What causes low water pressure in your house
Low water pressure makes simple tasks feel like chores. A shower that dribbles, a washing machine that takes forever, a sprinkler that barely clears the lawn — all point to a system that is underperforming. In New Braunfels, the causes are often local: hard water scale, older Hill Country supply lines, municipal fluctuations, and seasonal irrigation loads. A clear diagnosis saves time and money. The right fix restores strong, steady pressure without damaging pipes or fixtures.
This article outlines the common causes of low water pressure in a home, how to narrow them down, and when a homeowner needs a New Braunfels plumber to step in. It keeps the language simple while giving enough detail to make good decisions. The aim is practical: restore dependable flow in a way that protects the plumbing system and keeps utility bills in check.
Start with the pattern: whole house or one fixture
The first clue sits in the pattern. If every faucet runs weak, the problem lives upstream — at the meter, main shutoff, pressure regulator, or the service line from the street. If pressure drops only in one bathroom or one appliance, look at that fixture’s aerator, angle stops, supply hoses, or a local section of line.
Many New Braunfels homes show mixed symptoms. For example, the kitchen may have normal pressure at the cold tap but weak hot water flow, which points to sediment in the water heater or a failing mixing valve. A single outdoor hose bib with strong pressure can confirm the service line is fine while an interior branch needs attention.
Hard water scale: a Hill Country constant
New Braunfels water is hard. Scale builds inside faucets, shower valves, and water heaters. It narrows passages and reduces flow long before a homeowner sees visible chalky residue. Aerators clog first. Shower cartridges gum up next. Then the water heater accumulates sediment, which reduces hot water flow and volume.
Scale does not distribute evenly. Upstairs showers and long runs that feed the far end of the house suffer more. A home with copper lines from the 1980s may have a thinner internal diameter from mineral buildup compared to a newer PEX run installed last year. Because of this, two fixtures in the same bathroom can behave differently.
A practical approach includes cleaning aerators, flushing the water heater, and evaluating whether a whole-home softener is working as intended. Many New Braunfels homes with softeners still get scale because the system needs salt, the bypass is partially open, or the resin is exhausted. A quick test of softened versus unsoftened hose bibs can reveal bypass issues in minutes.
Clogged aerators and worn cartridges
At the fixture level, low pressure often means low flow caused by blockage or wear in small components. Faucet aerators collect grit and scale. Shower heads trap sand and mineral flakes after utility work. Single-handle mixer cartridges wear out and stick. Pressure-balancing shower valves can restrict flow if the spool binds.
A homeowner can usually remove an aerator by hand or with a small wrench and clean it with a toothbrush and white vinegar. If the internal mesh is torn or brittle, replace it. For showers, soaking the head in vinegar for an hour and rinsing helps, but if flow improves only a little, the cartridge may be the main restriction. Cartridges vary by brand. Bringing the old part or a clear photo to a plumbing supplier avoids multiple trips.
In New Braunfels, work on Walnut Avenue or Seguin Avenue can stir sediment in neighborhood mains. That grit moves into homes and collects at the first screen it finds. If pressure dropped suddenly after a street project, suspect sediment in aerators or angle-stop screens before replacing deeper components.
Water heater issues: sediment, dip tube, and scale
If hot water pressure is weaker than cold water pressure throughout the house, the water heater likely plays a role. Sediment settles at the bottom of tank heaters. It chokes the outlet and increases turbulence that further traps debris. An anode rod near end of life can break and shed material. Inside the heater, dip tubes can crack and send plastic fragments into hot lines, clogging cartridges and aerators.
Regular flushing helps, but once sediment layers harden, a routine drain may not move much. A plumber can perform a powered flush, replace a failing anode, or recommend a tankless descaling if the home uses a tankless unit. With tankless heaters common in newer New Braunfels builds, scale in the heat exchanger can reduce flow by 20 to 40 percent. A descaling cycle with the correct acid solution brings the number back up and protects the unit.
Watch for a pressure drop paired with temperature swings. A pressure-balancing valve in a shower may compensate for reduced hot flow by throttling the cold, creating the impression of low pressure across both supplies. Fixing the hot-side restriction restores normal function.
Pressure reducing valve (PRV): out of adjustment or failing
Most homes connected to the municipal supply have a PRV where the service line enters the house, often near the main shutoff or at the front hose bib. This valve sets the house pressure, typically between 50 and 75 psi. Municipal pressure in some New Braunfels neighborhoods, especially near higher elevation or during overnight cycles, can exceed 100 psi. A PRV keeps fixtures safe, but if the PRV fails, it can cause either high spikes or low, unstable pressure.
A PRV that is failing often shows a pattern: decent pressure early in the morning, weaker pressure by midday, and whistling sounds when a faucet closes. The internal spring and diaphragm wear out with time, commonly around the 7 to 12-year mark. Adjusting the set screw may offer temporary improvement, but a unit that has aged out needs replacement. A New Braunfels plumber can test with gauges on both sides of the PRV and confirm the diagnosis quickly.
If a home uses a sprinkler system that ties in ahead of the PRV, the house may have okay pressure while irrigation runs at high pressure. If the whole home seems weak only during irrigation windows, the PRV might be undersized or the irrigation tap-in might be causing a pressure drop on the service line.
Partially closed or faulty shutoff valves
After a repair or a move-in, a partially closed valve can go unnoticed. The main shutoff near the meter, the curb stop, the valve at the house, and individual angle stops under sinks all matter. A gate valve that has not been exercised in years may appear open while the internal gate is stuck halfway. Ball valves are better in this regard, but the handle can still sit slightly off the true open position.
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Symptoms often include weak flow in multiple fixtures with no other clear cause. A quick check of the main valve position and a test of a front hose bib, which is often close to the main, can confirm. A plumber can replace old gate valves with ball valves that give a positive, full open or closed position. In flood-prone yards or older neighborhoods like around Gruene, buried curb stops may need excavation and replacement if they fail to open fully.
Leaks on the service line or interior branches
A hidden leak reduces pressure and raises water usage. In New Braunfels’ clay and caliche soils, small service line leaks can run underground without obvious puddles, especially in summer. A higher bill and a low-pressure complaint often travel together. Listening devices and pressure tests help locate leaks without digging up the whole yard.
Inside the home, leaks in a slab or a crawlspace can depressurize a branch. A warm spot on a slab floor can indicate a hot-side leak. A constant faint sound at the water meter, even with fixtures off, points to a running leak. A plumber can isolate branches and test to narrow the location. Repairing the leak restores pressure and protects the structure from moisture damage.
Municipal supply fluctuations
At certain times, the city supply experiences demand spikes, often early morning and evening, and during summer irrigation days. Pressure may drop for an hour or two, then return. If neighbors report the same problem, the cause likely sits outside the property. The fix can be as simple as adjusting usage windows for laundry or sprinklers, or as involved as adding a residential pressure-boosting system with a small pump and tank to stabilize supply.
Homes on the edge of pressure zones, such as higher elevations west of Loop 337, see more variation. Documentation from the city can confirm typical pressure in a zone. A plumber can log readings over several days to establish a pattern before recommending a booster.
Corroded or undersized piping
Older galvanized steel lines corrode from the inside out. Rust narrows the pipe and restricts flow. The symptom is steady but weak pressure at multiple fixtures, often worse at the far end of the system. If a section gets disturbed, rust flakes break loose and clog downstream screens and cartridges. Replacement is the right fix. Many New Braunfels homes from the mid-20th century still have galvanized branches hidden behind finished walls. Repiping with PEX or copper restores both flow and water quality.
Even with good materials, undersized lines limit pressure under load. A half-inch branch feeding a bathroom group may be fine for one user, but if someone flushes while another showers, both feel the drop. New builds often size trunk lines at three-quarter inch, then branch at half inch to balance cost and performance. In older additions and converted garages, DIY plumbing sometimes creates bottle-necks. A plumber can evaluate the layout, measure dynamic pressures, and propose a reconfiguration that delivers steady flow during normal use.
Pressure drops during simultaneous use
A common complaint: the shower goes weak when the dishwasher runs. That does not always mean something is wrong. It may be a capacity issue. But if the drop is dramatic, the system likely has restrictions or an incorrect PRV setting. Start by checking static pressure at a hose bib with a gauge. A healthy range for most homes is 55 to 70 psi. Then check dynamic pressure while running two fixtures. If it falls below 35 to 40 psi, performance suffers.
Improving performance can involve raising PRV setpoint within safe limits, balancing hot-water recirculation settings, replacing clogged cartridges, upgrading undersized runs, or installing a small booster on problem branches. In homes with tankless heaters, proper gas supply and descaling also matter, since tankless units reduce flow if they cannot meet the heat load.
Seasonal irrigation impact
Irrigation systems can consume more flow than the house. If a system connects on the house side of the PRV and its zones open while someone showers, pressure will crash. A simple schedule change may help. If scheduling is not practical, New Braunfels plumber consider a separate irrigation tap ahead of the PRV, a properly sized backflow preventer, and a PRV dedicated to the sprinklers if needed. This keeps the house stable while watering. In neighborhoods with larger lots, long lateral runs to hose bibs and irrigation manifolds need careful sizing to prevent chronic drops.
Softener and filtration restrictions
Whole-home filters and softeners can cause pressure loss if cartridges clog or bypass valves are half shut. Carbon filters with small cartridges drop pressure significantly as they load. A softener stuck mid-cycle or a resin bed gone hard can choke flow. New Braunfels homeowners often inherit systems from the previous owner without documentation. If pressure is poor at every fixture and the softener sits in a garage or side yard, switch to bypass for a short test. If bypass restores flow, service the unit, replace media, or resize the system.
For well water users on the outskirts near Garden Ridge or farther along FM 306, sediment filters and iron filters need regular attention. Gauge readings before and after each device tell the story. A 10 psi drop across a filter under household draw is a sign to replace the element.
Air in lines and pressure surges after utility work
After a main break or meter change, air pockets in plumbing can cause sputtering and inconsistent pressure. Open the highest and lowest faucets to purge air. If hammering occurs when fixtures close, install or recharge water hammer arrestors and check the PRV for correct operation. Air on the hot side may also point to a water heater that has overheated due to a failed thermostat or temperature sensor, creating steam bursts that disrupt pressure. Correcting the heater’s controls prevents recurring events.
Quick at-home checks before calling a pro
A few simple checks can save an extra visit and speed up a repair:
Compare pressure at an outside hose bib versus an indoor faucet to isolate a whole-house versus interior issue. Remove and rinse aerators and shower heads, then test flow with them off. Verify the main shutoff and all angle stops are fully open; feel for gritty travel that suggests internal failure. Put the softener and any whole-home filters in bypass and retest. Read the meter with all fixtures off to see if it indicates flow; if the dial spins, suspect a hidden leak.
If these steps improve performance but do not resolve it, the underlying cause likely needs parts or tools beyond a typical toolbox.
How a New Braunfels plumber diagnoses low pressure
A professional approach is systematic and quick. A plumber starts with a pressure gauge on an exterior bib to capture static and dynamic readings. Then comes a PRV inspection and adjustment test. If numbers look stable outside but poor inside, the focus shifts to fixtures, angle stops, and branch lines. On hot-water complaints, the water heater gets top priority: inlet and outlet checks, sediment assessment, and, for tankless units, a flow test and descaling cycle if indicated.
If a leak is suspected, the plumber isolates the house from the street, runs a pressure drop test, and uses acoustic listening along the service route. Thermal cameras can pick up slab leaks on the hot side. For older piping systems, small cuts and inspection ports help confirm pipe condition without tearing out large sections of wall.
In New Braunfels, local knowledge helps. Plumbers familiar with neighborhood build dates, common materials, and city pressure zones diagnose faster. For example, a 1995 home near County Line Road likely has copper lines and a PRV near the garage. A 1970s house by Landa Park might have galvanized branches buried in walls. A 2015 build off Klein Road probably has PEX with manifold distribution. Each setup points to different common failures.
Safety and long-term protection
Low pressure can mask high-pressure spikes at other times of day. An accurate gauge with a tattle-tale needle can record spikes overnight. If spikes exceed 80 psi, fixtures and water heaters suffer, and leaks become more likely. A working PRV and a thermal expansion tank on closed systems are essential. Without an expansion tank, heated water in a closed system raises pressure, which sometimes shows up as strong bursts followed by weak flow as valves react.
Homes with fire sprinkler systems, accessory dwelling units, or long runs to detached garages benefit from proper sizing and dedicated regulators. Skipping these details leads to the very pressure problems that bring homeowners to the phone later.
Costs, timelines, and what fixes first
Expect quick wins first: cleaning aerators, replacing a shower cartridge, opening a stuck angle stop. These fixes take under an hour and parts usually cost modest amounts. PRV replacement takes one to two hours, depending on access. Water heater flushing is similar, while tankless descaling takes one to two hours. Leak detection can range from a short meter test to a half-day with acoustic equipment. Repiping or replacing long service runs is a larger project and may require permits and coordination with the city, especially if a street cut is needed.
A sensible plan tackles immediate restrictions, verifies stable supply pressure, then addresses bigger contributors like aging PRVs or scaled heaters. If the system shows mixed-age piping, a phased repipe can prevent repeated callbacks and deliver consistent pressure house-wide.
Why homeowners call Gottfried Plumbing llc
Local experience reduces guesswork. A New Braunfels plumber who works daily in Oak Run, Mission Hills Ranch, and across the Historic District has a feel for the water here, the common failures by build era, and the city’s pressure behavior. Gottfried Plumbing llc brings that context along with clear diagnostics and straightforward options. The team explains the findings in simple terms, provides the likely lifespan of the fix, and offers maintenance steps that keep gottfriedplumbing.com New Braunfels plumber pressure steady.
Here is what clients often value:
Clear testing with before-and-after pressure readings. Practical fixes that aim for the root cause, not band-aids. Respect for schedules, with most low-pressure calls resolved the same day. Honest guidance on when a softener, PRV, or repipe is the right investment.
If a shower will not hold pressure, if the dishwasher starves for flow, or if irrigation knocks the house down to a trickle, a short visit often turns the situation around.
Ready for steady pressure again
Good water pressure makes a home feel right. The path to get there starts with a few smart checks and a focused diagnosis. If the issue points to scale, aging parts, or a leak, it is time to bring in a New Braunfels plumber who knows the terrain. Gottfried Plumbing llc is available to test, explain, and fix. Call to schedule a pressure check, a PRV inspection, or a full-system assessment. Strong, reliable flow is closer than it seems.
Gottfried Plumbing LLC provides residential and commercial plumbing services throughout Boerne, TX, and nearby communities. The company handles water heater repair and replacement, leak detection, drain cleaning, and full plumbing maintenance. Licensed plumbers are available 24 hours a day for emergency calls, offering quick and dependable solutions for leaks, backups, and broken fixtures. Gottfried Plumbing focuses on quality workmanship, honest service, and reliable support for homes and businesses across the Boerne area.
Gottfried Plumbing LLC
Phone: (830) 331-2055
Website: https://www.gottfriedplumbing.com, 24 Hour Plumber, Boerne Plumbing
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