Do you keep your RV gray valve open? Closed? How about BOTH?!

Leaving your RV’s gray valve open when fully hooked up allows you to take long showers without worrying about dumping or filling up the gray tank. But what about sewer smells that can come up from the campground sewer system? Here’s how to get the best of both worlds!

One of the luxuries of staying in a full-hook-up campground is the ability to use water freely for showers, cooking and washing dishes. The sewer connection allows you to leave your RV’s gray valve open, so water can run right out instead of filling up your gray tank.

Of course the black valve can NEVER be left open, since “solids” will build up in the black holding tank when the “liquids” run out. But there’s a fair amount of discussion about the gray valve. Some people recommend that you should never leave the gray valve open either, as it can allow odors from the park’s sewer system up into your RV.

Leaving the gray valve closed does mean having to pay attention to the water level in the gray tank, and dumping it every few days. Seems like a shame to have to do that when your RV is connected to a sewer line, especially when you’re staying in a full hook-up site for an extended period of time.

Even though the drains under every sink and shower in an RV are equipped with a p-trap, there is a pipe with a direct connection to the sewer hose…. leading to the tank vents on the roof of the RV. This can allow air from the sewer system to come up through the roof vents. If you’ve ever smelled sewer odors in a full hook-up campground, it’s possible that someone’s RV is venting the park’s sewer system out through their roof.

In a recent RV Travel newsletter, we read about the simplest way imaginable to enjoy the luxury of a full hook-up RV park. You can leave your gray valve in the open position so water runs right down the drain. You don’t have to pay any attention to how full your gray tank is and you don’t have to dump it every few days. But there’s no chance for sewer odors to escape either. It’s the best of both worlds.

Watch the video to see how to do it!

Please use your full hook-up powers responsibly and don’t waste water!



Just a brief follow-up... Although this wasn't a video about tank dumping, it is related, and there were some comments and questions about it. If the gray valve is left open, there isn't any gray water available to flush the sewer hose after dumping the black tank. Here's how we handle that.

Conserving water and monitoring tank levels are just part of life for most RVers, so it's a luxury to be able to forget about it once in a while. When we're in a full hook-up RV park for an extended stay, leaving the gray valve open allows us to take longer showers, while completely ignoring the level in the gray tank. We just use the trick we demonstrated in the video to prevent sewer odors from coming in through the open gray valve.

Then all we need to do is keep an occasional eye on the black tank level. Since we often take the load (sorry) off the black tank by making periodic use of the park's bathrooms (as long as they're clean), it takes a solid (sorry again lol) two weeks or more to fill it up. When it shows 3/4 full, we close the gray valve for a day or two, allowing gray water to accumulate in the tank.

When we're ready to dump, we take a few seconds to put the entire sewer hose back up on the sewer hose support, then dump both tanks, black first of course. Plenty of water has now accumulated in the gray tank, allowing us to flush the sewer hose after dumping the black tank. When we stay in one place for an extended period, we appreciate being able to completely ignore both tanks for two-plus weeks at a time. This way of managing our tanks allows us to do that.

This is a perfectly fine way to handle shorter stays too. After boondocking for extended periods, we'll sometimes treat ourselves to the luxury of full hook-ups for a week or so, leaving the gray valve open and using the same sewer hose technique. We simply close the gray valve a day or two before we'll be leaving the park, and dump both tanks on the morning of our departure.

We don't pretend to be experts on any particular RV topic, and mostly know about maintaining our own rig. But many systems are the same on different RVs. The advice we give works well for us, but be sure to consult a professional technician if you're unsure about working on your own RV.

How To Sanitize an RV Water System

We've been drinking the water from our RV's fresh water tank for over a decade without a problem. It's perfectly safe to do, as long as you sanitize your fresh water system periodically. We do ours about twice a year (keep in mind that we're full-timers... those who store their RV all winter should be fine sanitizing once a year, in the spring).

Clean, safe, sanitary drinking water is a breeze when you take a few basic steps to manage the fresh water system on your motorhome, travel trailer or fifth wheel. Fresh, drinkable, potable H2O doesn't only come from bottled water, but right from your RV's tank, saving money and plastic in the process.

We'll show you how to kill any bacteria that may be present in your camper's water system, and have all the safe drinking water you need.



We don't pretend to be experts on any particular RV topic, and mostly know about maintaining our own rig. But many systems are the same on different RVs. The advice we give works well for us, but be sure to consult a professional technician if you're unsure about working on your own RV.

How To Flush an Atwood RV Water Heater

Rust, lime scale and other debris can build up in an RV's water heater. Left alone, this can shorten its useful life. Simple annual maintenance and care of your RV's hot water system will save you money by extending the life of the heater.

Since we have a Suburban water heater, we're borrowing a friend's RV to demonstrate how to flush an Atwood heater.

Only a few simple items are required, including a wrench to remove the drain plug, a tank flush wand, and some white vinegar (1/2 gallon for every gallon of tank capacity). If you have a Suburban brand water heater, be sure to have a new replacement anode rod on hand as well.

The small amount of time required to do this simple but essential maintenance will pay for itself with years of extra service from your RV's water heater.

Watch our video on flushing a Suburban RV water heater here.
We also have a video follow-up about Suburban anode rods here.



We don't pretend to be experts on any particular RV topic, and mostly know about maintaining our own rig. But many systems are the same on different RVs. The advice we give works well for us, but be sure to consult a professional technician if you're unsure about working on your own RV.

How To Replace RV Water Filters

One downside to moving your house to so many different locations can be the varied and unknown quality of the water available. Many RVs have a rust, scale and sediment filter for all incoming water, plus a charcoal (carbon) filter at the sink and/or ice maker. These all require periodic replacement.

Filtering the main incoming water line for rust and sediment is a good idea, but only a charcoal filter will provide any improvement in the taste. If you have a water dispenser at your sink, or an ice maker, it's quite likely there's a charcoal filter in the supply line.

As charcoal filters also remove chlorine, we avoid using one on the main water inlet, since we want some base level of chlorine in our fresh water tank to help protect the water in the tank (see our video about periodically sanitizing the fresh water tank here).



You can find these filters on Amazon:
5-micron whole-house filter.
Flow-Pur filter #3 (threaded, like ours)
Flow-Pur filter #2 (clip-on type)
(Be SURE to buy the correct one for your RV... threaded, clip-on, etc).

We don't pretend to be experts on any particular RV topic, and mostly know about maintaining our own rig. But many systems are the same on different RVs. The advice we give works well for us, but be sure to consult a professional technician if you're unsure about working on your own RV.