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Flex King HD - Heavy Duty Flexible Chimney Liner for Tough Jobs and Wood Burning Systems

HD stands for Heavy Duty

Flex King HD  is the ultimate lining system for tough jobs and wood burning systems. Perfect for all wood burning appliances, especially those with tight chimney clearances and less than perfect flue conditions.

Why it's the best?

  • Superior Durability
  • Easy to Clean
  • Minimal Creosote Build-Up
  • Excellent Draft
  • Takes Abuse Like No Other Liner

Select your kit type:

Flex King Heavy Duty the most durable, best valued flexible chimney liner

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    *Note: If you have a terra cotta clay chimney
    flue lining, be sure to measure the true length and width of the
    inside of your chimney flue space.

    *If there is a terra cotta clay flue liner, does it protrude out of
    the top of the chimney at least 2 inches? If there are at least 2
    inches and the terra cotta clay is in good condition, you will use
    our stainless steel, terra cotta top plate that has a 1 1⁄2inch edge
    that goes all the way around (like a shoebox lid).

    *If your terra cotta clay flue is in bad shape at the top, you may
    need to just take a hammer and tap all around that terra cotta,
    taking it away to make the surface flat at the top of your chimney.
    In that case, you will simply use the flat top plate that comes with
    our liner kit.



    *Note: If you have a terra cotta clay chimney
    flue lining, be sure to measure the true length and width of the
    inside of your chimney flue space.

    *If it is on the back of the stove, is it parallel with the back of the stove or is it at an angle, like 45 degrees?

    *If it is at an angle you will use an insert stove adaptor (an insert liner kit) rather than a two-part tee with cleanout cap.


    Usually pellet stoves have an exhaust hole id of 3 inches. However, if you are going up more than 15 feet to the top of your chimney you need to use a pipe and/or flex liner that is 4 inches diameter.





    If you are only venting a hot water heater then the exhaust hole diameter is probably 3 inch diameter. If it is 3 inch diameter and you are going up more than 15 feet to the top of your chimney, you must use a 4 inch diameter flexible liner or ridged pipe for proper draft. We also suggest to go ahead and use a 4 inch diameter flexible liner or ridged pipe even if the total length is 15 feet or less.


    Not the depth or any other dimension inside your fireplace.

    Most gas log fireplaces require an 8 inch liner kit or rigid kit. But do not assume that is the case for the gas log fireplace kit you are installing. Obey the requirements for that specific unit that are in your installation/instruction manual.

    THANK YOU FOR ANSWERING THOSE QUESTIONS

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