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Why Your Hot Water Runs Out Quickly

Running out of hot water unexpectedly is both surprising and inconvenient. Several factors can cause hot water to deplete more quickly than expected:

  • A water heater that’s too small for your household needs can result in hot water depleting too quickly.
  • Sediment build-up over time reduces capacity
  • Faulty components, Broken dip tubes or damaged heating elements are among the most common causes of significant hot water loss.
  • Simultaneous use of showers and taps can lead to excess demand, rapidly depleting your hot water supply.

As leading Marrickville plumbers since 2013, we understand the question on everyone’s mind: 'Why does my hot water run out hot water?' This article will delve into why you’re losing hot water faster than anticipated, and provide troubleshooting tips to help you get the situation back under control.

Your Hot Water Usage vs System Capacity

The amount of hot water your system can produce is tied to its storage capacity; thus, consecutive showers can deplete the hot water, leading to a cold layer at the storage tank’s bottom and a subsequent shortage.

For instance, a typical 190-litre hot water tank should suffice for two brief showers before requiring a reheating period.

To determine if your water heater is undersized for your household, consider the following:

  • Number of bathrooms/sinks at risk of experiencing out hot water quickly
  • Number of occupants, their routines and overlaps in usage
  • Average duration of showers/baths
  • Capacity of your existing system

Based on these factors, particularly for those with electric water heating systems, too much demand may become clear if an upgrade is required for your home’s demands. At Marrickville Plumbing, our specialists can advise what size and fuel type of tankless water systems best suit your household’s requirements.

Combating Sediment Buildup

Over months and years of operation, sediment buildup inside the water heater tank can be a major cause of hot water running out prematurely. Mineral deposits from hard water and corrosion particles accumulate at the tank’s base as heated water moves through it.

This layer of sediment undermines both the efficiency and the amount of hot water the heater can deliver in two crucial ways:

  • The sediment displaces the water volume inside the tank, reducing the available hot water.
  • It insulates the lower heating element, making it take a long time to heat up the water.

To reduce sediment buildup and increase your water heater’s lifespan, follow these steps:

  1. Annually attach a hose to the drain valve and rinse out the sediment after turning off the water heater.
  2. Set your thermostat between 50°C and 60°C, as higher temperatures can compromise heating efficiency.
  3. Inspect for a broken dip tube needing replacement; compromised dip tubes can mix the hot and cold layers in the tank.

Regularly maintaining your hot water system minimises heat loss from sediment, ensuring quicker water reheating for uninterrupted showers.

Faulty Components - Thermostats & Heating Elements

Malfunctioning thermostats and heating elements often wear out over time, leading to your water heater running out of hot water too soon. Replacing these components is an affordable fix compared to installing a whole new system.

Inconsistent water temperature regulation or a complete failure to heat could be due to a faulty thermostat or pilot light. You might find that while the tank’s top feels hot, the water from faucets runs cold. Testing with a multimeter can help diagnose it before replacing the thermostat.

Heating elements at the bottom of the tank wearing out, resulting in running out hot water is another issue, slowing the reheat rate after water usage. You can check out the DIY basic voltage testing, however, a professional assessment is required to ascertain whether a rebuild kit or a complete element replacement is necessary.

For professional water heater repair and diagnosis of thermostats, heating elements or other underlying issues, trust the expertise of Marrickville’s leading plumbers. We offer prompt call-outs to get your hot water flowing reliably again.

Broken or Damaged Parts

Broken components like a tpr valve in your hot water system can significantly contribute to the issue where it runs out hot water rapidly. Some telltale signs you’re about to use up your hot water include:

  • Visible leaks originating from valves, fittings, pipes, or the tank itself
  • Inconsistent water temperatures - fluctuating between hot and cold
  • Reduced water pressure from the hot water tap and other faucets
  • Loud rumbling or banging sounds caused by sediment accumulation

Problems such as cracked storage tanks, malfunctioning pressure relief valves, faulty heating elements, or burst pipes demand immediate repair by a qualified plumber to restore your hot water supply. Otherwise, left unchecked, these problems can worsen over time and lead to complete system failure.

As leading Marrickville plumbers, we have the expertise to accurately diagnose faults and get your hot water flowing reliably again after thorough repairs or replacements.

Depend on us for all hot water system issues, from sediment flush-outs to heating element replacements, and even full tank replacements—our technicians perform to manufacturer standards.

Preventative Maintenance

Regular maintenance like tank flushing is essential for years of reliable operation, especially if you have concerns about water quality. We advise an annual inspection and servicing by a qualified Marrickville plumber.

This professional maintenance, especially important for an electric water heater, would include:

  • Flushing out sediment to restore heating efficiency and capacity
  • Testing and adjusting thermostat calibration
  • Assessing heating elements and anode rod for corrosion damage
  • Checking for leaks in valves or pipe connections
  • Clearing out debris that may block incoming cold water inlet screens

Investing in preventative servicing lengthens the operating life of your hot water system, prevents unexpected breakdowns, and can even provide small energy savings over time. Contact our team at Marrickville Plumbing today on 1300 349 338 to arrange your next annual tune-up.

When a Replacement is Needed

When certain symptoms suggest that your hot water system is no longer effective, it may be time to consider a full replacement. As your trusted Marrickville plumbers since 2013, we can advise if your hot water heater shows any of these telling signs that it may be time to upgrade:

  • If your household has expanded or your usage has increased, the system may fail to provide adequate hot water, particularly if it’s over 10 years old and approaching the end of its lifespan.
  • If you frequently experience a hot shower turning cold when using several taps at once
  • Loud rumbling or banging noises from the unit while heating water
  • You have visible leaks or rust around the tank exterior
  • Water pressure and flow rate are chronically low
  • Monthly energy bills for water heating seem excessively high

Consider that while components such as thermostats or heating elements can be replaced, a corroding inner tank or exterior leaks make it uneconomical to perpetually repair the system.

Our experienced technicians can inspect your existing water heaters on-site during a standard service call and determine if replacement is required, especially if your hot water is running out fast, or if supplementary repairs and maintenance can extend its functional lifespan a bit longer.

When the time comes for a new hot water heater, trust Marrickville Plumbing to handle full supply and installation promptly.

We provide a broad selection of gas and solar water heaters from top brands, tailored to meet your household needs.Contact us at 1300 349 338 to find the right system or arrange an installation at your convenience.

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