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vacuumbed's avatar
vacuumbed
Explorer
Feb 03, 2016

Suburban Furnace exterior vent types (with pic)

Hi everyone,
I decided to upgrade my Suburban NT-16S to a new NT-20SQ. The new furnace just came in today.

I noticed that the new vent cap is different. The old one is a heavy duty chrome while the new one is a thin stainless steel type with a lip at the top bent outward. Is there any advantage to the new one?

27 Replies

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  • chuckbear's avatar
    chuckbear
    Explorer
    Feb 05, 2016
    trailrider wrote:
    chuckbear wrote:
    That lip won't keep out more than a drop of rain. It is there to allow the install of a bug shield, which hangs on the lip and is secured by a spring. The difference in length is probably to allow it to fit in the new furnace and not the old one. Chuck


    The lip isn't there to "allow the install of a bug shield." The furnace manufacturers specify in their manuals to never block the exhaust or intake of the furnace with anything, including screens.


    Wow, Most every RV supplier out there, including Amazon must be totally unaware of that, including us and most RV's we have seen.
    http://www.amazon.com/JCJ-M-200-furnace-Outside-Fitting/dp/B0002UHWIG

    Chuck
  • trailrider's avatar
    trailrider
    Explorer
    Feb 04, 2016
    chuckbear wrote:
    That lip won't keep out more than a drop of rain. It is there to allow the install of a bug shield, which hangs on the lip and is secured by a spring. The difference in length is probably to allow it to fit in the new furnace and not the old one. Chuck


    The lip isn't there to "allow the install of a bug shield." The furnace manufacturers specify in their manuals to never block the exhaust or intake of the furnace with anything, including screens.
  • time2roll's avatar
    time2roll
    Nomad
    Feb 04, 2016
    I would go with the old one. Keep the new for a year for if issues should change your mind.
  • Dutch_12078's avatar
    Dutch_12078
    Explorer III
    Feb 04, 2016
    vacuumbed wrote:
    chuckbear wrote:
    That lip won't keep out more than a drop of rain. It is there to allow the install of a bug shield, which hangs on the lip and is secured by a spring. The difference in length is probably to allow it to fit in the new furnace and not the old one. Chuck


    Perhaps I should install the old one.

    The old one functionally has a "lip" as well to keep water runoff from being ingested. I think the full width lip on the new one does a better job of it though, compared to the beveled circular lip on the older style.
  • Chris_Bryant's avatar
    Chris_Bryant
    Explorer II
    Feb 04, 2016
    It's not really for rain as such- it's for the water running down the side of the rig. I would go ahead and install the lip even on the old one- it was pretty common- particularly on Airstream and round bodied coaches.
  • vacuumbed's avatar
    vacuumbed
    Explorer
    Feb 04, 2016
    chuckbear wrote:
    That lip won't keep out more than a drop of rain. It is there to allow the install of a bug shield, which hangs on the lip and is secured by a spring. The difference in length is probably to allow it to fit in the new furnace and not the old one. Chuck


    Perhaps I should install the old one.
  • chuckbear's avatar
    chuckbear
    Explorer
    Feb 04, 2016
    That lip won't keep out more than a drop of rain. It is there to allow the install of a bug shield, which hangs on the lip and is secured by a spring. The difference in length is probably to allow it to fit in the new furnace and not the old one. Chuck
  • tarnold's avatar
    tarnold
    Explorer
    Feb 04, 2016
    The new lip will also help deflect the heat(rising) away from the coach.
  • Chris_Bryant's avatar
    Chris_Bryant
    Explorer II
    Feb 04, 2016
    They sometimes put that lip on the older style as well- I would probably use the new one. To me it looks better- plus less wind resistance while driving :D

    Good point about making sure the overlap is enough on the exhaust tube.
  • trailrider's avatar
    trailrider
    Explorer
    Feb 04, 2016
    I see the exhaust tube is shorter on the new one. Make sure it's long enough to reach the furnace and overlap enough to seal.

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