Mr Heater MH9BX Manual
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WARNINGS
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CARBON MONOXIDE HAZARD
This appliance can produce carbon monoxide which has no odor.
Using it in an enclosed space can kill you.
Never use this appliance in an enclosed space such as a camper, tent, car or home
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FOR YOUR SAFETY
If you smell gas:
- Do not attempt to light appliance.
- Extinguish any open flames.
- Disconnect from fuel supply
FOR YOUR SAFETY
Do not store or use gasoline or other flammable vapors and liquids in the vicinity of this or any other appliance
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Early signs of carbon monoxide poisoning resemble the flu, with headache, dizziness and/ or nausea. If you have these signs, heater may not be working properly. Get fresh air at once! Have heater serviced.
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Every time hose or tank is connected to unit, connection must be checked for leaks in one or more ways: Apply soapy water to connection, look for bubbles, listen for hiss of escaping gas, feel for extreme cold, smell for rotten egg odor. Do not use if leaking!
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Fuels used in liquefied propane gas appliances, and the products of combustion of such fuel, can expose you to chemicals including benzene, which is known to the state of California to cause cancer and cause birth defects or other reproductive harm, for more information go to www.P65Warnings.ca.gov
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This product can expose you to chemicals including lead and lead compounds, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information visit www.P65Warnings.ca.gov
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Any changes to this heater or its controls can be dangerous.
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FIRE OR EXPLOSION HAZARD
If you smell gas:
- Do not attempt to light appliance and make sure appliance is in the "OFF" position.
- Extinguish any nearby flames.
- Shut off the cylinder fuel supply valve, if so equipped.
- Disconnect the disposable fuel cylinder, if so equipped.
- Leave the area immediately.
- Allow gas to dissipate 5 minutes.
- If gas smell has dissipated from the area, the appliance, and fuel supply. follow gas connection procedures. If you smell gas again, follow steps 1-6 and have appliance serviced.
Failure to follow these instructions could result in fire or explosion, which could cause property damage, personal injury, or death.
SPECIFICATIONS
Model No. | MH9BX |
Gas Type | Propane (LP) |
Input (Btu/Hr) | 4,000/9,000 |
Minimum Ambient Temperature | -18˚C/ 0˚F |
Clearance To Combustibles |
Top | 30" |
Front | 24" |
Sides | 6" |
Rear | 0" |
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Improper installation, adjustment, alteration, service or maintenance can cause injury or property damage. Refer to this manual. For assistance or additional information, consult a qualified installer, service agency or gas supplier.
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- When operating the heater at altitudes over 7,000 FT above sea level the heater may shut off. (Please read the GENERAL INFORMATION)
- Some carpets or linoleum surfaces may discolor if heater is placed directly on these floor coverings.
ODOR FADE WARNING
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ASPHYXIATION HAZARD
- Do not use in unventilated areas.
- The flow of combustion and ventilation air must not be obstructed.
- Proper ventilation air must be provided to support the combustion air requirements of the heater being used.
- Refer to the specification section of the heater's manual, heater dataplate, or contact the factory to determine combustion air ventilation requirements of the heater.
- Lack of proper ventilation air will lead to improper combustion.
- Improper combustion can lead to carbon monoxide poisoning leading to serious injury or death. Symptoms of carbon monoxide poisoning can include headaches, dizziness and difficulty in breathing.
GENERAL SAFETY INSTRUCTIONS
THIS IS A HEATING APPLIANCE. DO NOT OPERATE THIS APPLIANCE WITHOUT THE FRONT GRILL INSTALLED. DO NOT ATTEMPT TO WARM OR COOK FOOD ON THIS HEATER.
- Do not use non-approved attachments on this heater.
- Due to high temperatures, the appliance should be located out of traffic and away from combustible materials.
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Children and adults should be alerted to the hazard of high surface temperatures and should stay away to avoid burns or clothing ignition. - Young children should be carefully supervised when they are near the appliance.
- Do not place clothing or other flammable material on or near the appliance.
- Do not operate heater in any moving vehicle.
- This heater is for outdoor use only.
- GAS PRESSURE AT HEATER IS REGULATED AND FIXED AT 1 1" W.C. WHEN USING A REMOTE HOSE CONNECTION DO NOT REGULATE OR REDUCE PROPANE TANK SUPPLY PRESSURE TO HEATER!
- REGULATOR IN HEATER MUST ALWAYS BE IN PLACE DURING OPERATION.
- Any safety screen or guard removed for servicing the appliance must be replaced prior to operating the heater.
- The appliance should be inspected before each use. Frequent cleaning may be required. The control compartments, burner and circulating air passageways of the appliance must be kept clean, see MAINTENANCE.
- DO NOT use this heater if any part has been under water. Immediately call a qualified service technician to inspect the heater and to replace any part of the control system and any gas control, which has been under water.
- When used without adequate combustion and ventilation air, this heater may give off excessive CARBON MONOXIDE, an odorless, poisonous gas.
- Some people - pregnant women, persons with heart or lung disease, anemia, those under the influence of alcohol, those at high altitudes - are more affected by carbon monoxide than others.
- When heater is placed on the ground, make sure the ground is level and keep any objects at least 24 inches from the front of the heater. THIS HEATER IS EQUIPPED WITH A TIP OVER SWITCH THAT WILL SHUT THE HEATER OFF IF THE HEATER TIPS OVER HOWEVER, DO NOT LEAVE HEATER UNATTENDED OR WHERE CHILDREN MAY CAUSE THE HEATER TO TIP OVER. NEVER OPERATE THE HEATER WHILE SLEEPING!
- Heater must not be exposed to flammable vapors or liquids during lighting or operation.
FUEL GAS ODOR
Propane (LP) gas and natural gas have man-made odorants added specifically for detection of fuel gas leaks.
If a gas leak occurs you should be able to smell the fuel gas. Since propane (LP) gas is heavier than air you should smell for the gas odor low to the floor. ANY GAS ODOR IS YOUR SIGNAL TO GO INTO IMMEDIATE ACTION!
- Do not take any action that could ignite the fuel gas. Do not operate any electrical switches. Do not pull any power supply or extension cords. Do not light matches or any other source of flame. Do not use your telephone.
- Get everyone out of the building and away from the area immediately.
- Close all propane (LP) gas tank or cylinder fuel supply valves, or the main fuel supply valve located at the meter if you use natural gas.
- Propane (LP) gas is heavier than air and may settle in low areas. When you have reason to suspect a propane (LP) gas leak, keep out of all low areas.
- Use your neighbor's phone and call your fuel gas supplier and your fire department. Do not re-enter the building or area.
- Stay out of the building and away from the area until declared safe by the firefighters and your fuel gas supplier.
- FINALLY, let the fuel gas service person and the firefighters check for escaped gas. Have them air out the building and area before you return. Properly trained service people must repair any leaks, check for further leakages, and then relight the appliance for you.
ODOR FADING - NO ODOR DETECTED
- Some people cannot smell well. Some people cannot smell the odor of the man-made chemical added to propane (LP) gas. You must determine if you can smell the odorant in these fuel gases.
- Learn to recognize the odor of propane (LP) gas. Local propane (LP) gas dealers will be more than happy to give you a scratch and sniff pamphlet. Use it to become familiar with the fuel gas odor.
- Smoking can decrease your ability to smell. Being around an odor for a period of time can affect your sensitivity to that particular odor. Odors present in animal confinement buildings can mask fuel gas odor.
- The odorant in propane (LP) gas is colorless and the intensity of its odor can fade under some circumstances.
- If there is an underground leak, the movement of gas through the soil can filter the odorant.
- Propane (LP) gas odor may differ in intensity at different levels. Since propane (LP) gas is heavier than air, there may be more odor at lower levels.
- Always be sensitive to the slightest gas odor. If you continue to detect any gas odor, no matter how small, treat it as a serious leak. Immediately go into action as discussed previously.
CRITICAL POINTS TO REMEMBER
- Propane (LP) gas has a distinctive odor. Learn to recognize these odors. (Reference Fuel Gas Odor and Odor Fading sections above.
- Even If you are not property trained in the service and repair of the heater, ALWAYS be consciously aware of the odors of propane (LP) gas.
- If you have not been properly trained in repair and service of propane (LP) gas then do not attempt to light heater, perform service or repairs, or make any adjustments to the heater on the propane (LP) gas fuel system.
- A periodic sniff test around the heater or at the heater's joints; i.e. hose, connections, etc., is a good safety practice under any conditions. If you smell even a small amount of gas, CONTACT YOUR FUEL GAS SUPPLIER IMMEDIATELY. DO NOT WAIT!
- When the heater is cold or at room temperature, it will take a few minutes for the burner tile to turn bright orange. This is normal and the heater is working properly. If burner tile is visibly flaming, turn heater off and call a qualified service technician.
Note: The heater is to be used outdoors, but may experience nuisance shutoffs due to certain wind conditions. - When the unit is lit, there should be about a quarter inch (1/4") border around the tile that will not turn bright orange. This is normal.
- When operating the heater for the first time, the top area of the reflector may discolor. This is also normal and is no reason for concern.
- The protective grill on the front of this heater is coated with a special high temperature resistant paint. When the heater is used for the first time, the grill may give off noticeable smoke or fumes. This is normal and will not occur during subsequent uses. The fumes are not harmful.
- Heater is designed to operate at altitudes up to 7,000 feet. When operating the heater at altitudes over 7,000 FT. above sea level, the unit may not burn as bright as in lower altitudes. This is normal. At higher altitudes, the heater may shut-off. If this happens, provide fresh air, wait 5 minutes and re-light. If the heater continues to shut off, there may not be enough oxygen available to feed proper combustion.
- Operating time will be approximately 3 to 6 hours on a one 1lb cyclinder and 48 to 1 10 hours on a 20 lb cylinder (based on "HI" and "LO" settings). Due to the properties of LP gas, runtimes can be significantly reduced when operating continuously at temperatures below 20ºF.
- This heater is equipped with a tip-over safety switch. Nuisance shut-downs may be experienced if the unit is bumped or moved. if this occurs simply relight the heater.
- Do not leave this appliance unattended while it is in operation. Keep children and pets away from the appliance at all times.
- LP -gas cylinders must be constructed and marked in accordance with the specifications for "Cylinders, Spheres and Tubes for Transporation of Dangerous Goods, CAN/CSA B339".
- Use only VAPOR WITHDRAWAL propane supply. If there is any question about vapor withdrawal, ask your propane dealer.
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Always inspect propane cylinder and heater propane connections for damage, dirt, and debris before attaching propane cylinder. Do not use if head of cylinder is damaged, punctured or deteriorated.
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Do not operate heater unless control knob is locked in a position marked "hi", "lo" or "pilot". Never set control knob between locked positions. Poor combustion and higher levels of carbon monoxide may result.
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Do not try to adjust heating levels by using the propane tank shut off valve.
OPERATION
LIGHTING/OPERATING INSTRUCTIONS FOR USE WITH DISPOSABLE 1 LB PROPANE CYLINDERS
ALWAYS ATTACH OR DETACH CYLINDER OUTDOORS AWAY FROM FLAMES, OTHER IGNITION SOURCES, AND ONLY WHEN HEATER IS COOL TO TOUCH. NEVER SMOKE WHEN ATTACHING OR REMOVING PROPANE CYLINDER OR MAKING REMOTE CONNECTIONS!
- Use only 16.4 oz. (1 lb.) disposable cylinders that mate with No. 600 valve connection.
- Heater and attached cylinder must be in an upright position during operation.
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The heater must not be exposed to flammable vapors or liquids during lighting.
- Make sure four-position Control Knob is in "OFF" position. See Figure 1.
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- Swivel regulator outward for easy tank installation. Screw 1 lb. disposable LP-gas supply cylinder clockwise (from bottom) into portable heater until hand-tight. See Figure 2. Do not use thread sealant on this connection.
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- Check cylinder connection for leaks with soapy water at the threaded connection under the domed plastic cover where the cylinder screws into the regulator. SEE WARNING! ON DOMED PLASTIC COVER.
- Turn Control Knob counterclockwise to "PILOT" position and depress to light. See Figure 3.
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- After pilot lights, hold down for 30 -60 seconds and then release knob. Knob should return to fully extended position. See Figure 4.
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- To operate heater slightly depress knob and gently turn to lock in the "HI" position to light burner tile. Leave on "HI" position until burner tile turns bright orange.
- After burner tile has turned bright orange, adjust heat output by turning Control Knob to desired position ("LO" or "HI" setting).
Shutdown Instructions
- To shut off heater, slightly push down and turn Control Knob clockwise to "OFF" position.
- Do not operate, store or remove cylinder near flammable items or ignition sources.
LP-GAS CYLINDERS MUST BE DISCONNECTED FROM HEATER WHEN NOT IN USE!
LIGHTING/OPERATING INSTRUCTIONS FOR USE WITH HOSE CONNECTED TO A REMOTE CYLINDER WITH MAXIMUM SIZE 20 LBS
- This Heater may be used with a remote refillable propane cylinder ONLY when the cylinder is located outdoors and the Heater is used with Mr. Heater Hose No. F273701, F273702 or F272702 and fuel filter F273699. Fuel filter must be replaced annually. (NOTE: Do not operate without the fuel filter as fuel contamination may damage the heater.) Or use F273704 Buddy series hose. Fuel filter not required.
- Inspect the hose before each use of the heater. If there is excessive abrasion or wear, or the hose is cut, replace prior to using the heater with one of the Mr. Heater Hose No's. shown above.
- The propane cylinder must include a listed overfilling protection device as well as a collar to protect the cylinder valve.
- Heater must be in an upright position during operation.
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The heater must not be exposed to flammable vapors or liquids during lighting.
- Make sure four-position Control Knob is in "OFF" position. See Figure 1.
- Swivel regulator outward for easy hose installation. Screw hose connector into regulator on heater and screw connector on other end of hose into LP-gas supply cylinder valve. Tighten all hose connections. DO NOT use thread sealant on any of these connections.
- Mr. Heater strongly recommends using disposable fuel filter F273699 to trap any oil substances when connected to a remote cylinder that can make heater inoperable.
- Open valve at LP-gas supply cylinder.
- Check all hose connections for leaks with soapy water at the threaded connection under the domed plastic cover where the hose connector screws into the regulator and at LP-gas supply cylinder. SEE WARNING! ON DOMED PLASTIC COVER.
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After turning heater off, wire guard will remain hot. Allow to thoroughly cool before storing.
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NEVER bring a refillable propane cylinder indoors. A fire or explosion can occur causing property damage, serious injury or death!
- Turn Control Knob counterclockwise to "PILOT" position and depress to light. See Figure 3. This may take longer to purge air from the supply hose depending on the length of the hose being used.
- If pilot does not light, hold down for approximately 30 seconds; release and depress again. Repeat until pilot lights.
- After pilot lights, hold down for 30 -60 seconds and then release knob. Knob should return to fully extended position. See Figure 4. The pilot should remain lit.
- To operate heater slightly depress knob and gently turn to lock in the "HI" position to light burner tile. Leave on "HI" position until burner tile turns bright orange.
- After burner tile has turned bright orange, adjust heat output by turning Control Knob to desired position ("LO" or "HI" setting).
Shutdown Instructions
- To shut off heater, shut off propane at supply tank, allow heater to use-up propane in supply line until heater shuts off, then slightly push down and turn Control Knob clockwise to "OFF" position.
- When not in use, the gas must be turned off at the LP-gas supply cylinder. As stated before allow heater to use up propane in supply line until heater shuts off. When the LP-gas supply cylinder is not disconnected from the heater, the heater and the cylinder must be stored outdoors, in a well ventilated space, out of reach of children, and must not be stored in a building, garage or any other enclosed area.
- Indoor storage of the heater is permissible only if the cylinder is disconnected and removed from the heater. Cylinders must be stored outdoors out of the reach of children and must not be stored in a building, garage or any other enclosed area.
MAINTENANCE
- Always keep the heater area clear and free from combustible materials, gasoline and other flammable vapors and liquids.
- Keep the vent areas (slots in the bottom and top of the heater) clear at all times.
- Visually inspect the pilot flame and burner periodically during use. The pilot flame should be blue in color (not yellow) and will extend to the thermocouple. The flame will surround the thermocouple just below the tip. See Figure 5.
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- A slight yellow flame may occur where the pilot flame and main burner flame meet. The burner should be bright orange (with a slight blue color around the border, a red-orange haze that is visible on the ceramic tile is acceptable) and without a noticeable flame.
- A blue flame that rolls out at the top of the ceramic tile indicates an accumulation of dust, lint or spider webs inside the housing assembly and main burner assembly. If the pilot is yellow or the burner has a noticeable flame, cleaning may be required.
It is necessary to periodically check the burner orifice and burner venturi to make sure that they are clear of things such as insect nests and spider webs that may accumulate over time. A clogged tube can lead to a fire. - Use the following procedure to inspect the casing assembly and main burner assembly.
Cleaning Instructions (Refer to Exploded Parts):
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Allow heater to thoroughly cool before performing any maintenance.
- Remove disposable 1 lb. cylinder from heater or turn OFF gas supply at remote cylinder valve, and disconnect hose from heater.
- Remove (4) four screws that secure the rear cover (ref. # 7) to the Heater.
- Pivot cover outward from bottom. Release from 2 top clips. Set aside.
- Remove (4) four burner retaining screws and fuel line from burner assembly. Remove burner assembly (ref. # 16) from back of housing.
- Inspect interior of housing for accumulation of dust, lint or spider webs. If necessary, clean interior housing with a vacuum cleaner or apply air pressure. Do not damage any components within the housing assembly when you are cleaning.
- Inspect and clean main burner orifice (threaded into orifice holder). Orifice holder (ref.# 19) is attached to the burner assembly venturi with (2) two screws.
- Inspect and clean pilot (mounted to bracket) by using a vacuum or apply air pressure through the holes in the pilot indicated by the arrows in Figure 5.
- Apply air pressure (max. 30 psi.) into ceramic tile of burner assembly and the venturi tube to remove dust, lint or spider webs.
- Reassemble main burner orifice holder onto the burner assembly.
- Reinstall burner assembly into the heater housing.
- Reinstall fuel line and check for leaks.
- Install heater back cover.
- The exterior of the heater can be cleaned with a damp cloth. Avoid the direct use of any aerosol or spray-on cleaners. Do not use abrasive materials or cleaners on the decals or control knob.
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Never use needles, wires or similar cylindrical objects to clean the pilot to avoid damaging the calibrated ruby that controls the gas flow through the pilot orifice.
OFFSEASON
- If the heater is to left "OFF" for a considerable period of time, the propane (LP) gas supply to the heater should be turned off as close to the gas source as possible. In the case of portable use, the gas should be turned off at the propane (LP) gas supply cylinder.
- If the heater is put into storage, make sure to disconnect the propane (LP) gas cylinder.
TROUBLESHOOTING
SYMPTOM |
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Spark electrode does not produce spark |
CAUSE | REMEDY |
- Spark electrode broken.
| - Replace ODS (Oxygen Depletion Sensor).
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- Igniter wire may not be attached to spark electrode.
| - Attach igniter wire.
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- Igniter wire damaged.
| - Replace igniter wire.
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- Piezo igniter is defective.
| - Replace gas valve assembly.
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SYMPTOM |
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Spark electrode produces spark but pilot does not light |
CAUSE | REMEDY |
- No gas to heater.
| - Install disposable cylinder or connect hose and filter where required and turn on valve at remote cylinder.
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- "PILOT" position not properly aligned.
| - Turn gas control knob to "PILOT" position and depress.
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- Pilot is blocked with foreign debris.
| - Clean pilot. See MAINTENANCE section.
|
SYMPTOM |
- Pilot flame does not stay lit when knob is released.
|
CAUSE | REMEDY |
- Improper pilot lighting.
| - Make sure that the control knob is completely depressed in the "PILOT" position and held long enough to purge air from lines.
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- Pilot flame not surrounding thermocouple.
| - Clean pilot, see MAINTENANCE.
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- Pilot Assembly is defective.
| - Replace Pilot Assembly.
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- Tip switch wires are disconnected.
| - Connect tip switch wires.
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SYMPTOM |
-
Main burner does not ignite |
CAUSE | REMEDY |
- Main burner orifice is blocked.
| - Clean burner - see Maintenance.
|
SYMPTOM |
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The unit keeps shutting OFF during normal operation |
CAUSE | REMEDY |
- Pilot is blocked.
| - Clean pilot. See MAINTENANCE section.
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- Inadequate fresh air opening.
| - Provide minimum fresh air opening of 9 square inches (example 3" x 3" opening).
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- Tip over switch activated from bumping heater.
| - Re-light.
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- Regulator defective.
| - Replace regulator.
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- Internal contamination.
| - Replace control valve and regulator.
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- For additional assistance or information, please call Technical services.
PURCHASING: Accessories may be purchased at any Mr. Heater local dealer or direct from the factory
FOR INFORMATION REGARDING SERVICE
Please call Toll-Free 800-251-0001
Or visit www.mrheater.com
Our office hours are 8:00 AM – 5:00 PM, EST, Monday through Friday.
Please include the model number, date of purchase, and description of problem in all communication.
PRODUCT REGISTRATION: Thank you for your purchase.
Please log in to http://www.egiregistration.com to register your product
MR. HEATER, INC., 4560 W. 160TH ST., CLEVELAND, OHIO 44135 • 800-251-0001
www.mrheater.com;
800-251-0001
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