Fresh Water System Repair for West Covina

Tank, fill, vent and the parts that hold the water

The fresh tank is usually a polyethylene vessel strapped into the floor structure or hung under the coach in the underbelly. It has a fill inlet, a vent so air can leave as water enters, an outlet to the pump, and often a drain. Each of those is a penetration in a plastic tank, and each is a place where a fitting can loosen, a bulkhead seal can harden, or a mounting strap can fatigue and let the tank move.

A full tank is heavy, and a tank that is not properly supported flexes at its mounting points every time the coach moves. Over years that flexing cracks the tank at a molded corner or pulls a fitting boss. Those cracks leak slowly, which means water enters the floor cavity or the underbelly for a long time before anyone notices a shorter than expected supply.

Slow fill is almost always a vent problem. Water cannot enter faster than air can leave, and a vent line that has kinked, sagged into a low loop that traps water, or been blocked by debris will make a tank take several times as long to fill. Owners describe it as the fill being restricted and assume the inlet is at fault.

Water quality issues after storage come from biofilm. A tank that sat with water in it through a warm inland summer grows a film on its inner surface, and that film flavors everything that passes through afterward. Sanitizing the system properly, which means the tank, the lines, the heater and the fixtures rather than just the tank, resolves it. Draining a tank before storage prevents it.

Distribution lines, fittings and the repairs that hold

PEX distribution lines run from the pump through the floor cavity to every fixture, with tees at branch points and shutoffs where the manufacturer chose to fit them. Done at the factory with proper crimp tooling, these joints are reliable for a long time. Done in the field with the wrong tool or the wrong ring, they leak within a season.

Crimp ring joints depend on a correctly sized ring compressed by a tool calibrated for it, and there is a gauge that verifies the crimp. We use the correct tool for the fitting system present in the coach rather than adapting, because a joint inside a floor cavity is not somewhere to accept an approximate result.

Push to connect fittings work through an internal grab ring and an O ring. They are convenient, they are legitimate, and they fail when reused after removal, when installed on tubing that was cut at an angle or scored, or when the tubing was not inserted to full depth. We find all three on coaches that have had owner repairs, and the fitting usually looks perfect from outside.

Support and routing matter as much as the joints. Unsupported PEX rubbing against a metal edge in a floor cavity will eventually wear through. Line run too close to a heat source hardens. Line run without a loop where it crosses a slide mechanism gets pinched. When we open a floor, we correct routing problems in the area we opened rather than closing it back up over the same conditions.

• Crimp joints need the correct tool and a verified ring, not an approximation
• Push to connect fittings fail when reused, scored or under inserted
• Unsupported line chafes against structure until it wears through
• Line near a heat source hardens and cracks at the fitting
• Routing errors get corrected whenever a floor cavity is open

City water inlets, check valves and regulator failures

The city water inlet is a fitting through the sidewall with an internal check valve that stops pressurized supply from back feeding into the fresh tank. When that check valve fails, connecting to city water fills the fresh tank until it overflows through its vent, which owners often notice as water running down the side of the coach for no apparent reason.

The inlet is also a common freeze casualty because it contains a small trapped volume in a rigid housing on the outside wall of the coach, which is the coldest place it could possibly be. A cracked inlet leaks into the sidewall rather than to the outside, which puts water directly into wall structure.

Regulators are the component owners most often trust without verifying. A simple brass inline regulator has no indication of what it is actually delivering, and one that has passed grit or sat unused can stick and pass full line pressure. That is not a theoretical concern, because supply pressure in this region routinely runs well above what an RV system was designed for.

The consequence of unregulated pressure is rarely immediate, which is exactly why it keeps happening. The system holds through a weekend, and a joint in the floor cavity splits weeks or months later. By the time the floor is soft, the connection to the unregulated hookup is not obvious anymore. An adjustable regulator with a gauge lets you see the delivered pressure rather than trusting a fitting to be working.

Freeze damage, winterizing and de winterizing correctly

Coaches in the San Gabriel Valley rarely freeze at home. They freeze on trips, which is why owners who never winterize get caught. One night below freezing at elevation with water in the system is enough, and the split is almost never in a long flexible run. It is in the components that hold trapped water in rigid housings.

Proper winterizing is either a blow out with compressed air at a controlled pressure or a pump through with RV antifreeze, plus draining the water heater, bypassing the water heater so antifreeze does not fill it, opening low point drains, and treating the traps and the toilet. Doing half of it produces a coach that looks winterized and still splits.

Low point drains only work if the coach is level and if the lines actually slope toward them. A coach stored nose high in a row leaves water sitting in a section the manufacturer expected to drain, and that section is where the split happens. This is why blowing lines is more reliable than draining alone on a coach that cannot be leveled in storage.

De winterizing matters too. Antifreeze left in the system tastes terrible and needs a proper flush, the water heater bypass has to be returned to the run position or there will be no hot water, and the system needs a pressure check before the first trip rather than a discovery on the road. We perform winterizing and de winterizing in shop and check the system on both ends of the process.

Repairs in the floor cavity and what access really costs

The honest part of fresh water repair is that the plumbing part is often the smallest line on the estimate. Reaching a line that runs under a fixed dinette, beneath a slide floor or behind a cabinet base is where the hours go, and pretending otherwise helps nobody.

We plan access from the moisture map rather than by opening the most obvious panel. Sometimes the underbelly comes down, which gives broad access on many towables. Sometimes a bay wall or a cabinet floor is a shorter path to the same joint with far less disruption. On coaches where a slide has to be moved or supported to reach the area, that becomes part of the plan and part of the conversation before work begins.

Whatever came apart goes back correctly. Underbelly material gets resealed rather than taped. Insulation that was wet gets replaced rather than reinstalled. Any subfloor that has lost integrity gets addressed as structural work rather than covered, because a floor that is soft under a repair will fail again around it.

This work is done in shop at Yorba Linda, about 22 miles from most West Covina addresses. We do not offer mobile service. Floor cavity access requires lifting equipment, lighting and a level surface, and the repair needs time to be tested and verified dry before the coach goes home. Call (949) 799-3387 to schedule.