Water valve replacement for toilet

Well I guess after three years and putting over 11,000 miles on the T@B with no significant problems, one can begin to expect a little wear and tear on the outfit and the resulting maintenance. First it was the frame cracks as has been heavily noted by quite a few on the forum here. Now it is the plumbing! 

I take some responsibility for this problem that I see has been a common one with many users of the Thetford Aqua-Magic V toilet that is installed in our T@B's.  For the first two seasons I dutifully winterized the whole system with antifreeze and then went through the tedious and irritating process of flushing it all out in the spring.  

Last fall, after having moved to Alaska from Minnesota and having all the "settling chores" such a move entails, I opted for the "easy" method of just blowing out the lines and putting antifreeze only in the traps and grey/black water tanks. So when I first hooked up the water to the city water I was met with gushing water out the back of the toilet! Fortunately for we T@B'ers our toilet is mounted in a shower basin and the water just ran down into the grey water tank until I could rush outside and turn the city water off.  As you will see from one of the YouTube videos I posted below, many RV's don't mount their Aqua-Magic toilets in a watertight shower booth!

https://www.youtube.com/watch?v=yrB2-WBWi88

https://www.youtube.com/watch?v=qbWkCzIoOKc

The problem was and is a common one with the Thetford.  If you don't blow out the whole system with high-pressure air thoroughly, especially through the valve assembly on the back of the toilet, water remains in the bottom of the valve where, when frozen, cracks a weak spot on the valve connector to the hose. The following pictures of the valve assembly and the close up of the cracked hose connector show the fracture of my bad unit. (The jagged white  area) This is where virtually all the bad valves fail according to the RV guy where I bought the replacement valve.  Most good RV parts shops carry these Thetford parts.

Replacing the valve required taking out the toilet. The two YouTube videos show how this is done. The first one shows the best detail of the process, but was one installed in an RV with more working room (but not water sealed as mentioned before).  The second was in a cramped shower toilet similar to the T@B. I had no problem taking the toilet out and putting it back, but I found some difficulty getting the new valve in the slot provided in the toilet. All in all it is not to bad a job compared to pulling and repairing a house toilet, which I have done many times. 

I really don't like the idea of not having a shut-off valve on water lines directly in the area where they service. Having to shut the whole RV (or house for that matter) water supply in case something breaks is always a problem. So the one modification I made while the toilet was out was to install a standard toilet water supply shut-off valve on the 1/2 inch plastic fitting coming out of the wall as shown below.

I then used a hose with a 1/2 inch connection at the toilet end (that I installed while the toilet was out) and a 3/8 inch connection to the shut-off valve. It was very hard to tighten the connection to the valve due to lack of room for a wrench after re-installing the toilet, but using some small, stubby angled pliers I was able to get it tight. I always use Teflon tape on these type of joints even though not required. It assures a watertight connection and makes it easier to take off later for service if needed.  

The toilet is now back in service and I feel better having a shut-off valve right next to the unit! 

Fergie