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What causes hot water to smell like rotten eggs?

Several factors can cause your hot water to have a rotten egg smell:

  • Sulfate-reducing bacteria that thrive in your heater tank and produce hydrogen sulfide in your system
  • Magnesium anode rod corrosion in the tank, which sometimes affects cold water as well
  • Issues with the water source such as the home’s water supply or plumbing allowing sulphur compounds to enter

If you’re wondering why your hot water smells, it’s likely due to hydrogen sulfide gas being released into it. This gas is produced either by bacteria inside the tank or from the natural corrosion of a magnesium anode rod. As hot water flows through infected pipes or a contaminated heater, the sulphur compounds transform into smelly gas.

Eliminating the bacteria and the resulting odour can be achieved through tank flushes or by replacing a corroded anode rod with a powered anode system. Complex problems with pipework or well water may require specialists to remove sulfur compounds.

How do sulfur bacteria contribute to rotten egg smell?

Sulfate-reducing bacteria (SRB) release sulfide gas, contributing significantly to the rotten egg odour in hot water. SRB metabolise sulphur to produce sulfide gas, which contributes to the pronounced rotten egg odour in your water.

SRB thrive inside the heater, producing off-putting scents that are hard to ignore. They metabolise sulphur from the water supply, releasing hydrogen sulfide your water system then disperses as a byproduct. This gas then mingles with the water, suffusing your flow with a distinctive sulfide fragrance, particularly when heated.

Without treatment, SRB may lead to corrosion metal components inside the tank until you must get rid rotten compounds from your water to freshen the scent. They are also more common culprits for black residue along tank interiors and seepage into pipes, leading to a decline in the quality of water from your faucets.

By controlling SRB inside your home’s water heater, effective maintenance can mitigate the rotten egg smell your tank emits with flushing methods or shock chlorination. However, sulphur compounds can also enter through the water supply. In these instances, deploying a water softener, filtration system, or consistent maintenance of your anode rod can control SRB and their odorous byproducts.

The role of the anode rod in rotten egg odor

The anode rod inside your hot water tank is essential for preventing corrosion and the associated rotten egg smell. Water heaters are fitted with magnesium or aluminium anode rods that degrade over time despite their sacrificial corrosion protection. However, as the magnesium rod degrades, it can exacerbate the emergence of rotten egg odours.

In areas with hard water, magnesium anode rods typically last between 3 to 5 years. As they corrode, the chemical reaction with water releases hydrogen sulphide gas resulting in that notorious rotten egg smell hot water emits that your guests would notice. Even though the rod is sacrificing itself, the rotten smell indicates it’s time for replacement.

Aluminium anode rods corrode at a slower rate, often lasting more than eight years. But they still produce a rotten egg smell before failing. Replacing the anode rod removes this source of odour while restoring corrosion protection inside the tank.

Should the rotten egg odour persist after replacing the anode rod, bacteria or sulfur in the water supply may be to blame. Our experts can diagnose the underlying problem and recommend solutions such as shock disinfection, filtration systems, or regular anode replacement to address the odour issue long-term.

How to troubleshoot and locate the source of the smell

To identify whether the sulfur smell or rotten egg smell originates from your water heater or plumbing system, Your drains are a critical part of the system, and hence, follow these troubleshooting steps:

  1. Evaluate both your hot and cold water taps - by testing a glass from each, sniffing them to ascertain if the egg smell only persists in one. The scent might smell like primarily a hot water heater smell, suggesting a water heater issue, while a consistent smell in the cold water indicates a plumbing or water supply problem.
  2. Switch off the hot water heater for several hours, then re-evaluate the hot water for any odours. If the odour remains, it suggests an issue with your water system or supply, not the heater.
  3. Inspect pipes and connections for cracks or evidence of sulphur-reducing bacteria, which may contribute sulphides and rotten egg odour.
  4. Consider your well water supply or recent plumbing work, as these factors could introduce compounds that cause your hot water to smell.
  5. confirm the security of your kitchen sink drains as they safeguard your water, ensuring the water is safe to drink and free of unwanted odours.
  6. If the odour’s source evades you, consult with a plumber who can ascertain why your water may have underlying problems via testing. They can advise on water purification methods or heater cleaning to eliminate the unpleasant rotten egg odour.

Step-by-step instructions for flushing the water heater

Follow these steps to flush your hot water heater and remove built-up bacteria contributing to rotten egg smells:

  1. Turn off power to the water heater at the circuit breaker and your gas supply valve if it’s a gas unit. Let the tank cool for a few hours.
  2. Attach a garden hose with teflon tape to the drain valve near the bottom of the tank and route it to an area where drainage won’t cause water damage.
  3. Shut off the cold water supply valve entering the top of the heater.
  4. Ensure the drain valve is open and run a hot water tap to allow air into the tank and facilitate drainage. When you open your hot tap to drain 5-10 gallons, then close the drain valve.
  5. Acquire heater-safe flush chemicals containing chlorine, adept at cleansing both hot and cold water systems, from your local water systems’ hardware store. Read and follow the product instructions.
  6. Disconnect the hot water tap and pour the flush cleaner into the tank’s drain valve. Reclose the valve.
  7. Reopen the water supply valve to refill the tank with the cleaning solution inside. Run hot water taps to circulate it.
  8. After 30 minutes, reopen the drain valve to rid rotten egg residue by flushing the heater thoroughly. Let the tank completely drain.
  9. Close drain valve and reopen cold water supply to refill the tank. Then restore power to the heater when water runs clear.

Flushing your water heater can effectively remove bacteria responsible for rotten egg smells—often the primary source of the odour. For water heater repair, contact a plumber if the odour persists after flushing.

When to replace the anode rod

There are a few key signs indicating when you should replace the anode rod within your water heater:

  • You notice a persistent rotten egg smell even after flushing the water heater.
  • The hot water is slow to heat or doesn’t reach a high temperature.
  • Your system’s anode rod exceeds three years in hard water or eight years in soft water environments.
  • When a mixture of white or grey flakes and sediment comes out of your hot water taps, it’s time for concern.

As the anode rod corrodes over time, it can’t prevent scale buildup or bacteria growth inside the tank as effectively. Replacing the worn rod restores hot water system protection.

For inspections or affordable anode rod replacement services, contact the friendly team at Cecil Hills Plumbing on 1300 349 338 or email jobs@cecilhillsplumbingservices.com.au.

Evaluating if professional help is needed

It’s always wise to seek professional help from a licenced plumber if your hot water smells and you’ve tried troubleshooting rotten egg smells yourself but can’t resolve the issue. Persistent rotten egg odours likely indicate an underlying problem with your hot water system or household plumbing.

Here are some signs it’s time to call in the experts at Cecil Hills Plumbing:

  • The smell lingers after flushing your water heater and changing the anode rod, leaving you questioning, 'does my water smell still persist even after these measures?'
  • The odour happens even with the water heater turned off
  • You have very old pipes that may be corroded
  • There are other plumbing issues like low water pressure or leaky pipes
  • Your home relies on well water, which requires specialised filtration and treatment

Our licensed plumbers can determine the reasons behind certain odours in your water, such as hydrogen sulfide production by sulfur bacteria leading to rotten egg smells. We’ll test your water, pinpoint the origin, and prescribe solutions like shock chlorination, tank replacements, or whole-house water filters to restore clean, odour-free hot water.

For a professional inspection, call Cecil Hills Plumbing on 1300 349 338 or email us to schedule an appointment.

Tips for preventing smelly water long-term

To prevent long-term occurrences of smelly hot water, consider these tips:

  • Flushing your water heater every six months controls bacteria buildup and prevents odours.
  • Have your tap water tested annually and install filtration as needed
  • Replace the anode rod in your heater every 3-5 years for hard water areas
  • For well owners, perform shock chlorination yearly to kill sulphur bacteria
  • Always fix any plumbing leaks promptly to avoid contamination
  • Guarantee all your bathroom fans vent outside to reduce airborne bacteria
  • Consider Whole-house water softeners can remove sulphides
  • Keep drains clear and fill traps regularly to prevent sewer gas entering pipes
  • Ask our technicians about bacteria-resistant tank coatings when you replace your water heater

Proactive preventative maintenance can prevent issues that cause your hot water to smell. Contact Cecil Hills Plumbing on 1300 349 338 for professional assistance safeguarding your household water quality all year round.

When the Smell of Rotten Eggs Signifies a Health Risk

A persistent rotten egg smell in your hot water may signal a significant health risk requiring immediate attention. If shock chlorination and anode rod replacement haven’t resolved the issue, harmful bacteria like Salmonella or E. coli may have infiltrated your water supply.

Contact a licenced plumber right away for emergency water testing if you notice these red flags:

  • Gastrointestinal sickness after drinking hot water
  • Smell coming your taps remains even if you replace the entire hot water system
  • Bad odours emanating from both hot cold taps, not solely hot water
  • Private well owners during flooding or heavy rainfall

Our experts at Cecil Hills Plumbing use advanced diagnostics to check for dangerous pathogens including sulphur-reducing bacteria. We help identify contamination sources and can install disinfection systems and water treatment to restore safety.

Safe water is essential for your family’s health. For emergency testing or assistance with purification solutions, call us 24/7 on 1300 349 338.

Long-term water treatment options

There are several effective water treatment systems that can eliminate water smell like rotten eggs and improve water quality long-term:

Whole-House Filtration

Whole-house water filters remove impurities such as sulphur and bacteria from both hot and cold water before it enters your home’s plumbing. units fitted with a carbon filter are perfectly suited for capturing sulphides responsible for the egg smell your water sometimes has.

Ultraviolet Disinfection

Ultraviolet (UV) systems eliminate rotten egg odours by exposing water to UV light, effectively killing sulphur-reducing bacteria. Preventing bacteria growth helps control rotten egg odours at the source.

Water Softeners

Water softeners remove magnesium and calcium responsible for scale buildup and corroded pipes where bacteria proliferate. Softeners also filter out sulphides. Using potassium chloride salt helps limit bacteria regrowth.

Reverse Osmosis

Reverse osmosis thoroughly filters water by pushing it through a semipermeable membrane, removing dissolved solids and gases like hydrogen sulphide that cause unpleasant smells.

To manage all aspects of water quality including how hydrogen levels affect your water, Cecil Hills Plumbing’s licenced technicians offer thorough solutions with testing, inspections, and continuous support.

Contact our water treatment experts today on 1300 349 338 or email us to discuss the right solutions for cleaner, safer water throughout your home.

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