Diagnose And Repair Venting Issues In A Mobile Home Plumbing System

Diagnose and Repair Common Vent Issues in Your Plumbing System

There is a lot more to a mobile home plumbing system than just water lines and drain lines. The ventilation system is vital to a healthy plumbing system. Without a healthy vent system, your home can suffer a variety of annoying problems.

A lot of venting issues are mistakenly thought to be drainage issues in mobile homes but they are absolutely caused by improper or imbalanced venting design.

There are a few venting and drainage issues in mobile homes that can be diagnosed and repaired by the average DIY mobile home owner. This article will help you better understand and diagnose those problems, and hopefully, repair them.

The 3 Parts of a Mobile Home Plumbing System

Every home plumbing system is made up of 3 elements, or systems. All three of these systems work together so a homeowner must understand all three before they can attempt to diagnose any issue.

Water Supply System

Supply lines carry water into and throughout your home. The supply lines, or water lines, need healthy pipes with tight connections (called fittings) that must handle high-pressure water. You turn the handle on a sink and the pressure forces the water out. The more you open the faucet the more water you get. For the hot water, supply lines go through a water heater first. Leaks, pressure, and the water heater cause the most common issues for supply lines.

Leaks around connections is a common concern with supply lines. Frozen water lines is another big problem that manufactured homeowners face. Our article about heat tape will help keep your supply lines from freezing.

Drain – Waste System

A Drain-Waste System flushes away the used wastewater. Drain lines also need healthy pipe and tight fittings that can carry wastewater to the sewer lines or septic tank. It needs the help of gravity and vent lines to keep the correct pressure in the pipe and push sewer smells up and away from the home.

Drain lines are the big (usually white) pipes under a mobile home that go from the water fixtures to the sewer or septic. The pipes are installed at a slope so gravity can push the waste away.

Mobile home plumbing repair rachellhough
Image Source: Rachell Hough

Ventilation System

Yes, all mobile homes have ventilation systems. I’ve seen some articles claim mobile homes didn’t have vents but it’s just another mobile home myth.

A ventilation system is part of the drain-waste system but it’s still considered to be a separate system. Vents do 2 things:

  • maintain pressure in the drain lines and help wastewater to drain smoothly
  • act as a planned route for sewer smells to follow so no one smells the foul odors in the drain waste pipe.

A healthy plumbing system must be able to breathe and it does that via the vents.

The ventilation system allows air to enter your drain lines so it can keep the right atmospheric pressure in the pipe. Without the ability to breath, draining water would create a vacuum or suction that pulls all the water out of the P-traps (at all fixtures and before sewer line connections).

The ventilation system is called several different things: ventilation pipes or ventilation lines, or just vents for short. Vent lines or drain-waste-vents (or DWV) are also used. And they all mean the same thing.

Elements of a Mobile Home Ventilation System

Mobile and manufactured homes typically use 2 kinds of vents in their ventilation system: the direct vent, and the auto vent.

Direct Vents or Vent Stack

The most common kind of vent is called a direct vent also referred to as a vent stack, soil stack, or VTR which is short for ‘vent through the roof.’ You can see these vents coming out of the roof or running up the side of the home where the drain line meets the sewer line (if needed).

These vents tend to get clogged with leaves, bird or bee nests, or any other debris that can find its way into a pipe sticking out of a roof.

Wet Vent

When one pipe serves as both drain pipe and vent pipe it’s called a wet vent. They can save a lot of pipe and money. Plumbing codes vary with these and there are a lot of restrictions.

Wet vents can consist of a toilet and sink or a toilet, sink, and tub (right image below). It could also be the kitchen sink and the laundry sink, whichever is closest.

Auto Vents or Air Admittance Valves

An auto-vent is a small device that is usually placed under sinks to let air into the drain waste line so it can keep the right vacuum or pressure when draining. Auto-vents do not let the air out, only in. We’ll cover them more below.

A lot of plumbers will use auto vents instead of running a wet vent or a direct vent in new home construction and remodels. It’s cheaper because it uses less pipe and quicker because you don’t have to anything but screw an auto vent.

P – Traps

A trap is a curved pipe under your fixtures but you usually only see the traps under your sink. Traps are a part of your ventilation system and they are called a trap because it actually traps water.

There are two main kinds of traps used in a mobile home: P-traps and running traps. There used to be S-traps but those aren’t used anymore.

Traps use water to close, or seal, the drainage-waste pipe so sewer smells in mobile homes don’t occur. The water seal forces the sewer smells to exit out of the roof vent instead of the fixture. Every time you run water it flushes the trap but gravity does its magic to keep some water in the lowest part of the traps.

The Reason Manufactured Homes Have so Many Vent Issues (or Why Plumbers Don’t Like Working on Mobile Homes)

Below you’ll see a photo of some plumbing that has been installed in a new manufactured home being built in a factory. It’s a brand new home with brand new plumbing and seeing it will make a master plumber with 22 years experience chuckle and walk away shaking his head.

Let me make it clear that manufactured homes only have to meet HUD code – no local codes at all. I’m sure everything in the image passes HUD code but sometimes HUD codes need to be, umm, fixed.

In the photo below, you are looking at the backside of the utility room where the washer will go in the manufactured home.

The white box is the washer box. That’s the control center for your washing machine – it’s how you connect the washer to your home’s plumbing system. You tie in the washing machine drain hose into the home’s drain system and attach the water supply lines from there. The water will flow through the p-trap and then down into the drain line. The small black thing on top of the right pipe (to the right of the P-trap) is an auto vent.

What’s Wrong with this Image?

In ‘real’ plumbing, the air vent should always be above the washer box and the washing machine drain lines would be larger to accommodate the very powerful new-age washers we have nowadays. Oh, and it’s always smart to use a real stack vent for your washing machine because that’s a lot of water leaving a large appliance very quickly.

Plumbing and electrical cables in manufactured home wall

Yes, this design will work. It has worked in millions of manufactured homes for many years. However, it’s things like this that ultimately cause an issue and make master plumbers across the nation not want to work on our homes. There’s no easy fix to this once the walls are installed.

It’s things like this that give manufactured homes a stigma they just can’t seem to shake. There are 3 systems that should never be cheaped out on: plumbing, electrical, and HVAC (mobile home heating systems and ACs). Manufactured home builders are well-known to go cheap on all three.

With all that said, let’s learn about the common cause of venting issues issues in mobile homes, how to diagnose an problem, and how to repair it.

5 Common Causes of Mobile Home Venting Issues

Venting issues in mobile homes are usually caused by four things and we’ll cover them all in-depth:

  • The venting pipe sticking out of your roof can get clogged fairly easily
  • Ventilation pipes can become disconnected during transport or settling
  • Auto vents wear out
  • Poor initial design from the factory
  • Many homeowners don’t even realize that plumbing systems have ventilation lines, or pipes, in the first place.

Clogged Vent Stacks

Vent stacks can get clogged by leaves, birds, rodents, and countless other things. To repair this you will need an auger or drain king or a snake. A snake is just a coiled metal rod that twists through the vent lines and either pushes the clogs away of pulls them out. An auger is a high-pressure water hose that pushes the clog down through the drain lines.

You can buy toppers that allow good air flow but keeps things from falling into the pipes. Vents can also get crushed or bent so a regular checkup is recommended to ensure there are no leaks around the seal and that nothing is blocking air flow.

Disconnected Vent Lines

Vent pipes can get damaged by a slew of things. Mostly, though, it’s either transportation or poor installation. Accidental cutting is also common. There are three ways to fix disconnected vent lines: find where the disconnection has occurred (which is difficult), run new vent lines to tie-in to the main stack, or hope it can be cured by an auto vent.

Worn-Out Auto Air-Admittance Valves

Auto vents, or air-admittance valves are mechanical as in they open and close every time you use water. The cheap brands (used by a lot of manufactured home builders) aren’t so great and wear out quickly. Luckily, replacing auto vents is pretty easy.

Poor Design

The fourth most common reason for venting issues in mobile homes is poor design from the factory. See the image above.

The Unknown

Lastly, but not less important, is the fact that many homeowners have no idea there is such a thing as ventilation in a plumbing system. You can’t repair something if you don’t even know it exists.

Learn How to Winterize your Mobile Home Like a Professional

Troubleshooting 6 Common Ventilation Issues in a Mobile Home

These are the most common signs that will clue you into drainage or ventilation issues.

Problem 1: Foul Odors

Smelling foul odors will be a big sign that something is wrong. You shouldn’t smell anything from your plumbing system. It’s designed to keep that very thing from happening. A foul odor can be caused by poor drainage or ventilation issues or septic tank issues. There’s a few things that can cause foul smells but it’s a sure sign that your plumbing system isn’t working properly.

Problem 2: Slow Drainage

Slow waste water drainage is one of the first signs of ventilation issues. It’s also one of the first signs that you have a clog.

Snakes and augers work if you can find the clog.

If you have an auto vent installed and that drain is slow unscrew the auto vent and see if the water drains correctly. If it does, replace the auto-vent. If it’s still draining slow it’s likely a clog or blockage and you can try a snake or auger. If those don’t work you’ll need to call a plumber to use their industrial strength snake. Those things can get a clog out of just about any pipe (except grease).

Problem 3: Gurgling

If you hear gurgling come from your drains you likely have poor drainage caused by ventilation issues. Don’t confuse there noises with noises that occur when you are running water. That’s a whole different animal.

Problem 4: Water Heater Odors

Of course, not all foul odors are caused by venting problems. Foul water odor could be coming from your water heater.

Problem 5: Missing Water in your Toilet

Nope, the dog probably isn’t drinking all the toilet water! If you find your toilet is missing its water you may have either a drainage leak or a ventilation problem.

Problem 6: Air Bubbles in Your Toilet Water

Seeing or hearing bubbles rise from the toilet bowl is another sign that your drainage system isn’t getting enough ventilation.

Read about 5 more common plumbing problems in mobile homes.

Air Admittance Valves

An air admittance valve is used in cases where connecting a drain pipe to a stack vent is difficult or impossible. They ensure that waste goes down to the sewer and gases stay out of your home.

Look under your sinks and see if you see something like this (it could be black or white, straight or domed).

Cheap air admittance valves

Essentially, an air admittance valve acts as a set of lungs for a weakly ventilated drainage system. It allows the pipe to suck in air when needed and closes off when it’s not needed.

How do Air Admittance Valves Work?

Air admittance open and close by gravity. When anything moves along a pipe it essentially seals it and causes a negative air pressure. That negative pressure pushes the valve open so that air can enter the pipe. As the negative pressure eases the valve slowly falls back into place.

How an air admittance valve works
Installing an air admittance valve under a sink

Studor Air Admittance Valves

We highly recommend the Studor brand air admittance vents.

Studor is most plumber’s favorite brand for auto vents or air admittance valves. Joe, the master plumber of the family, always recommends that homeowners replace their original manufactured home’s generic air admittance valve with a Studor brand as soon as you notice signs of failure. He says there is a huge difference between a $5 item and a $35 valve.

(Note: Studor does not pay us for this recommendation. After 22 years as a plumber you tend to learn what works and what doesn’t.)

This video from Studor explains how their air admittance valves work:

How to Install an Air Admittance Valve Under Your Sink

If you notice any of the above signs of drainage or ventilation issues you may want to install or replace an air admittance valve. All you do is unscrew the old one and screw in the new one. If you are installing one where there has never been one it’s a little more work.

The white pipe is drain lines and it is sloped though you may not notice it.

Q & A for Common Mobile Home Plumbing Venting Issues

Question 1 – Backups, Odors, Overflows

I live in a 1987 mobile home. When the washer drains, water will back up into the kitchen sink and the fumes are horrible. Sometimes the water even overflows from the drain onto the laundry room floor. I see no vent stack thru the roof nor do I see any under sink venting devices. What do you suggest to correct this problem?

Answer – 3 Common Issues

You are experiencing three very common plumbing issues but it’s likely caused by one thing – poor or failed venting. It’s kind of a double whammy of not enough (or failed) ventilation and possibly too small of a drain line from the washer.

First, try adding a Studor auto vent under the kitchen sink. That should help the smell. Studor is the best name brand and well worth spending the extra money over the other auto vents.

If your washer drain line is only an inch and a half pipe you may want to consider re-piping it with a two-inch pipe. While doing that, tie it in under the house directly to the main drain/trunk line itself, separate from the kitchen drain. That will definitely fix your problem! Those 1.5″ pipes just aren’t meant to handle a lot of water, especially high-pressure water being released from a newer washer.

Try the auto vent first, especially if there is no stack connected to the immediate system (though there could be one in the walls that has failed – the cheaper vents seem to fail after only a few years)

Questions 2: Drainage Issues in a Mobile Home

I have a 1981 Hallmark 2 bedroom trailer. Our bathroom and kitchen sink won’t drain. The tub and toilet are fine. I’ve taken apart the plumbing under the sinks and ran a snake as far as I could, and still nothing. I’ve crawled all under the trailer, and the only lines I see coming down and connecting to the waste/septic is for the washer (also fine). The trailer is insulated very well underneath, and I’ve cut a couple of spots looking for pipes under the sinks but for the life of me, I can’t find anything lol. I’ve even googled various phrases relating to the plumbing plan, to no avail. Any ideas?

Answer: Blockage or Ventilation Issues

It’s most likely a blockage or ventilation issues. Try a true professional plumber’s snake (those they sell at Lowe’s or Home Depot are not that great and are mostly for sinks, not drainage line blockages. You should be able to rent one. Poor ventilation could be air locking the system as well.

Question 3 – Noises and Sewer Smells in Mobile Homes

I have running water, but I have this horrible stench in the kitchen and it sounds like scratching in my walls first it was on the repair side of the house now alternate on both sides. The odor became so bad 4 days after we had water we left the house after raising 5 windows in the house. I returned the odor comes and goes and I haven’t heard the scratching noises. Please help. Asap

Answer: Open Sewer or Venting Issue

It sounds like you have an open sewer pipe or a ventilation issue. When you had your dishwasher uninstalled did the drain to the dishwasher get capped? Maybe the dishwasher’s drain was accidentally left open. All you’ll need to do is find that and cap it like you did the water lines.

If it’s not an open waste line from the dishwasher it’s possibly a ventilation issue. The noise could be your pipes and that usually means the system isn’t able to breathe properly. You can either look for a broken vent line (poor glue jobs, settling, or accidental cutting are the usual culprits when it comes to disconnected ventilation lines) or you can try installing an under-the-sink Studor vent to act as a mini-vent and help rid your home of the odor but my money is on the dishwasher drain assuming you had none of these issues until the dishwasher was disconnected.

Plumbing is a Complex Topic

It’s difficult to explain venting issues in mobile homes. Plumbing seems simple but it isn’t.

Keep in mind that a licensed plumber is absolutely necessary for your more complex drainage issues in mobile homes. You should call them if you have a serious issue or can’t find a leak (water is one of a mobile home’s biggest enemies). They have ways of testing a system and narrowing down a problem in minutes.

Thank you so much for reading Mobile Home Living®!

Please Note: Your state and local plumbing codes will always determine the exact requirements for your manufactured home’s plumbing system. This article should be used as a reference only. Mobile home venting issues is a problem that requires an on-site inspection and testing most of the time.

This article was first published on Feb 11, 2016. It was completely updated on May 9, 2019.

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  1. Lynn M Carl says

    Hi Mobile Home Living,

    We just put a new insulated roof on an older 1974 mobile home and now we are getting a strong sewage odor inside, but only when it get up to 100 degrees outside! The problem is compounded when we run our new air conditioner unit. Any thoughts?

    1. Crystal Adkins says

      Hi Lynn,

      It sounds like the roofers sealed off your plumbing system’s vent line so the odor has nowhere to go except back into your house. Your roofer should have known better.

      You’ll need to have them fix it asap otherwise you’ll keep getting the smell but more importantly, your plumbing system may start making weird sounds and backflow and neither of those is good. Best of luck!

  2. roger peck says

    i need to work on a 1963 HILTON 12 x 60, mobile home 3 bdr. i am looking for the heat ducting plans

    1. Crystal Adkins says

      Hi Roger,

      In 90% of manufactured homes, there will be a straight duct ran right down the middle of the home with branches off of it. For double wides, there will be 2 trunks, one down the middle of each section. There would be no papers or schematics available – builders didn’t release that kind of stuff very often. Heck, even the manuals are just made per size of the home (one for single wides, one for double wides), and not models.

      These articles may help you: How to Seal Heating Ducts in a Mobile Home to Save Money
      Mobile Home Heating Guide to Furnaces and Heat Pumps
      How to Repair a Mobile Home Belly Board

      Best of luck!

  3. Arlene Perea says

    Hi. My name is Arlene. I live in a 1993 (I believe) Solitaire. I believe I have a venting issue. My master bedroom toilet will not flush properly. Both vents, master and guest, were broken at the roofline last year after snowstorm. Not sure how to repair since breaks are just below (about an inch) propanel roof. Will I have to remove propanel sheets to repair? I also have extremely hard water so that doesn’t help the toilet and fixture issues. Any guidance?

    1. Crystal Adkins says

      Hi Arlene,

      You should be able to install a boot around the roof vent. Height for the vent pipe is important as it helps push the smell up and away from the home but you can work with a shorter one as long as the vent itself is clear of debris. If there are no issues in your tub or sink in the bathroom with the toilet issue it’s probably not the vent and just a regular ole clog in the line. Try using a snake to clear it and see if that works. If not, you may need to call in a pro that has an industrial snake. Best of luck!

    2. BernadetteConrad says

      I have a 79 Emperor what I want to know is can a drain pipe be moved for the washing machine right now it’s in my bathroom and would like to relocate it where the washer is.

      1. Crystal Adkins says

        Hi Bernadette,

        Your washing machine drain pipe can be moved. It will take a little crawling under the home and drilling a new hole for the pipe to come up through your floor. I’d get estimates from at least 3 plumbers and if you have other plumbing issues have them do it all at once. Best of luck!

  4. Angie says

    I’m curious to know: what exactly is meant in this article with “there is a huge difference” between the Studor Air Admittance Vents and the cheap black ones? Are they just superior as far as the material goes? Or do they work differently and lead to better ventilation?

    1. Crystal Adkins says

      Hi Angie,

      They do the same thing but Studor is made better and have less failure rates.

      Every time you use water it has to open and then close, that’s lot of mechanical action so it needs a smooth actuator that Is easily triggered by air fluctuation/suction in the lines (I’m not sure that’s the right name for the part inside).

      I should be a Studor salesperson (or at least an affiliate, huh?) I swear I don’t get a penny! They really are just better.

  5. Fatima says

    I Own 1996 Mobil home
    Bought it a few months ago.
    I hadn’t had a problem with the pipes until today I noticed that the water in the kitchen sink clogged.
    I’m concern bc I was informed that it can be expensive and that the system is not the same as a regular home. Please help!
    Is there anything I can try or do b4 calling a professional?

    1. Crystal Adkins says

      Hi Fatima,

      When its a kitchen sink that is clogged its usually just grease and food. Have you tried a liquid plumber product? If that doesn’t work, try plunging it: Seal up the one side of the sink (assuming it’s a double) with a rag and make sure it’s air tight, then use a sink plunger on the other side. The suction should loosen up your clog a bit.

      You can also buy a cheap snake and try that. The problem with grease is that a snake won’t necessarily cut it because the grease just seals back up as soon as the snake is pulled out.

      In the worse cases you’ll need to pull the p-trap and clean it out. Make sure you install it back properly so there’s no leak.

      Best of luck! Let me know how it goes.

      1. ALISA STALKER says

        I have the same issue with my kitchen sink. And we had a professional plumber snake it twice with no luck. Last night we plunged it forever and it finally worked, ran hot water and boiled water for over 20 minutes. This morning is it clogged again. Any suggestions??

      2. Crystal Adkins says

        Hi Alisa,

        It’s most likely grease that’s closing right back up after the snake is removed. You’ll want to replace the P-trap (and all other pipe with grease in it). You should be able to remove the P-trap and see the grease if it’s in the rest of the line. You can always clean out the p-trap but it’s a messy smelly job and can’t be done at any sink or toilet. It’s well worth $15 to not have to deal with the mess.

        Let me know how it goes!

  6. Janel says

    Artic freeze, two bathroom mobile home , one on each end. One bathroom and kitchen works great, one bathroom is you flush toilet or run bathtub or sink water will poor out of the bottom of the toilet. Shealth was cut under bathroom and water came pooring out. Pipes are thawed and no water running but should I call a plumber, have no shut off valve on anythink.. Help 69 year old retired women in tears.

    1. Crystal Adkins says

      Hi Janel,

      You’ll need to find your cut off valve at your meter but there should be one outside under your home, usually at the corner where the garden hose goes.

      Call you water company and a plumber immediately. You have to stop the water from soaking into your wood. You’ll def need a new toilet ring on that one toilet.

      Best of luck! Let me know how it goes.

      1. Melissa Nichols says

        I couldn’t find a way to start my own comment, so I am hoping you get this in a reply to one of your answers.
        I live in Florida & I believe I have a problem with venting. I had a guy go up on the roof to see if the vent pipe was clogged & to flush & clean it.
        I can’t afford a plumber, so he was just a neighborhood handyman.
        He reported that the stack located between the bathrooms seems to be completely sealed with an aluminum piece that resembled an upside down soup bowl.
        He could find no way to open it, as if it were a cap – that it seemed to be all one piece. He also said there were no holes or slits to allow for air to get in.
        I do have an AAV on one bathroom sink & one on the kitchen sink.
        I was able to remove the cap off the AAV under the bathroom sink. My next goal is to buy a wrench big enough to get the part out that is screwed in & replace it with a new one.
        From searching, I believe that Florida allows for there to be no roof ventilation and that I could possibly just have AAVs under a couple of sinks.
        A friend suggested putting Sure Shot Drain Opener in it, once I get it off.
        I am not sure about that, though.
        I don’t want to go up on the roof myself. The guy said that all the pipes on the roof were similar, so I am not sure what else to try, besides replacing the AAV & hope it starts flushing again.
        Is there a way to test the system, by holding down the spring to let air in & then flushing? Or is it going to be replace & see?
        Or do you have another suggestion for why the roof vents don’t seem to be vents?

      2. Crystal Adkins says

        Hi Melissa,

        My husband and I lived in FL for a couple of years and he worked as a master plumber. FL does allow vent stacks. The vent that is sealed could possibly be for a gas furnace but since you live in FL many people don’t install heating units at all and they would just seal the vent. Think that could be what you’re looking at? Is there another vent that isn’t sealed? See if that one is clogged…
        Let me know!

  7. Lisa says


    I am at a loss. I have had 3 plumbers out for a slow drain in our guest bathroom. 1st plumber says it is my P-Trap, The 2cnd plumber says that our mobile home has a cast iron pipe that is rusted and causing a bad drainage.

    Our mobile home is about 20 years old and our guest bathroom tub is acting up and slowly drains.

    Now the 3rd plumber says it is the air flow and that a part under the house needs to be replaced with a new pipe since it is leaking under the house. This has been stressful and time consuming. I do know that I have been given 2 estimates with 2 different repairs from 2 plumbers. To make a long story short I found out my 2cnd plumber didn’t tell the truth and it is all black pvc pipe under the house. So if it is the air flow system is it best to just replace the air flow vent or do a total repair of the tub, pipes and to add a access door behind the tub to prevent this from happening again? I have a repair estimate at 1600 or total tub , pipe repair at 3600 🙁

    Lost and confused!

    1. Crystal Adkins says

      Hi Lisa!

      I’m so sorry you’re having so much trouble. It sounds like you have a partial blockage under the guest bathroom and those estimates are way too high in our opinion. If you have an auto vent under your sink in that bathroom take it off and see if the drain is faster. If it is, you’ll know it’s the vent. If not, it’s a blockage. A snake can fix the blockage (industrial strength) in no time.

      Beast of luck!

  8. Emily Chaney says

    I live in a 1997 double wide 3 BDRM 2 bath Palm Harbor home. Everything works great except the bathroom sink that is the farthest away from the water supply. We have no water at the sink. Tub & toilet are fine. I had to repair the line which required pulling the pipe up about 1″ from under the house. I though the problem might be from the water having to go “uphill” a little more than before, so I added a small amount of pipe & dropped the line back down to where it was. Still no water. There is a vent under the sink & like I said, the tub & toilet ( & rest of the house) get water & drain water fine. Any ideas of what to do or try?

    1. Crystal Adkins says

      Hey Emily,

      Assuming there is no leaks under the home, I’d suggest changing out your aerator (the screen at the tip of your faucet). When you moved the lines around You probably loosened up some gunk and it’s closed off your faucet. Just unscrew it from the faucet and see if you have water. You can buy a new one for a couple of dollars or just clean the old one.

      If that doesn’t work let me know (but def make sure you don’t have any water under your home).

      Best of luck!

  9. diane bynum says

    Hi! I just bought a singlewide 1979 Liberty mobile home in Florida. The bathroom floor is soft in front of the sink. We live in N.J. and won’t be able to even visit this home for a few months. Should we have the water shut off until we get there? Thank You!!!

    1. Crystal Adkins says

      Yes! It’s probably a good idea. No sense in taking the chance of leaks until you get there.

  10. Wendy says

    I have an AAV under the kitchen sink and would like to know if the pipe can be cleaned out? I can see gunk in the line. We also hear gurgling from the kitchen sink while doing laundry.

    1. Crystal Adkins says

      Hi Wendy,


  11. Frank Mendoza says

    I live in an early ’80s mobile home and all the sinks and the tub drain fine. When flushing the toilet, it drains very slow and there’s a gurgling sound coming from the tub and well as horrible gas smells from both the tub and the kitchen. Since all the other sinks drains fine, if the toilet the only one suffering from poor ventilation?

    1. Crystal Adkins says

      Hi Frank,

      This sounds like the trunk line is clogged and holding water so the sinks drain fine because it’s not a whole lot of water at once. When you flush, it puts out 1.6 gallons at once which fills everything up and closes off the vents. You’re gonna need a plumber to go in and jet the line. The plumber would know where to go in without blowing out your connections. You could try snaking it yourself but this is pretty big since it’s sucking both traps dry.

      Best of luck!

  12. Kay says

    I have a 1997 (I think) Heartland double wide. The problem we are having is the master bathroom toilet doesn’t flush. At first it would fill up very slow and we could flush maybe 2 times a day. Then it wouldn’t fill up at all. To top it off the master stall shower fills up. It actually clogged up pretty bad yesterday that after showering (5am) the next day (5am) the water was still in the shower. Now, to my knowledge the tub is fine. (We hardly use it) Are we having a main pipe line issue or is it something greater? The 2nd bathroom toilet is fine. It was having the same problem at first but I think now it flushes every time. I just want to know if there is anything we can do to prevent damage and save money. Thank you

    1. Crystal Adkins says

      Hi Kay,

      Yeah, your trunk line is clogged and needs to be jetted out. It would only affect the one bathroom because the other connects to the main trunk at a different place. You could try snaking your line out yourself before calling a plumber but to be honest, paying a plumber for an hour to use their jet and make sure nothing gets blown out is worth that added expense. Best of luck!

  13. Beth Bishop says

    I have a minor to moderate leak that I believe is coming from the kitchen drain, which is located at about the center of my mobile home (island sink, dishwasher, etc.). I first noticed creaking sounds through the floor in front of the sink area, then recently noticed a wet area of ground at the back of the home. Looking underneath the home, the underbelly appears to be bulging only at the most rear area and feels real heavy. My home slants in that direction, so I’m thinking the leak is running there and gathering until reaching a certain point or pressure. My question is, should I create a small drain hole of sorts where the water seems to be gathering until I can get an inspection and repairs done?

    1. Crystal Adkins says

      Hi Beth,

      Yes, you will want to do whatever you can to get the water away from the home as quickly as possible. You can always tape over the holes you make in the plastic. You will definitely want to get that leak fixed. The longer it goes the more damage you will need to repair, especially with the subfloor and cabinetry. If it were me I would cut the water off to the kitchen (assuming there’s a cutoff valve) and only turn it on when absolutely necessary until it gets repaired.

      Best of luck!

  14. betty infinger says

    I have a 1994 mobile home–my washing machine always overflows when washing clothes..Could my septic tank be full or is it clogged up..I have used several drain openers –sometimes helps.. can we separate the washing water hose and let it drain outside in the yard instead of going into septic tank..We live in country..

    1. Crystal Adkins says

      Hi Betty,

      I know I’ve answered this comment before but my commenting system in on the fritz so I’m answering it again, sorry. You can open-site your washer line in many areas but it is illegal in many areas, too. You can drain it into a flower bed (and use friendly detergents) you have the prettiest flower bed in the area!

      Best of luck!

      1. BETTY INFINGER says

        Hi. I guess I was asking about this washing machine drain line–it overflows constantly–no other areas back up..when washing clothes it gurgles–when water going down drain–I have used several chemical drain openers–doesn’t help…what do i need to do?? It seems like other things like the sink or bathtubs would be having draining back up problems but we don’t..Does the drain line under trailor need cleaning out? Can you recommend a drain opener that might work??

      2. Crystal Adkins says

        Hi Betty!!

        You need a bigger drain line. Mobile homes are notorious for only having 1.5” drain lines from washing machines to trunk. New machines are powerful and higher-efficiency and needs at least 2” drain lines.

        That will fix you right up! Best of luck!

  15. Jimmie Janel Wright says

    great info thanks

  16. Sue says

    We live in a double wide mobile and recently had a plumbing issue where the water backed up to the tub and toilet and onto the floor. We called a plumber and they unclogged it, saying the water was not draining out to the septic but draining backwards because the pipes in the back end of the mobile were lower than the front of the house. How are these pipes strapped up to get proper drainage. The plumbers want 1700.00 to do it. How can we do it ourselves?

    1. Crystal Adkins says

      Hi Sue,

      I sent you an email. Please let me know if you didn’t get it. Thanks!

  17. Dave says

    Reading this article and the comments makes me want to install a composting toilet. This is nasty stuff. Like, umm, literally.

    1. Crystal Adkins says

      HA! I’ve seen those composting toilets in action and they are pretty cool. Plumbing isn’t too bad – it kinda amazes me how it works together.
      Thanks for reading MHL!

  18. Laura says

    Hi we had water leaking from under our mobile home outside that has a bit of a sewer smell to it. It stopped leaking after about an hour and was leaking out from the area where our washer is located just inside but we cant figure out what is going on. We had to plunge both of our toilets a week before this but other wise we have no pluming issues inside, no leaking inside and no odor inside. We do have city sewer and we had workers from our gas company out working throughout our mobile home park cutting large holes in our roads and cleaning out pipes etc. Our issues all started happening around the same time so we just cant figure this out any input would be greatly appreciated! Thank You!

    1. Crystal Adkins says

      Hi Laura,
      I know I’ve answered this comment before but my commenting system in on the fritz so I’m answering it again, sorry. So, it sounds like sediment from the construction has caused a stoppage somewhere. You’ll need to find it and get snaked out to open flow again. Pipes have a lot of gunk and movement will stir it up.

      Best of luck!

  19. stanley robinson says

    we are re-plumbing our fortune home manuf. #02fo ve 286405s, ser no.fhin101559ra-8. is it possible to obtain a plumbing diagram for this home.

    1. Crystal Adkins says

      Hi Stanley,

      Probably not. The industry doesn’t seem to want to make their schematics available from older models. You may luck up and find an owner that has scanned in their manual or brochures but that’s about all. I’ve never heard of a single success story of any owners getting help from a builder regarding older models, unfortunately.

      best of luck!

  20. Alisha says

    I am having issues with my washer not filling right or spinning and draining. Its brand new washer. We live in an trailer park. My mom lives in the same one has the same issues. Also theres has been an lot of rain here.

    1. Crystal Adkins says

      Hi Alisha,

      This sounds like the washer is having issues, not a plumbing issues. Is it filing up slowly or gurgling?

  21. Kimberly says

    We have a 1975 double wide. Just fully renovated the only bathroom. The new bathtub is lower than the old tub which seemed to sit up higher and the plumber put in an overflow which the previous tub didn’t have. Tub drains fine when showering, if dumping a bunch of water, it is slightly slower to drain. I used draino thinking maybe there was a clog but like i said seems to drain fine. When you shut the water off after a shower, the water stops and sits in the drain right at the cross piece the stopper screws into. Soap suds also. I have never seen water sit in any drain like that before. The plumber had mentioned the stack behind the wall is higher than i should be but left it and now is saying the drain is fine with water sitting there. Am i crazy thinking that is NOT normal?

    1. Crystal Adkins says

      Hi Kimberly,

      So, what you are experiencing is due to weir on your P-trap (I don’t know how to explain this so bare with me). It’s normal for the situation you have – the water you see is the same level as your drain. Only way to fix it would be to lower where your t ties into the drain but it’s not a big deal at all.


  22. pat says

    I have a problem with the main bathroom. I have repaired the commode with a new wax ring because the water was running out the bottom in the front. Before this our shower was not draining and the commode would not flush well also we have a bathtub in the same room. I checked the sink in this bathroom and it seemed to be about half stopped up as well. We have a vent underneath the sink and I was going to check the air vent for a clog but they have glued the plug. I have also run snakes and to no avail. Lowes said to put ridx down it and that only made it worse, now the ridx is clumped as well any suggestions.

    1. Crystal Adkins says

      Hi Pat,

      You’ve done just about everything you can so at this point, you really need to call a plumber. You have a clog somewhere but it’s probably going to require a professional snake (RT66). Best of luck!

  23. Johnny Applewhite says

    I have an 80′ double wide. The sinks, tub, shower, toilets and washer on the east end drain perfect. The kitchen sink is in the middle of the house. When you run water into it, it backs up into the tub in the west end of the house. Sometimes the kitchen sink will back up for a few hours. Nothing in the bathroom on the west end will drain. When it drains, it might take days. I have ran a snake from the kitchen sink vent over 50′ east towards the septic tank and i found nothing. The snake stopped but it probably hit the tank wall as the tank is only 10′ from the east end of the house. you would think that the problem was between the kitchen sink and the septic tank but I have found nothing. My next guess is to pull the toilet in the west end and run a snake towards the kitchen sink. Any suggestions?I

    1. Crystal Adkins says

      Hi Johnny,

      Usually, with kitchen sinks, it will always be a grease problem. When you use a ‘regular’ snake the grease just closes right back together as soon as the snake is pulled out (I don’t know the scientific term but the snake goes through the grease easily, but it doesn’t break it up). A professional water snake may be needed to break up the grease and push it down the drain to the tank.

      Best of luck!

  24. Angela Serocki says

    Good Afternoon we have a 2007 Manor Hill 4428-21 Select, 54MAH28443BH07A home. We’ve had numerous issues with the home. We were promised that the homes are constructed so we would not have to worry about water pipes freezing in our MN winters. We are on frost piers. The first winter and every winter since, the pipes have froze. Year one Harvest Homes did come out and determine that the water line was touching a beam which they said was causing the pipes to freeze. They said the moved it. It did not fix the issue. The second year, we purchased and added additional insulation behind the skirting to help eliminate the cold from especially the south wind, but completely around the home. This also yielded no results. Sometimes we can get up in the morning run the water for 5 minutes and 15 minutes later the lines are frozen. The only relief we have found is if we can bank snow up to the bottom of the window seals then the pipes stay thawed. What can we do to fix this issue…we are stumped.

    1. Crystal Adkins says

      Hi Angela,

      It really sounds like your problem is in the ground or the area between the ground and the home. Most manufactured home builders will only cover the pipes from the home’s connection point so I’m impressed with them moving the line from the beam as it’s outside the home. You will need to make sure your water supply line or trunk is below the frost line from the meter to the home and then the vertical line entering the home is very well insulated. Using heat tape in that area is common in your state, too. You may want to call a plumber and have them make sure that trunk is at the right depth and that the area from trunk to home is properly insulated.

      Best of luck!

  25. Kathy says

    I have a 1991 Victorian mobile home, and just recently started to hear a vibrating noise right behind the wall that encloses the shower plumbing after flushing the toilet. By the way, this started during the cold weather, Dec. of 2017. Could you please advise? Thanks so much!

    1. Crystal Adkins says

      Hi Kathy,

      Vibrating could be either partially clogged vent or a loose water line vibrating. This is probably best handled by a licensed plumber.

      Best of luck!