We got our first LQ trailer and use it most every weekend to go to shows.  During the week it sits outside, closed up and it really seems to get musty, hot, humid, stuffy inside....just like anyplace gets that is closed up in 90 degree summer weather.  After each weekend we do a good job of cleaning out dirty cloths, dumping trash, and get things put away but when we open things up on Friday night to start packing for the weekend shows we climb into a stuffy, humid, still LQ.  It would be nice to be able to leave a window open to get a little fresh air moving though during the week but any rain would wet the inside.  Any tips or tricks to keep the LQ a little more fresh?

Can you leave one of you vents partially open? If you have a walk through door, leave it open along with some stall windows. If you leave power on, a dehumidifier will keep the humidity down, but increase the inside heat temps.

Your only real recourse is to provide an airflow. They make vent covers that are affixed to the roof, covering a vent. The vent can then be left open without the fear of water damage inside. They look something similar to an air conditioner shroud.

http://www.pplmotorhomes.com/parts/rv-vents/rv-vent-covers.htm

We keep ours shut tight and the fridge doors wide open when not in use.  I keep all the shades drawn to keep the light out.  Cabinet doors open under the sink and fridge while she sits.

Yupper she gets hot.  I have a few of those closet air fresheners hidden about.  but otherwise when it comes time I go in and turn on the fridge and she doesn't get opened up until we arrive.

I really do not have any musty smells. You may have water getting in someplace.   You can check your water connections for leaks I found my hw tank and shower and loosened up this year and needed gentle snugs.  Also check you windows and make sure the weep holes are working properly (Use a hose) if not, high pressure from the outside will blast the crud out of the holes and open them up.  (Another lesson we just learned, pollen clog I suspected).  We always open the faucetts after the water presure has been removed just to take the stress of the lines.

I keep a gallon of diluted Mr Clean when we arrive home I add a few cupfuls to the drains to fill the traps and to the toilet bowl.  This helps to keep the flies from coming thru into the LQ while it sits.  And smells fresh too :)

When the water evaporates out of the sink drain it will allow the "VAPORS" from the holding tanks to enter the LQ. That Mr. Clean or either Pine Sol works good.

 We now keep ours in the barn with some of the trailer windows open. Last Wednesday it was 103 outside in the sun, it was 83 inside the trailer with several windows open while parked in the barn with all the barn doors open.

We use "Damp-rid"  it's a chemical dehumidifier.  Nothing more than flakes of calcium chloride.  I pour the used solution on the gravel road for dust control.  Also helps keep the mold from the tack.

The Damp Rid will really help,also,there is a product called Fresh Air (I think) that you can leave open and it leaves a nice scent.I'll have to double check on the name and who makes it.

We installed a MAXX Air vent fan in the bathroom where the crankup was and it was the best investment we've ever made.We leave it open and when we are going to get in the trailer to prepare for a trip,we turn on the reverse and it will exhaust the stale hot air in a matter of a minute or two.It's pricey but it is what they install on the pusher RV's and it is the best.

 http://www.maxxair.com/

Maxair vents are the best and easiest way to solve your problem.  You can get them with or without a fan.  You can keep the vent open year round if you like.  The fan can be set up to suck air our or blow air down.  Any good RV dealer and/or service center will have them.  If your LQ was converted right, their should be power run near the vent already, so that will make it easier for a do it your self job to.

Then why doesn't it eat the plastic bottle that it comes in? Why hasn't our Coleman "port-a-pottie" black water holding tank as well as the clean tank self desrtucted after 10 years of use? I think you got Pine Sol confused with "Red Devil" lye..... Maybe your friend needs to change their diet....!!! Wouldn't think that soap would ruin a waste tank.

I've used Pine Sol for years and never had any trouble with it eating up any poly tank. I would imagine if you dumped the 100% Pine Sol in a empty tank and left it sitting for a long period it may have an adverse effect in the area that it may have pooled in.... I would have to imagine that someone may have dumped a bottle of pin cleaner, then someone else may have poured in another cleaner, maybe some bleach or the RV tank smell good stuff, then some sort of chemical reaction could have occured, causing the poly take to loose it's structural integrity... So if your afraid the Pine Sol will harm your holding tanks, don't use it..... As for me, I'll continue to use the Pine Sol in my holding tank and keep all my tires inflated to the maximum pressures as stated on said tire's sidewall!!!

 P.S.   I'll let you all know when my tank takes a dump and all my tires blow out!! LOL!!

I gotta say I dilutte the no name pine Sol from Wally market.  But as always I appreciate learning new things and maybe I will look in the camping section for a better item.  But...

I like hearing every now and then a shreek from the house

"Where has the dam Pine Sol gone to again!" 

Never used in a dark tank, but it will clean black streaks off the trailers exterior as well as the wax.... Does a good job on an awning also. Don't be afraid to rinse with copious quanities of agua. I would be a bit afraid of the "Simple Green" vapors in a confined space, such as the vapors leaching from a porly vented tank, back into a closed up trailer living area. A glance at the products MSDS sheet may prove me wrong.

After we dump our black/grey tanks,I always pour about 1/2 bottle of Lemon Joy dishwashing liquid in the toilet and dump in the ice cubes that are in the trays remaining,about 3 trays full.I think it helps keep it clean as it goes down the road,it's scouring and sloshing.Never have used Pine Sol,I just use the Campa Chem stuff while sitting still.

RV dealer told me about the Lemon Joy deal.