About Manual Valves: Manual valves have been the standard for many years in the RV industry. Installation of this type of valve including the cable pull style needs to be done in a manner consistent with good plumbing practices. The design of the manual valve, when installed incorrectly will shorten the valves useful life.
The valve seals provided with the valve are not interchangeable, other than with valves manufactured by the same company. A seal from one company will not work with a seal from another company. In addition, valve model changes may affect the seal performance making the valve harder to pull, push or not seal properly.
The manual valve should be oriented so the pull is horizontal or slightly up and should be directly in front of the user, so he/she can pull the handle straight out. Side pull, exerts force on the side of the valve and causes premature wear. Placing the pull position in any other than a straight out position, can cause the users hand to slip off, resulting in injury to the customer. In no case should the pull be in a downward direction. The reason for this is simple, when the valve is opened liquid begins to flow. As it does, there exists a “back pressure” for a period of time, and water (waste and urine) will fill the gate area, with the gate body in the down position. Having the valve in a slight up position will allow any liquid that gets into the gate area to drain as the “back pressure” subsides.
Good plumbing practice requires the valve to be placed as close as possible to the outlet of the holding tank. The further from the tank the valve is, the more chance there is that the waste in the black water piping gets compacted and forms a cork. When this condition exists, the valve opens and nothing happens. Clearing the blockage is less than pleasant. The first method is to add water to the holding tank through the toilet, however, be aware that the tank may fill to the point where the water begins to overfill the toilet. The next method is to take a stick or a broom handle, something that is stiff but not sharp and open the toilet valve. Be sure to shut off the fresh water source to the toilet before beginning, as well as, making sure the sewer hose is connected to the coach and sewer inlet. Also open the termination valve. Using the stick as a probe, gently push the stick into the tank, while trying to locate the outlet, being careful not to jab or twist which could damage the tank, the toilet or the termination valve. Once the outlet is located, continue to push the probe until the blockage is cleared and the flow of liquid begins. A very unpleasant experience clearing this blockage; however it is an opportunity to educate the customer on proper dumping and flushing procedures.
If you have any questions or comments please contact us.
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