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Lippert 360 Siphon RV Vent Cap for Black Water Holding Tanks - 4-1/2" Diameter - White
Lippert

Lippert 360 Siphon RV Vent Cap for Black Water Holding Tanks - 4-1/2" Diameter - White

Part Number: LC389381
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$36.88
Retail:$42.43
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This vent cap creates a vacuum to remove odors and gasses from your holding tank and prevent them from entering your RV or camper. Maintenance-free cap has 2 installation options. Fits 1-1/4", 1-1/2", and 2" diameter pipe stacks. Great Prices for the best rv vents and fans from Lippert. Lippert 360 Siphon RV Vent Cap for Black Water Holding Tanks - 4-1/2" Diameter - White part number LC389381 can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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  • Reviews (19)
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  • Videos (1)
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Lippert RV Vents and Fans - LC389381

  • Plumbing Vent
  • Roof Vent
  • Vent Cap
  • 4-1/2 Inch Diameter
  • White
  • Lippert
  • Plastic

This vent cap creates a vacuum to remove odors and gasses from your holding tank and prevent them from entering your RV or camper. Maintenance-free cap has 2 installation options. Fits 1-1/4", 1-1/2", and 2" diameter pipe stacks.


Features:

  • Vent cap removes odors and gasses from the black water holding tank in your RV or camper
    • Prevents those odors and gasses from seeping into the RV
  • Siphoning, maintenance-free design uses the air outside your RV to create a natural, upward vacuum in the vent pipe
    • Operates immediately during any wind condition
    • Eliminates the need to use additives, chemicals, or perfumed cover-ups
  • Integrated bug screen helps keep out insects and debris
  • Durable, UV-resistant polycarbonate construction
  • 2 Easy installation options
    • Modified installation upgrades the lid of your existing vent cap
    • Complete installation replaces your entire existing vent cap unit
  • Universal design is compatible with 1-1/4", 1-1/2", and 2" diameter pipe stacks
    • PVC adapter sleeve (not included) may be needed for 1-1/4" and 2" pipe stacks
    • Funnel is included for 1-1/2" pipe stacks
  • Sealant or an adhesive (sold separately) is required
  • White color
  • Base is RVIA 1192 compliant


Specs:

  • Overall dimensions: 4-1/2" diameter x 3" tall
  • Mounting hole spacing:
    • Side by side: 2-7/16"
    • Across: 3-7/16"
  • Collar diameter: 3-1/2"
  • 1-Year warranty


360 Siphon RV Vent Cap Dimensional Diagram

360 Siphon Vent Cap vs. Other Vent Caps

Dealing with a black water holding tank is something every RV enthusiast dreads, especially if the tank starts to affect the air quality of the RVs interior. Most vent caps cannot perform effectively with wind turbulence - the wind will be forced down into the tank, which will increase the air pressure in comparison to the air pressure in the RV. This drops the oxygen levels in the black water tank and pushes odors and gasses past toilet seals, causing them to seep into your RV living space.


How 360 Siphon RV Vent Cap Works

The 360 Siphon will successfully and immediately eliminate these odors from your black water holding tank in any wind condition. When wind passes over the cap, it is designed to naturally create an upward vacuum in your vent pipe to exhaust any smells or gasses out of the holding tank to the outside of the RV. This drops the air pressure in your holding tank and prevents those smells from getting into the interior of your RV. By doing this, the 360 Siphon has created an oxygen-rich environment that helps further waste breakdown in the holding tank. Furthermore, the 360 Siphon provides you with a dependable, long-lasting solution, whereas perfumed chemicals can take up to 48 hours to kick in and merely mask the odors for a short period of time.


2 Installation Options

This maintenance-free vent cap is compatible with 1-1/4", 1-1/2", and 2" pipe stacks. If you have a 1-1/2" pipe stack, the included funnel is required for installation. If you have a 1-1/4" or 2" pipe stack, a PVC adapter sleeve (not included) may be required for installation. There are 2 options for installing this vent cap: modified and complete. Which option you go with depends on the current condition of your existing vent base and sealant.


If your existing base and sealant have been installed properly and are in good working condition, it is recommended to go with the modified installation. For the modified installation, you will first remove the lid of the existing vent cap. Then attach the funnel, if needed, to the 360 Siphon lid, and attach the 360 Siphon lid to the existing base with sealant (sold separately). You will also need to use the included collar to ensure a proper seal between the stack and base.


On the other hand, if your existing vent cap has UV damage or if it's not installed properly, it would be best to do a complete installation. To do that, you would remove the entire existing cap, including the base. Then you would install the new base with sealant and your existing hardware. Lastly, attach the funnel, if needed, to the lid, and attach the lid to the base with sealant. Please note that the collar is not needed for the complete installation.



389381 Lippert Components (LCI) 360 Siphon RV Plumbing Vent Cap for Motorhomes - White

Replaces Lippert Components 364466





Video of Lippert 360 Siphon RV Vent Cap for Black Water Holding Tanks - 4-1/2" Diameter - White

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.




Video Transcript for The Low-Down on the Lippert 360 Siphon RV Vent Cap for Black Water Holding Tanks

Today, we're gonna take a look Lippert Component's 360 siphoning RV holding tank vent cap. This comes in white. Basically, this is gonna help to eliminate any nasty odors that occur in your RV from that black water tank. A lot of times they can be a build up of gases inside that black water tank that come out of your commode, so this is going to help to siphon those out.Basically, it's going to create a vacuum to pull those gases up and out, and eliminate any of that backtracking gas. It's also gonna create a more oxygen rich environment inside your tank, which is going to help to make that waste break down faster, and that's also gonna have an added benefit of eliminating the need for as many chemicals inside your tank to do that job.It's gonna be a pretty easy install, no moving parts in this setup. It's going to pretty much be effective immediately as soon as you install it.

Just needs a little wind to blow through there through the top of your vent.We are going to have our funnel there to fit into an inch and a half pipe, which is a pretty typical size for your RV roof vent. If you have a two inch pipe you wouldn't need to use this component. The pipe will just fit in there directly.We also have a small adapter ring if you're using this on a taller pipe, or a different setup. There's a complete list of instructions on how to get this installed if you're just updating your old cap, or if you're putting it in a new system, or maybe replacing a damaged, or improperly installed cap.There's also a pretty good diagram there showing just how the 360 Siphon works. This is made of a strong polycarbonate construction.

It's also going to have a built in bug screen, as you can see there, to keep out any unwanted pests from getting into your tank and causing problems there.There's no maintenance required with this, and again, it does come in white. There's also a black version available. That part number is available here at etrailer.com, and it's going to be L-C-3-8-9-3-8-0.That's gonna do it for our look at the Lippert Component's 360 Siphon RV holding tank vent cap in white.

Customer Satisfaction Score:


Customer Reviews

Lippert 360 Siphon RV Vent Cap for Black Water Holding Tanks - 4-1/2" Diameter - White - LC389381

Average Customer Rating:  4.7 out of 5 stars   (19 Customer Reviews)

This vent cap creates a vacuum to remove odors and gasses from your holding tank and prevent them from entering your RV or camper. Maintenance-free cap has 2 installation options. Fits 1-1/4", 1-1/2", and 2" diameter pipe stacks.

by:

Good directions and easy to install.



by:

Well, it was a needed part, since I lost one during hurricane Ian. I ordered it and received it very quickly, and it looks like as good as new. Thank you goes out to you and your staff for helping me with this. I will buy from you again whenever I need to do work on my RV.



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I would give this 5 stars, but it is difficult to install and special sealant required on inside components and piping whereas other vents only require regular rv outside sealant such as butyl tape, eternabond tape and self leveling sealant . It would be helpful if this was included in the product description on the website instead of "Sealant or an adhesive (sold separately) is required" . We as rv owners already know that sealant is required, but 3m 5200, or Sikaflex 221 is specifically mentioned in the instructions which can't be read until the carton is irreversibly opened. These are not normal sealants on hand. Job is done waiting for results.



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I purchased this to replace the original vent on my Winnebago that was built in 1999. It went on easily and works well. I received fast shipping and great service from etrailer.



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Very please I went with this vent.



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Works great, no problems



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Fits over my old mounts so I didn’t have to mount the new bases.



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Just installed and the directions were clear. Easy to do. Definitely a superior design over the old one. At the very minimum you can see the insects nest and easily clean.



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Great Service very fast



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See what our Experts say about this Lippert RV Vents and Fans

  • Diameter of the Base on the Lippert Components 360 Siphon RV Holding Tank Vent Cap LC389381
    The roof vent on your trailer is most likely for black water tank. The Lippert Components 360 Siphon RV Holding Tank Vent Cap part # LC389381 has a base with a 4" outer diameter. The holes most likely won't line up with your existing roof vent but you can drill new ones, jut make sure to seal everything up with part # 34427034145-1. The Lippert Components 360 Siphon RV Holding Tank Vent Cap is designed for a 1-1/2" or 2" diameter vent stack which is a standard size so as long as this is...
    view full answer...
    Image 1 for
  • Difference Between The Lippert 360 RV Siphon Vents # LC389381 And # LC389380
    The Lippert 360 Siphon RV Vent Cap for Black Water Holding Tanks # LC389380 and # LC389381 are the exact same thing, just different colors. If you plan on replacing your siphon vent(s) then you'll also want to use some butyl tape # AL33FJ and some self-leveling sealant # AL98KV to ensure a watertight seal.
    view full answer...
  • Air Conditioner Covers and Sewer Vent Cover To Keep Insects Out While In Storage
    Here is a list of the air conditioner storage covers we carry. I have included all the measurements so you can select the correct cover depending on the height of your units as well. 37" long x 26" wide x 13-1/2" tall # 290-3026 43-3/4" long x 29" wide x 14" tall # 290-3023 39" long x 25" wide x 11" tall # 290-3016 41-1/4" long x 22-1/4" wide x 13-1/4" tall # 290-3024 41" long x 25" wide x 9" tall # 290-3025 34" long x 29-1/2" wide x 14-3/4" tall # 290-3021 35" long x 27" wide x 13" tall...
    view full answer...
  • Replacement Lippert 360 Siphon Vent
    Thanks for the pictures! Sorry but the Lippert 360 Siphon RV Vent Cap for Black Water Holding Tanks item # LC389381 does not come in individual pieces. We do have it in black though item # LC389380.
    view full answer...

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Info for this part was:

Employee Leah B
Updated by:
Leah B
Employee Halie H
Updated by:
Halie H
Employee Kathleen M
Installed by:
Kathleen M
Employee David F
Installed by:
David F
Employee Dustin K
Video by:
Dustin K
Employee Mary K
Written by:
Mary K
Employee Amanda M
Edited by:
Amanda M

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