Most RVs have Cheater Valves, or more formally known as InLine Vents. The purpose of these vents is to assist drainage of the sinks.

Unfortunately, they can be a source of problems. If your RV's sinks are draining slowly, or if you are getting sewer gas smell in your RV and cannot locate the source of the problem, you may have a problem with your Cheater Valves.

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