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Polypropylene venting

Steve_210 Member Posts: 645
Just curious what you guys think of polypropylene A lot cheaper Than stainless steel.

The Lochinvar knight Manuel States for every one foot of flexible pipe you must allow three feet of venting.

And for every one foot of Rigid you must allow 1.6 ft of venting.

Anybody know if the other condensing boilers have similar restrictions.


  • Paul Pollets
    Paul Pollets Member Posts: 3,656

    We've been using PPE for over 3 years and really like it. Most of our installs are Viessmann boilers with no vent length requirements on CFA. The boilers can use either 2" or 3", depending upon application and sizing. The larger mod-cons use 3".

    I'm surprised that a boiler company would have such a requirement for length of the CFA in proportion to the vent length.

    Wonder how many installers will follow the instructions??
  • Steve_210
    Steve_210 Member Posts: 645

    For responding Paul

    Really like the product but the restrictions are tough in our area

    NYC really does not allow Sidewall venting (Must be 4 ft from any openable window)

    In most cases this cannot be achieved.

    Anybody know If other condensing boilers have Same Restrictions
This discussion has been closed.