Gnats in bathroom

[fainttrace]

Hello, I'm new to travel trailers and having issues with gnats in my bathroom and I need some help / suggestions. I just got my new trailer last friday and when I checked on the camper saturday, I immediately noticed gnats in the shower skylight. The black tank is empty and has not been used yet, I covered the shower drain and bathroom sink, and the toilet has water in it. I did check the roof around the skylight and it appears to be sealed.
The camper is in a rural area and is connected to a septic tank but the black and gray valves are closed. Is this type of problem normal? It's currently November and I'm very concerned about having gnats problems in the summer weather.
Any advice and suggestions will be greatly appreciated.
Camper....
2016 Salem Cruise Lite 241QBXL

[Tonylmiller]

First, I would try to discover how they got in there. Pour a glass of water into all of your drains so that they are sealed by the trap. It could be that one pregnant female got in there somehow and laid 500 eggs. You may never solve that one.
Then I would just spray a pesticide and try to kill them. Although, if they have no food inside the (new) camper, I would think they would all die anyway if you have time to wait.

[Flybob]

You are making the assumption that equipment in the RV has not been used. Occasionally dealer employees will have food or use sinks etc while prepping units. Pour 1 gal water down all drains to flush them out and fill traps. Check closets floor for food scraps. Their life span is very short and unless the cause ( food or open trap) persists, they will not come back.

[dieselbobcat]

I find that they are attracted to the light of the skylight. When we get gnats/mosquitos on occasion, the easy to be rid of them is to remove the screen from the bath fan, turn the fan on its highest setting and turn on the light in the bath... shut off all others lights in the camper and leave the bathroom door open for a good hour or so... attracted to the light and without the screen the gnats will be sucked out when attracted to the area... be sure to leave the entry door or a window open to maximize airflow.