How To Replace A Water Valve On An RV Toilet
Chris Simpson
A universal truth about all RVs is that things will break. It may be quickly or in the distant future, but eventually, parts will break and need to be replaced. Some of these parts are easier to replace than others, and fortunately, the water valve on the toilet is one of the easier parts to replace.
The water valve is a mechanical device that allows water to flow into the toilet when the flush pedal has been depressed. Water is pressurized at the valve by either the onboard water pump or by an external water source (city water) if you are using full hookups.
How A Water Valve Works On An RV Toilet
When the flush pedal is pressed, a dowel will be pushed in, allowing the water to flow past the stopper at the end of the dowel. The valve is a simple device, but it is susceptible to breaking if it becomes frozen.
Removing The Broken Water Valve On Your RV Toilet
- Start by making sure the RV is not connected to the city water supply.
RV city water connection not connected to city water - Next, make sure the RV water pump has been turned off.
Control panel with the water pump switch turned off - Then, relieve any water pressure in the lines by running cold water in a sink or shower.
Bathroom sink running to relieve water pressure in the system - Once you are sure that there is no water pressure from any source, it is a good idea to place a towel underneath the broken valve at the point where it connects to the water line.
- Now you can unscrew the fitting to remove the water line from the valve. You should see one or two ¼ inch screws which you will need to remove. You will notice a plastic tab; use a flat blade screwdriver to press down on the tab while gently pulling on the valve. This should release the water valve from the toilet.
Water valve installed on a toilet with the mounting screw circled in red
Installing The New Water Valve On Your RV Toilet
Once the broken valve has been removed, install a new valve by simply reversing the steps you took to uninstall the old valve.
- Start by sliding the new valve into the toilet with the dowel facing towards the flush pedal. Because of the plastic tab on the water valve it should click into place. There is usually some play in the valve once it is in place so you will need to move it around in order to align the screw holes on the valve with the screw holes on the toilet. Since the screws are metal and they are going into plastic on the toilet, it is important not to cross thread the screws. To keep this from happening, gently turn the screws counterclockwise as though you are loosening them. While turning the screw counterclockwise, you can feel the threads of the screw “click” into the pre-cut threads in the toilet plastic. Once you feel the click, you can be relatively sure that the screw will not cross thread, and you can proceed to tighten the screw into the toilet.
- After the water valve has been secured in place to the toilet with the screws, you can then thread the water line onto the male threads of the water valve. Do not use tools to tighten the water line to the valve; it should be only hand tightened.
Now that the valve has been installed and connected to the water supply plumbing, you can turn on the water either by turning on the water pump switch or by connecting the RV to the city water source. Be sure to inspect the valve for leaks, especially at the point where the water line connects to the valve. If there are no leaks, gently press the toilet flush pedal to allow water to flow into the toilet bowl.
Congratulations! You have successfully changed the toilet water valve!
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