Basic RVing - Sewer and Fresh Water

I have been RVing in motorhomes since the year Mt Saint Helens blew, 1980.  So that is now 38 years.  I do not claim to be an expert, but I know enough to keep our latest RV working.  You have two parts to every motorhome; 1.  The chassis.  This includes the frame, motor, wheels, and some of the parts that attach to the chassis.  2.  The house.  This is the living part of the motorhome that attaches to the chassis.  Almost all RV's have fresh water and some kind of sewer system.

1.  Sewer system.  Black and Grey

• The grey sewer and tank is what you have from your sinks, showers, and washer (if you have one). So this water is what you have left after washing your dishes, body, face, teeth, or clothing.  
• The black system and tank is human waster either liquid or solid.  
• Most RVs have separate black and grey tanks but not all.  My old GMC had a 29 gallon combined back and grey tank.  I would recommend if you are looking to buy an RV to get the one with separate tanks.  
• You fill up your tanks and then drain them.  If you are hooked to full hookups at an RV park you just wait until your tanks get relatively full and then you drain them.  You drain the black tank first and then the grey tank to flush the black out of the hoses.  Do NOT leave the valves open all the time.  If you do the black tank will build up a pyramid of poo and it will be hard to flush out.  The grey tank flushes out the black.  I recommend you do not completely drain your black tank as the black stuff can get solid at the bottom of the tank.  
• Most RVs have a spray in the black tank to wash it a bit after draining it.  It is best to use that at least every few flushes.  If you are getting a build up drive you RV with a black tank partially full, maybe 25%, and then drain it when you stop at the end of the day.  
• I have used a number of different additives in our black and grey tank.  I personally get one type of the grey tank and one for the black.  My experience is that all of these work.  Some advertise being better for the environment, some are powder, some packets, some liquid.  I generally get liquid and I buy the ones that get the most stars if buying on line.  Some people do not treat their tanks at all.  My experience is that if you are using your tanks a lot they don't need much or any tank treatment.  But if you have had a few days of dry camping and your black tank is 3/4 full you better have some tank treatment to put in it if you have to drive a ways to dump.  I also find that in hot weather putting some treatment down the grey drains in the kitchen and bathroom is a good idea.  Food builds up in the drains and tank treatment usually fixes the odor.  
• I buy disposable rubber gloves for adding diesel and draining the tanks.  They keep the fuel smell off your hands.  And when draining the tanks it keeps your hands clean and gives you extra friction to turn the hoses where they connect.  I don't always throw the gloves away every time.  Used ones that are not soiled are fine to use again.  But if you use them to drain the black tank throw them out.  
• I have used many of the different types of large diameter hoses to drain my tanks.  I find the red  Valtera hoses to work well.  I personally like them better than Camco.  I have had the expensive Lippert sewer hose.  It costs 4 to 5 times what the standard hoses do.  I found the rubber push seal at the end of the hose part that goes into the RV park sewer connector to sometimes not be that solid.  But the hose if very nice.  I made the mistake of opening opening my tank valve when I had the Lippert valve on the end of the hose shut and the hose leaked in several places.  This caused a poo shower to form.  Since then I have stuck with simple hoses.  I tried a bunch and then settled on 10' red ones from Valtera.  I usually carry 3 10' sections with me.  
• I have a clear section where the hose connects to my tank.  That way you can see the color and flow of the drain.  This comes in very handy if you are flushing your black tank with water.  
• We buy toilet paper designed for RVs.  We get it at camping World.  I do not put thicker paper down the toilet.  
• Our high end motorhome had a very unreliable level indicator for fresh water in the tank and black and grey water levels.  You need something reliable.  I put in See Level system a few years back.  It is very accurate.  

2.  Fresh Water 

• I have been using fresh water hoses that look just like the one in the picture above.  The one pictured is from Camco and this is the one I have.  They are white and get dirty.  I have found mechanics hand soap works well to clean them if you get grease on the outside.  You want a drinking water hose like this one if you care about the taste of your water.  Some people only drink bottled water when they are in their RV.  I don't.  I am careful that I run the water for a while before drinking any that has been in the lines for more than a day or two, but we use double filters for our fresh water and it tastes as good as bottled.  
• I have had several high quality hoses from the RV Water Filter Store.  I really like them a lot.  They have solid leadless brass connectors or stainless, and are much thicker than standard hoses.  I am about ready to order two more from them to replace standard light hoses like the one above.  The heavy hoses don't kink easy and last a long time.  The brass ends are much easier to use than the light ones.  But the plastic hand knob is nice on the cheap ones though.  
• You need clean water in your RV.  Our RV has a built in a single standard canister just before the water goes into the coach.  This means the water goes through a charcoal filter to remove chlorine and other chemicals and impurities just before it is used.  This is where the water filter should be.  If you use the charcoal filter before the water goes into the coach then you have a bunch of water that can sit without chlorine for all the time you don't use it.  And this includes your water heater.  We have a second standard canister for sediment after the water pressure meter and before the water softener.  Standard canisters look like this 

• You need some type of pressure regulator if you are gong to connect your outside water directly to your RV.  I recommend you get the best one you can.  And be sure you use it.  I cost myself a number of thousand dollars by being lazy and not hooking up mine once.  The repairs were a royal pain to get done right and water leaked behind one of my walls.  I now have a Watts adjustable pressure regulator.  

• This is the pressure regulator I have.  I also bought this at the RV Water Filter store.  I recommend this regulator and the water filter store.  They are a small business focused on the RV industry and are very fast and reliable.  
• After a few years I got a water softener.  If you travel in parts of the country with hard water a soft water conditioner is a wonderful treat.  Plus your dishes are much easier to clean as is your body when you shower.  You use a tiny fraction of the soap you normally use.  And your RV pipes don't get clogged with deposits.  Mine looks like this.  I got this at the Water Filter Store. Camping World has them too.  

• Turn off the water when you are away from your RV.  And turn off the pump when you are driving.  
• If you filter, and soften RV park water you will end up with an enjoyable product to use.