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Excel Pro Natural Gas 6.6 GPM Tankless Gas Water Heater *Whole House and Hydronic Applications * Includes Free Flue Kit



This compact , yet  powerful unit - with gas inputs up to 136,000 BTU per hour - can meet all the hot-water needs of a small to medium American home or apartment.  

Comes with a Free Flue Kit consisting of an elbow and 2' straight piece.

Can be Exhausted Vertically (Rooftops) or Sideways (Wall Exhaust)

Designed to virtually do anything a 40-gallon tank-type water heater can do and much more

The Wall mounted   Excel Pro is design to work with hydronic baseboard or radiant floor heating applications, as well as provide domestic hot water to plumbing fixtures and appliances. 

 Modulated tankless water heaters change their heat output in response to the flow rate of water running through the unit.  


Only 4 left


     Brand New, Factory Sealed

    Excel Pro ** Natural Gas **

    Free Shipping 

    6.6 gpm

     Whole House 

    Free Flue Kit

    Stainless Steel CAT III Flue 3.5" Diameter Included (20") + Elbow - See Pictures

    It can vent vertically (roof) or horizonally (wall)

    This compact , yet  powerful unit - with gas inputs up to 136,000 BTU per hour - can meet all the hot-water needs of a small to medium American home or apartment.  

    Designed to virtually do anything a 40-gallon tank-type water heater can do and much more

    The Wall mounted   Excel Pro is design to work with hydronic baseboard or radiant floor heating applications, as well as provide domestic hot water to plumbing fixtures and appliances. 


    Comes with a Free Flue Kit consisting of an elbow and 2' straight piece.


    Can be Exhausted Vertically (Rooftops) or Sideways (Wall Exhaust)


    LCD Display Control: Just set the desired water temperature 

    The Excel Pro has an energy factor of 0.84-0.85.   

     Excel Pro: Modulating Technology 

    Tankless water heaters can be further divided into two categories according to their heating capability: "full on/full off" versus "modulating". 

    Full on/full off units do not have a variable power output level; the unit is either fully on or completely off. This can cause an annoying and possibly hazardous variation of hot water temperature, as the flow of water through the heater varies. 

    Modulated tankless water heaters change their heat output in response to the flow rate of water running through the unit.  

    The Excel Pro comes with a display panel where you can set the output temperature and regardless of water flow the unit modulates the fire power. 

     Pure Copper Heat Exchanger *


     * see detail at the end of listing on pure copper heat exchanger used by top of the line tankless  gas  water heater manufacturers like  Rinnai, Takagi,  Rheem and  Noritz

     Features & Benefits

              • Super compact 14.5" x 23" x 5.5" size
      •             84%+ thermal efficiency
      •            136,000 BTU maximum input
      •             6.6 gallons/ minute capacity at 35F degree rise
      •             Minimum activation flow rate of 0.5 gpm
      •             Electronic ignition
        • Vents vertically or horizontally with 2'  
            •       stainless steel flue included
      •            Can be used in recirculation and space heating             applications
    • Excel  Service Promise

      Excel  strives to provide  customers with excellent customer service and strongly believes that customer feedback is integral to achieving excellence. 

      Excel agents receive extensive product training to aid inquiries in minimal wait times.  

      Excel strives to promptly return your inquiry within 24 business hours.

      Customer Service Operating Hours

      Monday - Saturday, 8am - 5pm EST 

    • Specs

    ·       Max Input (BTU) - 136,000

    ·       Min Input (BTU) - 20,000

    ·       Capacity at 35 (°F) Rise (gpm) - 6.6

    ·       Capacity at 45(°F) Rise (gpm) - 4.4

    ·       Min Flow Rate - 0.5 gpm

    ·       Temp Range (°F) - 100 to 160

    ·       Temp Stability (°F) - +/- 2 °

    ·       Default Temp (°F) - 120

    ·       Energy Factor - 84%+

    ·       Thermal Efficiency - 83%+

    ·       Installation Options - Indoor

    ·       Dimensions (w x h x d) - 14.5" x 23" x 5.5"

    ·       Weight (lbs.) - 36

    ·       Inlet Connection - 1/2" NPT

    ·       Outlet Connection - 1/2" NPT

    ·       Gas Connection -  1/2"NPT or ¾" BSP 

    ·       Max Water Pressure - 150 psi

    ·       Min Water Pressure - 10 psi

    ·       Venting Options - Stainless Steel CAT III Flue Included (20") + Elbow - See Pictures

    ·       Vent Maximun Run - 35 feet





    Excel Pro water heaters are warranted by the manufacturer (EXCEL) through Excel  America.  ExcelAmerica will furnish a replacement heat exchanger and will furnish a replacement of any other part which fails in normal use and service within the applicable periods specified below, in accordance with the terms of this warranty. The Excel Water Heating replacement will be warranted for the unexpired portion of the original warranty. This warranty will be valid only for water heaters in possession of the original purchaser as recorded on the invoice.

    The Heat Exchanger
    If the heat exchanger fails within fifteen (15) years after the original installation and operation, Excel Water Heating at its choice, will furnish a replacement heat exchanger or replace the whole unit for a Pretested refurbushed unit  
    (shipping excluded) .     

    However, if the water heater is installed in other than a single family dwelling, or is used as a circulating heater in any application, this heat exchanger warranty is limited to two (2) years from date of original installation and operation. 
    Heat Exchanger breakage due to freeze cracking  is excluded.

    All Other Parts
    If any other part fails within three (3) years after original installation and operation, Excel Water Heating will furnish a replacement part free of charge (shipping excluded).

    Shipping Costs
    Shipping Costs for warranty returns and replacement parts or replacement units will be paid by Customer

    This warranty does not cover any labor costs associated with service, removal or re-installation of part(s). All such costs must be borne by the Purchaser.
    The customer can ship  the unit back to our Service Center at  his cost and we will quote repair labor costs.

    This warranty will not apply:
    1. to defects or malfunctions resulting from failure to properly install, operate or maintain the unit in accordance with the printed instructions provided;
    2. to damage or abuse, accident, neglect or freezing and other acts of nature;
    3. to damage resulting from operation with either the thermocouple or overheat sensor removed;
    4. to failure of the heat exchanger resulting from the operation of the water heater in a corrosive atmosphere or at water temperatures exceeding the maximum rating, or if the water heater is not supplied with potable water.
    5. to defects or damage cause by any attachment or modification, including any energy-saving device.
    6. Freeze Crack .

    Note: The water heater must be free of damaging scale deposits and not subject to gas pressures greater than those shown on the rating plate, which must not be altered, defaced or removed.

    Please be advised that our product warranty is void with respect to stolen goods. Further, we reserve the right to require a legitimate sales receipt showing that the product was purchased from one of our customers in order to provide warranty coverage.
    How to make a claim 
    For warranty parts replacement, please contact ExcelAmerica at Techsupport at excelamerica dot com.
     If your installer or service person is unable to provide warranty service, please contact us at:   888-254-4818  Monday - Saturday, 8am - 5pm EST 

    Details such as proof of purchase, date and location of install, serial number and other related installation details will be required to process any warranty claim. The alleged defective component(s) or part(s) must be returned in accordance with Excel’s procedure then in force for handling goods returned for the purpose of inspection to determine cause of failure.  Excel  reserves the right to deny any warranty claim based on the inspection of the returned component(s) or part(s). 

    No one is authorized to make any other warranties on behalf of Excel Water Heating. It is expressly understood that the replacement warranty of Excel Water Heating shall be in lieu of any and all other warranties, express or implied, including warranties of merchantability or fitness for a particular use or purpose, and further that Excel Water Heating shall not be liable for any loss or damage directly or indirectly arising from the use of the hot water heater, or for any consequential damages arising from such use (including damages from water leakage). Excel Water Heating's sole liability with respect to any defect shall be for the replacement of defective part(s). Some states do not allow such limitations and exclusions, so the above may not apply to you. This warranty gives specific legal rights. You may also have other rights which vary from state to state.



    Q.   What is a tankless water heater?

    A.   Most people in North America currently use a storage tank water heater to provide hot water in their homes. A storage tank water heater wastes energy by  keeping water hot 24 hours a day, even while you’re at work or sleeping. 

    A tankless water heater, on the other hand, does not store hot water. It heats the water instantly as you use it.


    Q.   How can a tankless water heater heat water instantly?

    A.   When you open a faucet, the flow of the water triggers the heater to turn on. Whether you use gas or electricity, the powerful gas burners   will turn on, rapidly heating the water as it passes through the unit. The water is heated instantly, and the time it takes to obtain hot water is directly related to the distance the hot water has to travel from the water heater to where hot water is being used. The burners or elements then shut down when you shut off the hot water. The energy that is consumed is only for the hot water that is being used.


    Q.   What are the advantages of using a tankless water heater?

    A.   Because a tankless water heater turns on when you open a hot water faucet and turns off when you close the faucet, the energy that is consumed is only for the hot water that is being used. Since there is no storage of water, and thus no constant heating and re-heating of stored water, you’re not wasting energy heating water when you don’t need it, such as when you’re sleeping or not at home. This energy savings translates to dollar savings for you and reduced impact on our environment. Furthermore, since a tankless water heater heats the water as you use it, you can have an endless supply of hot water, provided you size the unit appropriately 


    Q.   How much money can I save?

    A.   Depending on which model of tankless water heater you purchase, and what size storage tank you have now, and if it runs on gas or electricity, you could save anywhere from 5% to 69% off your hot water heating bill. How? Most homes use hot water for a cumulative total of about one hour per day, yet they typically keep 40 or 50 gallons (oftentimes more) of water hot 24 hours a day. Having a system that eliminates the storage and heats water only as you use it can dramatically reduce your energy consumption.


    Q.   Can it really provide an endless supply of hot water?

    A.   Yes. Because storage tank water heaters store a finite amount of water, when that amount is used up your shower goes cold and you have to wait for the heater to heat the water back up (this is known as recovery time). Because a tankless water heater heats the water as it passes through the heater, you can never run out, provided flow limitations are not exceeded  


    Q.   Are there other benefits of a tankless water heater?

    A.   There are many advantages of having a tankless water heater in your home. Besides the money savings, endless hot water and smaller impact on the environment, a tankless water heater:

    • Is very small and can hang on the wall, thereby saving you valuable floor space.
    • Is designed with replaceable parts and is built with such materials as copper, stainless steel, and aluminum so as to last a lifetime. Energy savings is only one segment of savings—with proper care this could be the only water heater one needs in a lifetime.
    • Is almost entirely recyclable, so if you ever decide to replace it, it doesn’t have to go to the landfill.
    • Will not develop a corrosive leak like a storage tank water heater, saving you from expensive water damage in your home. 
      Note: A tankless water heater can leak if it is exposed to freezing temperatures or has a manufacturing defect.
    • Maintains its efficiency throughout the lifetime of the unit. Storage tank water heaters decrease in efficiency over time due to mineral build-up inside the tank. This is due to the fact that storage tank water heaters store hot water, giving those minerals a chance to settle out and bake from the heat onto the walls of the tank, and onto the heating element in electric models, thereby reducing heat transfer.

    Q.   Will I still get the hot shower I’m used to now?

    A.   Yes, provided you buy the right tankless heater for you  . Tankless water heaters are able to function at a variety of temperatures that you can choose, and can produce hot water at the same flow rate as your standard single-headed shower provides now.


    Q.   Will one tankless water heater service my entire house?

    A.   Yes. You must choose the proper model to suit your home’s hot water needs, which is based upon the maximum flow of hot water you need at any one time  . We sell tankless water heaters that are capable of handling one shower at a time and others that can sustain a maximum of three showers operating at the same time.


    Q.   What if I have very hard water?

    A.   Since tankless water heaters do not store hot water, minerals have less of an opportunity to settle out of the water column and build up inside the heat exchanger. Additionally, the flow of hot water through the coiled heat exchanger flushes the product each time hot water is used. The use of a water softener is fine with a tankless water heater, and is recommended if you commonly experience hard water problems in your home.


    Q.   What limitations do tankless water heaters have?

    A.   Because this type of water heater heats the water as you use it, the volume of hot water that it can deliver is directly correlated to the amount of its energy input. The bigger the burners or heating elements in the unit, the higher the volume of hot water that it can deliver. Today tankless water heaters come in various sizes to suit most homes’ needs. Even if you need to be operating multiple showers at once, tankless water heaters can keep up  


    Q.   How do I properly size a tankless water heater for my home?

    A.   You need to choose the model that can deliver the volume of hot water to meet your needs. The best method for sizing this type of water heater is to know how many showers each model can run simultaneously. We have models that can run either one or two showers at a time. And remember, a tankless water heater can deliver endless hot water, shower after shower. 


    Q.   Can I fill a hot tub with a tankless water heater?

    A.   Yes. Because tankless water heaters provide an endless supply of hot water, you can fill a tub of any size. It is only a question of time, meaning that our larger units can fill a tub faster than our smaller units. Keep in mind that some tubs draw water at high flow rates, so it may be necessary to limit the flow so that the tankless water heater can adequately heat the water that is being called for.


    Q.   Is this a new technology?

    A.   No. Europe, Asia and South America, where energy costs are more expensive than here in North America, have been using tankless water heaters for 75 years. ExcelAmerica  has been selling and supporting tankless water heaters in the United States since 2002. However,   Americans are now more energy conscious and are aware of the carbon footprint of their appliances and are   just now learning of this technology and its benefits 




    Heat exchangers are devices that transfer heat in order to achieve desired heating or cooling.

     An important design aspect of heat exchanger technology is the selection of Pure Copper (Oxygen Free)  to conduct and transfer heat fast and efficiently.

    Pure Oxygen Free Copper has many desirable properties for thermally efficient and durable heat exchangers. First and foremost, copper is an excellent conductor of heat. This means that copper's high thermal conductivity allows heat to pass through it quickly. Other desirable properties of copper in heat exchangers include its corrosion resistance, biofouling resistance, maximum allowable stress and internal pressure, creep rupture strength, fatigue strength, hardness, thermal expansion, specific heat, antimicrobial properties, tensile strength, yield strength, high melting point, alloyability, ease of fabrication, and ease of joining. 

    The combination of these properties enable copper to be specified for heat exchangers in industrial facilities, HVAC systems, vehicular coolers and radiators, and as heat sinks to cool computers, disk drives, televisions, computer monitors, and other electronic equipment.[6] Copper is also incorporated into the bottoms of high-quality cookware because the metal conducts heat quickly and distributes it evenly.


    Non-copper based heat exchangers or Regular Copper with tin bath cheaper versions are also available in the market , they are less efficient and have a short life.

    Pure copper heat exchanger are customarily used only by top of the line tankless gas  water heater manufacturers like  Rinnai, Takagi, Rheem , Noritz and this new line of Excel Water Heaters