I know this is a common problem, and we have spent hours scouring the forums reading/eliminating causes for smell. Because we haven't found the cause yet, I'm hoping to elicit opinions in case we've missed something that hasn't been tried. We purchased our new fifth wheel 2015 Sundance 2880RLT in June. We have been living full time in it ever since on full hookups. We took a week long trip to FL the last week in July. We left our RV hooked up for that week with the gray tanks open (we had the tanks open approximately 2 weeks prior to leaving). When we came back from vacation, we noticed a slight to moderate sewer smell coming from the toilet after flushing and from the sink when you turned on the water (mainly the cold tap). This smell has continued and we cannot find the cause. We have 2 gray tanks and a black tank. The kitcken sink/tank does not smell. The shower does not smell and it is hooked up to the bathroom gray tank. When we came back from vacation, we immediately closed our gray tanks thinking that would solve the issue. It didn't. We have cleaned the tanks throughly with the flush several times, used chemicals, checked the roof vent and AAV under the kitchen sink, changed our water filters, and checked the P trap. We have water in the toilet and P trap. There is not an AAV directly under the bathroom sink to check. If the coach has one, it is within a wall separating the bathroom and bedroom without access. We believe the pipe under the sink goes into that wall and connects to the roof vent. My husband checked the roof vent yesterday and he thought that it was pretty well sealed between the pipe and the roof. However when he took the top off and looked around to clean the inside and put it back on, you could clearly smell the good smelling chemicals (orange and lemon) from the tanks on the OUTSIDE of the coach, which we haven't been able to smell before. However, when you ran the water and flushed the toilet, it smelled of sewage and not the good smelling chemicals. We have smelled the smell when the fan and AC have and have not been on so we can't figure it out. Any thoughts/suggestions? It just started after vacation (about 2 weeks now) so we don't know what's going on.
Sewer smell bath toilet/sink
- Thread starter lynds876
- Start date
Garypowell
Well-known member
There is a vacuum breaker valve under your bathroom sink. They commonly leak giving the smell you seem to be having. Nothing comparable on the toilet but it might just be coming from the same place.
I simply removed mine and capped the 1 1/2 inch line. You can seal it off with plastic wrap to see if smell goes away.
There is one under kitchen sink too.
I simply removed mine and capped the 1 1/2 inch line. You can seal it off with plastic wrap to see if smell goes away.
There is one under kitchen sink too.
We did both already.
- - - Updated - - -
Here is the plumbing underneath our bathroom sink. We believe the pipe leading into the wall goes to the roof vent.So we sealed around the vent pipes up on the roof to make sure they weren't leaking into the attic and then we tightened the washer cap all the way down. I did dishes and drained the kitchen sink and now the whole camper smells of sewage. We will cap off the kitchen AAV now but we have no idea why this is turning to a sudden strong problem.
jmgratz
Original Owners Club Member
You said you left the grey tank valves open. Close them and see if the smell goes away. When you leave the grey tanks open sewer smells can "back up" into the coach. Remember you have holding tanks not septic tanks. When you leave the grey tank open any food debris that goes into the galley tank might not be flushed out and will sit in the tank and rot causing an odor worse than the black tank. If you wait till the gray tank is full you can cause any debris to flow out of the tank with the water. Also you should flush the gray tank to keep it clean. Also be sure to use some sort of agent to keep the tank clean such as a commercially available tank additive or something like Dawn soap.
We we closed the gray tanks about 2 weeks ago when we returned from vacation and noticed the smell then. We thought that was the culprit but it is not. We intend to use the Calgon, bleach, and dish detergent method tomorrow and we are purchasing cyclone vents for the roof. We capped the AAV in the kitchen. The smell dissipated. We flushed the toilet again and the smell returned mildly. No smell from the bath sink. We are hoping that some of these things will help the situation.
rxbristol
Well-known member
Isn't this what p-traps are designed for? This is what a normal houses have and is the only thing that keeps sewer gases out of the house from the main sewer lines.
jmgratz
Original Owners Club Member
Yes that is what P traps are for but you RV is not a normal house. The RV has a holding tank and you sewer line in your house runs into the sewer or septic tank. Two different systems. With the holding tank any debris that does not flow out will remain in the holding tank and rot.
danemayer
Well-known member
If your sewer hose is supported, you can form a kind of p-trap by allowing it to droop in-between the outlet and the support. Then you can run with gray valves open and not be exposed to sewer gas coming back into the RV.
Some people argue that in an RV park, there are peak periods where the pressure of everything going into the park sewer system can force gas back into your rig and perhaps through your p-traps.
Some people argue that in an RV park, there are peak periods where the pressure of everything going into the park sewer system can force gas back into your rig and perhaps through your p-traps.
farside291
Well-known member
We have the same problem when we leave the RV for 3 or 4 days and its very hot outside. Usually running water down the drain for a couple of minutes will stop the smell and doing the same with the toilet putting water back in the tank to cover the bottom of the tank. I also turn on the vents for a little while to pull the smells out. Forming a makeshift P trap out of the sewer hose is genius and I will do that for now on. I covered all of my vacuum breaker valves with plastic bags and ties. Still periodically get smells but not as frequent.
Does anyone happen to have a picture of what their correctly vented roof vents look like? We thought ours were fine when we looked at them. Not loose, but the pipe ended below the bottom part of the cap that goes over the pipe. So if you can envision what I'm trying to explain, when my husband removed the top portion of the cap on the vent, the pipe was about 1/2" below the bottom portion of what I'm calling the cap over the pipe. We believed that this was alright as it was above the roof, however last night when I was purusing the forums for additional solutions, someone posted a couple of pictures that looked just like ours that were "wrong" and then the correct version of the vent pipe stuck out above the bottom portion of the cap but below the top portion that would have been what my husband removed. I'm not around to take pictures of ours currently, but can anyone understand what I'm saying or trying to explain? I'll try to find the other pictures and post those. The post that I was viewing was several years old.
Lou_and_Bette
Well-known member
Lippert makes a very good vent pipe cover that I had to shorten the amount of vent pipe sticking above the roof, so may be a solution for your short pipe. These new vent covers really work well and reduce odors. Another thing to check, I had an odor problem and finally pulled the plumbing apart and found quite a lot of stinky things clinging to the sides of the pipes through out. Cleaned pipes well with soap and hot water and smell was gone.
campr-pete
Member
We just had the same thing happen to us 2 weeks ago, the water in the hot water heater was awful smelling almost sewer smelling, I let it run for 30 minutes or so with no relief I had to remove the drain plug in the hot water heater and refill still had a slight odor so I removed the water hose feeding the camper, drained it added 3oz of bleach and some calgon dish washing liquid ran only the hot water through all of the faucets,drained the hot water heater once more and everything was fine. From experience anytime you use bleach which is extremely corrosive you should drain and flush. It will destroy rubber,metal and make waste valves very hard to use.
Similar threads
