Tail Light Condensation

[Rzrbrn]

I have a lot of condensation in the tail lights and marker lights of my new 2019 BigFoot 25RQ. I searched this forum but could not turn up any relevant threads, if there are some please point me to them.

It has been raining since I picked up my new 2019 25RQ on Feb 19. I notice there is condensation in both R and L tail lights as well as in at least one red upper marker light. The TT is under a carport but the wind and rain is so strong it continues to get wet, so I will have to wait for dry weather to take apart the light fixtures.

My plan is to remove the lens by unscrewing from outside the lens: It appears to be square bit screws holding the lens in place. Once off I will dry the bulbs, lens and socket. I will used di electric grease on the bulb connections and reassemble. I plan on using Geocel Proflex RV clear sealant around the edge of the lens and will do this same procedure with the red marker light in the top rear of the TT and any other lights with condensation.

Anyone have any input regarding this plan? Is this a good sealant to use around the tail light? Is dielectric grease ok to use? Am I missing anything?

Should I use Butyl Tape instead of Proflex, or in addition to Proflex?

[k corbin]

Originally Posted by Rzrbrn

I have a lot of condensation in the tail lights and marker lights of my new 2019 BigFoot 25RQ. I searched this forum but could not turn up any relevant threads, if there are some please point me to them.

It has been raining since I picked up my new 2019 25RQ on Feb 19. I notice there is condensation in both R and L tail lights as well as in at least one red upper marker light. The TT is under a carport but the wind and rain is so strong it continues to get wet, so I will have to wait for dry weather to take apart the light fixtures.

My plan is to remove the lens by unscrewing from outside the lens: It appears to be square bit screws holding the lens in place. Once off I will dry the bulbs, lens and socket. I will used di electric grease on the bulb connections and reassemble. I plan on using Geocel Proflex RV clear sealant around the edge of the lens and will do this same procedure with the red marker light in the top rear of the TT and any other lights with condensation.

Anyone have any input regarding this plan? Is this a good sealant to use around the tail light? Is dielectric grease ok to use? Am I missing anything?

Should I use Butyl Tape instead of Proflex, or in addition to Proflex?

New gaskets should not be leaking unless they were improperly installed. You should let the company know about this issue. However this problem can also be created because the tail light is not properly draining at the lower edge. It is inevitable that some moisture will get inside of tail lights so that means it does need a way to exit by gravity. There should be a small weep hole slot that the water can exit from down at the base of the tail light, a little notch coming into the plastic from the back edge.

Just on the off chance that the installer was having a brain fog day do an inspection and make sure he did not get the weep holes facing to the top instead of to the bottom. If the installer did that it certainly would create the situation you are experiencing. Some tail lights have a rather symetrical shape and could get mixed up with the left being installed on the right side. I almost did that mix up myself when I put new tail lights on my Campster. Fortunately I caught my error before I got the wires hooked up and the covers put in place.

[Borrego Dave]

No idea of what your lights look like Henry, but is there an open area on the bottom center edge of the lenses to drain any moisture out? Never had a problem myself if water got inside the lenses and never had one fail from it. Dust buildup on the bulbs were more of a problem for brightness. Possibly there isn't enough butyl tape under the base?

[Rzrbrn]

Thanks I will look for the weep holes.

But it looks to me like I at least need to take the lens off and dry, and lubricate, rather than just assume they will dry out if/when the weep hole are opened. Am I right about this?

[Rzrbrn]

Trying to attach pic of the Bargman tail light;
Did not work trying again

[Rzrbrn]

trying to download pic of lens
Can't download. The tail light appears to be the Bargman 30-84-508 Taillight (Amazon)

[Tim Taylor]

We have a 2011 Casita and left rear tail light was almost full of water. Some of the LED lights were still working. I just ordered and replaced the unit. I kept the old light to try to determine how the moisture got in. It has been sitting on my shelf for three months with no leakage. I have no idea how that water got in there!

[Rzrbrn]

I just got the following email from the President of Bigfoot so I may take it off and dry it out but I am not worried about it as much:


Hi Henry,

The clear lens is just an add on for refraction. It is not part of the sealed assembly. There is no concern or issue with the light. The light behind this cover lens is sealed.

They all do this. Thanks

Grant

[Mike_L]

I've seen this happen before.
The lens should seal to the base of the light and the base should seal to your trailer so that water doesn't leak in. If the lens fills with water, depending on the type of fixture you have, it may also leak into the wall of your unit where the wire exits the siding.
There should be a small weeping hole on the lower side of the lens for drainage. If the lens is installed up-side-down, this hole acts as a means of entry rather than a means of exit for water.
I've seen roof leaks drip down inside walls, along wires and out into light fixtures.
If you take a piece of duct tape longer than your light is wide and attach about half its width to the wall of your unit just above the light and the remainder of the width covering the top of the light, it will shed any water running down the wall of your unit, preventing it from entering the light.
If this works the problem is with the light fixture. The lens is attached up-side-down, the lens to fixture seal is leaking, the fixture to trailer seal is leaking etc.
If the lens floods with the duct tape in place your leak is elsewhere.

[Rzrbrn]

Thanks Mike. I have not detected any water inside. Only condensation in the back up light. According to Grant, President of BigFoot, the back up light has 2 lenses. The first is sealed, and over this a lens whose only purpose is to detract or diffuse light and is not sealed. Therefore there is no concern that the light would be leaking into the trailer.

I also have a marker light in the upper rear of the trailer. That also has condensation.

It is still raining and cold here inn TN. My unit is in a carport but it is still getting wet. When the rains stop I will start taking the lights apart and try to determine if there is a leak or try to reseal the lenses.

I may try to use a liquid gasket. Or maybe butyl rubber tape.

[SteveV]

I wouldn't use clear silicone sealer between the lens & housing. You may not be able to remove the lens w/o breaking it when you need to change a bulb in the future.
Hopefully there is a gasket missing or a blocked condensation drain on these.

[Rzrbrn]

Good Point Steve V