TLDR
- Cycling pump = small leak somewhere - find the drip first
- Low pressure usually traces to inlet screen or pump diaphragm
- Black tank odors are sanitization, vent, or water-level issues
- Florida heat amplifies any plumbing weakness
- Call 772-276-6465 for on-site diagnosis
RV plumbing is simple in concept - a pump, a network of PEX tubing, and three tanks - but troubleshooting can be frustrating because problems hide behind walls, under cabinets, and inside slide-outs. This guide walks through the most common plumbing issues we see across Port St. Lucie and how to narrow them down before you call us. The good news: most RV plumbing repairs are cheap and fast once the problem is identified.
The Cycling Pump Mystery
If your water pump kicks on every 30 to 60 seconds even with all faucets closed, you have a leak - period. The pump is repressurizing a system that's losing pressure somewhere. Start at the toilet (most common), check under the bathroom sink, then the kitchen, then the water heater PRV, then the outside shower if you have one.
We pressure-test the system on every leak detection call - 60 PSI for 10 minutes catches every leak, even the slow ones inside walls. Read the leak detection service page for what's involved.
Low Water Pressure Diagnosis
Three things cause low pressure: blocked inlet, bad pump, or undersized regulator. The inlet screen on your city water connection clogs with sediment - pull it and rinse it once a year. The pump diaphragm wears over time and stops developing rated pressure - usually 4 to 5 years of regular use.
If you use a pressure regulator (and you should in PSL where campground pressure can spike to 80+ PSI), make sure it's rated 45 to 55 PSI. Cheap regulators rated under 40 PSI won't keep up with showerhead flow.
Black Tank Odor Solutions
Three causes: undersanitized tank, clogged roof vent, or insufficient water level. The fix is methodical: sanitize the system (chlorine flush per EPA guidelines - we do this on every plumbing call), inspect the roof vent for blockage (palmetto bugs nest there in PSL summers), and add 2 gallons of water to the tank after every dump.
Switch from chemical drop-ins to enzyme treatments (Happy Camper, Unique, Walex Bio-Pak). The chemical kind kills the good bacteria that break down waste.
Water Heater Issues
Sediment buildup is the #1 RV water heater issue in Port St. Lucie - our hard water deposits calcium and magnesium on the tank bottom, reducing capacity and corroding the anode rod faster. Annual flush and anode replacement extends tank life by years.
If you're seeing rust flakes or rotten egg smell, see our water heater replacement guide for the full diagnostic.
Tank Sensor Issues
Stuck tank gauges (always reading full, even right after dump) are the most-reported plumbing complaint, and almost always cosmetic. Toilet paper and biofilm coat the sensors and read as full. Fix: ice cube cleaning method (drive the rig with a half-tank of water and a bag of ice in the black tank), or chemical sensor cleaners. We service stuck sensors on every tank service call. Book a plumbing visit at 772-276-6465 - we cover all of St. Lucie County.