70 lbs.
Dimensions 24”x18”x 9”
Ignition Electronic Ignition
Electrical Supply AC 120 V
***
•Inlet gas pressure must be within above value.
•High altitude, before install in areas over 4,500 feet above sea level. Contact the
manufacturer for a high altitude.
•Check the rating plate to insure this product matches your specifications.
•Takagi - USA is constantly improving our products, therefore specifications are subject to
change without prior notice.

INTRODUCTION
This manual provides information necessary for the installation, operation, and maintenance
of the MOBIUS Model T-M1 water heater.
The model designation is listed on the rating plate, which is attached to the front of the water
heater. Please read all application and installation procedures completely before doing the
installation. If you have any problems or questions regarding this equipment, consult the
Takagi Industrial Co. USA, Inc. or local factory representative. Experience has shown that
most operating problems are caused by improper installation.
FOR YOUR SAFETY
PLEASE READ THIS MANUAL CAREFULLY AND FOLLOW IT FOR YOUR SAFETY.
1. Follow all local codes, or in the absence of local codes, follow the most recent edition of
the National Fuel Gas Code, ANSI Z223.1/NFPA 54.
2. Properly ground the unit in accordance with all local codes or in the absence of local
codes, with the National Electrical Codes, ANSI/NFPA 70.
3. Carefully plan where to install the MOBIUS Water Heater. Ensure that the heater will have
enough combustible air, proper ventilation, and will be located where water leakage will
not cause damage. If there is a possibility of water damage install a suitable drain pan
under the unit, but make sure that it does not restrict combustible airflow.
4. Check the rating plate for the correct gas type, gas pressure, water pressure, and
electrical rating. If this unit does not match your requirements, do not install.
RATINGPLATE

5. If any problem should occur, turn off all hot water taps and turn off the gas. Call a trained
technician, the Gas Company, or the manufacturer.
6. WARNING: Do not disconnect the electrical supply if the ambient temperatures will be
near freezing. The Freeze Prevention Device will only work if the unit has proper electrical
power. The Freeze Prevention Device is rated for temperatures down to 5ºF (-15ºC) in a
wind free environment. Wind chill factor can cause the MOBIUS Water Heater to freeze
and be damaged at temperatures above 5ºF (-15ºC). Refer to the section on Winterizing
and the Freeze Prevention Device for more information. Weather related damage to the
heat exchanger will not be covered under the warranty.
7. WARNING: Before bathing or showering always check the water temperature. Do not
leave children or the infirm without supervision in a shower or bath. The water
temperature is factory set at 140ºF (60ºC) to maximize the amount of hot water available
without an optional temperature remote controller. Water temperatures over 125ºF can
cause severe burns instantly, or death from scalds.
8. WARNING: Do not use this appliance if any part has been underwater. Immediately call a
certified and trained technician to inspect and service the unit if necessary.
9. WARNING: Do not store or use gasoline or other flammable vapors and liquids in the
vicinity of this or any other appliance.
10.WARNING: Do not reverse the water and gas connections, this will damage your heater
and can cause severe injury or death from scalds. Follow the diagram below when
installing the MOBIUS water heater.
Pressure relief Valve HOT COLD GAS

OPERATION
GENERAL
The MOBIUS Water Heater is an instantaneous, tankless water heater designed to supply an
entire household or commercial hot water utilizing total efficiency. The principle behind the
MOBIUS Water Heater is simple. Once a hot water tap is opened, water flows through the
MOBIUS Water heater. The water flow sensor automatically commands the computer to
electronically ignite the burners and the computer monitors the water temperature, water flow
rate, and gas flow the insure you get the right amount of hot water with right temperature.
While gas is being burned, the “fire on” lamp will be lit. Computer will modulate gas supply to
gas valve and modulate water flow for steady out put hot water temperature.
0.75 gallons per minute is required to turn the burners on, but after the burners are ignited,
the flow rate can drop to 0.6 gallons per minute to maintain and keep the water heater on. As
long as water, gas and electricity are supplied, there will be an endless flow of hot water. The
water heater will turn on when a tap is opened, and it will turn off when the tap is closed.

Temperature
The water temperature has been set on the computer by the factory to be Maximum 140º F
(60º C). In order to achieve lower water temperatures, cold water needs to be mixed in with
the hot, or an optional part No. TM-RE10 can be installed allowing manual adjustment of the
output temperature for lower or higher.
WARNING: Temperatures above 125º F (52º C) can cause severe burns or death from
scalding. Children, disabled and the elderly are at high risk of being injured. Feel the water
temperature before bathing or showering. Do not leave children, disabled, and the elderly
without supervision.
MOBIUS water heater will produce a flow rate of hot water that is depend on the inlet water
temperature and the setting on the TM-RE10. Refer to the flow vs. temperature chart for the
output capabilities end of this installation manual.
Freeze Prevention Devices
This unit comes equipped with heaters that discourage the unit from freezing, but for this
freeze prevention system to operate there has to be electrical power to the unit.
The freeze prevention devices will not work if the electrical power source is
disconnected. The unit has been rated for temperatures down to 5º F (-15º C) in a wind free
environment. A wind chill factor will cause the unit to freeze at temperatures above 5º F (-15º
C). Do not install the water heater in an area with extremely cold weather. This will void your
warranty and Takagi - USA will not be responsible for any damage that occurs.
CAUTION: The pipe heaters are located on the MOBIUS Water Heater only. Any hot or
cold water pipes located outside of the unit will not be protected. Properly protect and
insulate these pipes from freezing.
Winterizing
If the heater will not be used for a long period of time or if the temperatures will drop below 5º
F (-15º C) with the wind chill factor, turn off the heater and drain the unit of water. This will
keep it from freezing and being damaged. Follow these instructions carefully:
1. Turn off the power supply to the MOBIUS Water Heater.
2. Close the manual gas control valve located outside your heater.
3. Close the manual water shut off valve located on the water supply line.
4. Open all hot water taps in the house. (Bathroom, kitchen, laundry room, etc.). When the
water flow has ceased, close all hot water taps.
5. Have a bucket or pan available to catch the water as it drains from the T-M1 drain plugs.
Remove the drain plugs to drain all the water out of the unit.
6. Let sit for 5 minutes.
7. Securely screw the drain plugs back into place.
To restart heater, follow these steps:
1. Make sure all hot water taps are closed and the drain plugs are securely attached.
2. Purge the water line of debris.
3. Turn on the manual water control valve located on the water supply line.
4. Open all the hot water taps to verify water flows to the taps. Then close hot water taps.

5. Turn on the manual gas control valve located on the gas supply line.
6. Turn on the power supply to the MOBIUS Water Heater.
DRAIN DRAIN AND FILTER
INSTALLATION
General
All gas water heaters require careful and correct installation to insure safe and efficient
operation. This manual must be followed exactly.
1. Read the For Your Safety section in the beginning of this manual.
2. The regulator is preset at the factory. It is computer controlled and should not need
adjustment.
3. Maintain proper space for servicing. Install the unit so that it can be connected or removed
easily.
4. The electrical connection requires a means for switching off the power supply.
5. Avoid installing the unit in an area with high levels of dust, sand or debris. These particles
may clog the air vent or impair the function of the fan, leading to improper combustion.
Regular maintenance is needed in these environments.
6. Do not install the unit where the exhaust vent is pointing into any opening in a building or
where the noise may disturb neighbors.
Accessories
Check that all parts listed below were included with the unit.
Installation Manual, Warranty Card and Optional Part Information
This section is for the installer. The installer is responsible for the correct installation of
the MOBIUS Water Heater.
For Your Safety: Only a certified and trained service technician or qualified plumber may
service or install your product.

OUTDOOR INSTALLATION
Follow all local codes. In the absence of local codes, follow the National Fuel Gas Code
ANSI Z221.23.
Install the water heater in an open, uncovered area, and maintain the following minimum
clearances. The MOBIUS water heater must be installed hanging from a wall.
Piping side (Bottom) 12”
Front (Maintenance space) Open
Back of heater 1”
Top of heater 36”
Do not install this water heater under an overhang without a 3 feet clearance between the
MOBIUS water heater and eaves or any obstacles. The area under an overhang must be
open to three sides. In case install two or more unit manifold, side clearance will be 0.5”.
WARNING: Do not have the flue terminal pointing toward any opening into a building. Do not
locate your heater in a pit or location where gas and water can accumulate.

WARNING: Do not install the heater where water, debris, or flammable vapors may get into
the flue terminal. This may cause damage to the heater and manufacture warranty will void.
WARNING: In the USA, do not install the water heater vent terminator within 4 feet of any air
intake opening into a building. In Canada do not install the water heater vent terminator within
10 feet any air intake opening into a building.
WARNING: Improper installation can cause nausea or asphyxiation from carbon monoxide
and flue gases which could result in severe injury or death. Improper installation will void
product warranty.
For high altitude installation above 4,500 feet, contact the manufacturer on how to handle this
situation.
WARNING: Use proper vent terminator to top of the water heater, when it install in outside or
Part No. TM-TV02 kit for outside installation as vent cap.

INDOOR INSTALLATION
FOR INDOOR INSTALLATION: ∗CUT PRESSURE SWITCH JUMP WIRE THEN INSTALL
4” VENT PIPE DIRECTLY ON FLUE OUTLET. ∗: PLEASE! Look inside unit.
Combustion Air Supply
The water heater should be located in an area where enough air is available for proper
combustion and ventilation of the surrounding area. Follow the latest edition of ANSI
Standard Z223.1 and any your local codes that are applicable.
In general these requirements specify that if the unit is installed in a confined space, there
must be permanent air supply openings.
Minimum recommended Air supply to water heater
Water heater size Outside air area Inside air area
Max. 235.000 BTU 59 Sq. IN 235 Sq. IN
Air Supply from Outside Building: When combustion air is supplied directly through an
outside wall, such as intake louvers openings into the dwelling. Each opening should give a
minimum free area of one square inch per 4000 BTUH of the total input ratings of all
appliances in the enclosed area.
Air Supply from Inside Building: When combustion air is supplied from inside the building,
Each opening should give a minimum free area of one square inch per 1000 BTUH of the
total input ratings of all appliances in the enclosed area. These openings should never be
less than 100 Sq. IN.
235 Sq. In.

Exhaust Fans and Ventilation: The MOBIUS water heater is equipped with a combustible
air detector to measure whether there is enough air for proper combustion. If there is not, the
water heater will not work until air is provided properly.
Any equipment, which uses air from an enclosed space, can deplete the air from that area.
This can result in exhaust flowing from the flue to the enclosed space, which could result in
the accumulation of dangerous exhaust fumes in the space where the water heater is
installed. Additional air must be supplied to compensate for any exhaust effect.
If a blower of fan is used to supply air to the water heater room, the installer should make
sure it does not create drafts, which could cause unwanted shutdowns. If a blower is
necessary to provide adequate combustion air to the water heater, a switch or equivalent
device must be wired into the water heater control circuit to prevent the water heater from
firing unless the blower is operating.
Venting Instructions
GENERAL
This water heater must be vented in accordance with "Venting of Equipment" section of the
latest edition of the National Fuel Gas Code, ANSI Z223.1 and all applicable local building
codes.
WARNING: Improper venting of this appliance can result in excessive levels of Carbon
Monoxide, which can result in severe personal injury or death.
Here are some general rules for venting system for MOBIUS water heater.
1. Place the water heater as close as possible to the vent.
2. The vent collar on the water heater must be fastened directly to an unobstructed vent
pipe.
3. Do not weld the vent pipe to the water heater collar. The weight of the stack must not
rest on the water heater. The flue must be easily removable for normal service and
inspection of the unit.
4. The water heater must not be common vented with a fireplace, wood stove or other
equipment.
5. Avoid terminating the water heater vent near any air-conditioning or air-supply fans.
These fans can pick up the exhaust flue products from the water heater and return
them to the building. This can create a health hazard.
6. Avoid using an oversized vent pipe or using extremely long runs of the pipe. This may
cause excessive cooling and condensation of flue gases.
A) Vent Connections
The MOBIUS water heater should be vented as Category I with Single-wall metal pipe. The
vent system must be gas tight. All seams and joint must be sealed with silicone sealant or
adhesive tape having a minimum temperature rating of 400º F. For best results, a horizontal
vent system should be as short and straight as possible with Category III stainless pipe.
When installing the vent system, all applicable national and local codes must be followed. If
thimbles, fire stops or other protective devices are going to be installed which will penetrate

any combustible or noncombustible construction, be sure to follow all applicable national and
local codes.
Fan assisted appliances: Follow the requirement as indicated in the latest edition of ANSI
Z233.1/NFPA 54.
The entire vent system must not exceed the size specified in table.
Venting
Diameter Max. No. of Elbow Max. Vertical or Horizontal run in Length
4” 3 Ea. 35 ft
For each elbow added, deduct 5 ft. from max. Vent length.
When the horizontal vent run exceeds 5 ft the following criteria must be observed;
•Support the vent run at 3 ft intervals with overhead hanger.
•Pitch up the vent run toward the vent terminal at a rate of 1/ 4” per foot.
Indoor Installation Clearances
Bottom (Plumbing side) Min. 12”
Front (Maintenance space) Suggested 24”
Min. 4”
Back of heater 1”
Sides Min. 2”
Top of heater Min. 12"
When MOBIUS installs with manifold system, side clearance will be 0.5”.
B) Vent Termination
A sidewall vent terminal must be used when the water heater is vented through a wall. The
manufacture recommends Takagi Parts No. TK-TV01 as a vent terminator. The vent terminal
provides a means of installing vent pipe penetrating through a wall. Locate this in
accordance with ANSI Z223.1/NFPA 54.
Install the vent terminal in a location that will not be blocked by snow or water flooded area.
Most areas have codes requiring the terminal to be 12 inches above the grade, but the
installer may determine it should be higher depending on local conditions and applicable city
codes.

GAS SUPPLY AND PIPING SIZING
This unit needs a manual gas control valve (system shutoff valve) that must be placed on the
unit before it is connected to the gas supply line.
Check the gas inlet pressure and that the type of gas matches the rating plate located on
your water heater. Insufficient gas pressure will cause your MOBIUS Water Heater to be
inefficient and not work properly. Size the gas supply piping correctly following
ANSI233.1/NFPA 54, or by local code.
The minimum and maximum inlet gas pressures are listed below:
Natural Gas Min. 5” WC
Max. 10.5” WC
Propane Gas Min. 11” WC
Max. 14” WC
12"
12"
4"
12"
12"
2" 2"

In order to get a correct reading of the inlet supply pressure, the water heater and all other
gas appliances sharing the gas supply line must be firing at maximum capacity when the
pressure is measured. Maximum gas pressures must not exceed this value. If the gas
pressure is insufficient, this may be the result of an undersized gas supply pipe. The
MOBIUS water heater will not perform to its maximum capabilities without enough gas supply.
After connecting the unit, check for gas leaks by applying soapy water to all gas fittings and
connections. Soap bubbles are a sign of gas leaks.
This appliance and its individual shut-off valve must be isolated from the gas supply piping
system by unplugging the unit and turning off the main gas valve during any pressure testing
of the gas supply piping system at test pressures equal to or less than ½ Psi. The appliance
and its gas connections must be leak tested before placing the unit in operation.
Always use approved connectors to connect the unit to the gas line. Always purge the gas
line of any debris before connection to the heater.
WARNING: Conversion of this unit from natural gas to propane or propane to natural gas
cannot be done in the field. Contact your local retailer or distributor to get the correct unit for
your gas type.
Recommend Gas pipe size for MOBIUS Water Heater
Distance from Gas Meter Pipe Size (inches)
0' - 20' 3/4"
20' - 80' 1"
80' - 300 1-1/4"
NOTE: These Tables are for Natural Gas (0.60 Specific Gravity) and base on Pressure Drop
of 0.5 Inch water columns. This tables are Gas pipe will supply gas straight to water heater
without any tab.
Water Connections
An approved manual water control valve must be placed on the cold water supply line. All
soldering materials and piping materials must be useable with potable water.
If the water heater is installed in a closed water system, means shall be provided to control
thermal expansion. Contact the water supplier or local plumbing inspector on how to control
this situation. After installing the water heater, purge the water line to remove all debris and
air from it. It may damage the heater if installer does not do this act.
There is a wire mesh filter on the coldwater inlet which discourages debris from entering the
heater. This will need to be cleaned periodically to ensure that the T-M1 has a long life cycle.

T&P Valve HOT COLD GAS
WARNING: Do not reverse the hot outlet and cold supply line connections to the MOBIUS
Water Heater. This will result in dangerous operation and void the warranty. Make sure the
hot and cold lines are connected properly. Refer to the FOR YOUR SAFETY section at the
front of this manual.
PRESSURE RELIEF VALVE
This unit does not come with an approved temperature and pressure relief valve, however an
approved temperature and pressure relief valve must be installed on the hot water outlet. A
“Tee” fitting should be used to attach the temperature and pressure relief valve.
The pressure relief valve must meet not exceed the following:
Pressure Relief 150 psi
The discharge capacity must be at least 235,000 Btu/hr. The discharge piping for the
temperature and pressure relief valve must be directed so that if it becomes necessary, no
one will be hurt and nothing will be damaged by the escaping water. Attach the run-off tube to
the temperature and pressure relief valve, and run the end of the tube to within 6" of the floor.
Do not install any reducing couplings, valves, or any other type of restriction in this line. This
run-off tube must be installed to allow free and complete drainage of both the valve and the
run-off tube.
If the temperature and pressure relief valve on the appliance discharges periodically, this may
be due either to thermal expansion in a closed water supply system, or a defective
temperature and pressure relief valve. If the T&P valve is the problem, replace it with a new
one. If not, contact the water supplier or a local plumbing inspector for how to correct this
situation.
The temperature and pressure relief valve must be manually operated once a year to check
for correct operation.
Should overheating occur, or should the gas supply fail to shut off, turn off the manual gas
control valve to the appliance.

Pressure relief Valve
CAUTION: The pipe heaters are located on the MOBIUS Water Heater only. Any hot or
cold water pipes located outside of the unit will not be protected. Properly protect and
insulate these pipes from freezing.
Electrical Connections
WARNING: The heater must be electrically grounded. Follow the requirements of the local
authority having jurisdiction. In the absence of such requirements, follow the latest edition of
the National Electrical Code ANSI/NFPA 70.
Do not rely on the gas or water piping to ground the metal parts of the water heater, because
plastic pipe or dielectric unions may isolate the water heater electrically. Service and
maintenance personnel who work on or around the water heater may be standing on wet
floors, and could be electrocuted by an un-grounded water heater.
CAUTION: Label all wires prior to disconnection when servicing controls. Wiring error can
cause improper and dangerous operation. Verify proper operation after servicing.
The MOBIUS water heater requires an electrical power supply of 120 VAC, 60 Hz, and it
must be properly grounded to function.
•A means for switching off the 120 VAC power supply must be provided.
•Wire the heater exactly as shown in the wiring diagram.
•A green screw is provided in the junction box for the grounding connection.
Refer to the wiring diagram. There is a copy of the wiring diagram located on the inside
panel of the appliance.

Wiring Diagram
Also wiring diagram is located on the inside panel of the appliance.
Electrical Rating: 120 VAC, 60 Hz, 0.8 A.
Note: If any of the original wiring supplied with this appliance must be replaced, it must be replaced with
appliance wiring material (180c) or its equivalent. Wires are available through the manufacturer.

STARTING THE SYSTEM
For your safety, read before operating.
a) This water heater 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, make sure that a gas leak is not evident by smelling the area around the
T-M1. Be sure to smell next to the floor because some gas is heavier than air and will
settle on the floor.
c) Use only a hand to turn the gas valve knob. Never use tools. If the knob will not turn by
hand, do not try to repair it, call qualified service technician. Force or attempted repair
may result in a fire or explosion due to the gas leakage.
d) Do not use this water heater if any part has been under water. Immediately call a qualified
service technician to inspect the water heater and to replace any parts that have been
under water.
WHAT TO DO IF YOU SMELL GAS
•Do not try to start the water heater.
•Do not touch any electrical switches, and do not use any phone in your building.
•Immediately call the gas supplier from somewhere else. Follow the gas supplier’s
instructions.
•If you cannot reach the gas supplier, call the fire department.
Operating Instructions
The MOBIUS Water Heater is an instantaneous, tankless water heater designed to supply
your entire household and commercial hot water needs utilizing total efficiency. The principle
behind the MOBIUS Water Heater is simple. Once you open a hot water tap, water flows
through the MOBIUS Water heater. The water flow sensor automatically commands the
computer to electronically ignite the burners and the computer monitors the water
temperature, water flow rate, and gas flow the insure you get the right amount of hot water
with right temperature hot water. After the burners are ignited the “fire on” lamp is lit.
Computer will modulate gas supply to valve and water flow. 0.75 gallons per minute is
required to turn the burners on, after the burners are ignited, the flow rate can be lowered to
0.6 gallons per minute to maintain and still keep the heater on.
Now as long as you have water, gas and electricity, you will get an endless hot water. Open a
hot water tap to turn on your water heater. Close the hot water tap to turn off your water
heater.

Normal Operation
To Turn on Your MOBIUS water heater
1. Open a hot water tap.
2. Burners will ignite. “Fire On” lamp will be lit.
3. Mix with cold water to get the correct temperature.
To Turn off your Flash water heater
1. Close the hot water tap
2. “Fire On” lamp extinguished.