Google Googled Hot Water Cylinders And Found The Right Specialist

Founder Larry Page’s luxury yacht Senses is sitting in Auckland needing two new specialized hot water cylinders. So the Google founder’s maintenance company Googles “hot water cylinder specialist” and finds Hot Water Cylinders NZ.

They found the ultimate hot water cylinder specialist right there and then, because his maintenance company went ahead and signed us up for the job. Seeing our expertise and capability, they have trusted HWC NZ to replace the existing units and manufacture the exact same models to get their superyacht ready for sail once again.


The cylinders were designed with the following specifications:

  • 250L horizontal marine style duplex stainless steel hot water cylinder
  • S/S 304 cased & insulated
  • 550dai x 1525 length
  • 3 x custom element flanges to suit existing stock elements
  • 850KPA relief valve and 20mm connection
  • Custom inlet & outlet sizes based on original
  • 20mm cylinder drain
  • No coil
  • 1x tank anode
  • Mounting angle brackets including nuts and bolts


Check out a video of these marine hot water cylinders below:

Marine Hot Water Cylinders

Designed to withstand the special demands of the marine vessels and boats, our marine hot water cylinders are built with the highest quality components to ensure optimal performance and longevity.

Our marine cylinders are made with grade 304 stainless steel, which has good resistance to oxidation even in continuous service in temperatures of up to 925oC. And when you’re out in the water 24/7, corrosion resistance is a crucial factor. In comparison to other materials used in hot water cylinders such as copper-nickel or aluminium-bronze alloys, stainless steel resists salt-water corrosion better which makes it a clear choice for marine hot water cylinders.

That being said, stainless steel is not totally immune to corrosion. It can experience localized corrosion under certain conditions, so some stainless steel cylinders will fare better than others. The difference lies in engineering and design. Needless to say, our team is confident that we can supply cylinders fit for a supercraft like Senses.

The new cylinders had to be the same design because other pre-made units would neither perform well enough for the superyacht’s hot water demands nor sit well with its Philippe Starck interior.

Google trusts its search engine to show the best and most reliable experts in their fields, so much so that they chose Hot Water Cylinders NZ when it showed on the top results.

Gaining the trust of one of Google’s executives says a lot about our team. These people mean business in whatever they do. And we know they only make strategic decisions that will provide the best outcome for them. Senses is a yacht for VIPs, celebrities and the affluent who expect nothing short of luxury, so everything in it must be built to impress.

We don’t take the word “specialists” lightly. We brand ourselves that way because we know our job extremely well. We don’t just sell the priciest cylinders in order to drive sales, we take the time to listen to our clients’ needs and specifications in order to provide the best in terms of performance, efficiency and economy. Whether it’s gas, electric or solar powered, we’ve got the expertise and experience for that!

In the case of Senses, our goal was to build reliable hot water cylinders at par with the standards and specifications of the original. That’s a huge feat, considering we need to design and supply everything from the custom element flanges to the nuts and bolts.

More about Senses

Photo credit:

Photo credit:

The 59.2 metre expedition motor yacht was engineered by Germany’s Fr. Schweers Shipyard in 1999 and was last refitted in 2015. Built to surpass the challenges of the world’s oceans, Senses is Lloyds rated and deemed perfect for the 21st century adventurer. describes Senses as “the opportunity for a truly unique lifestyle in luxury yachting” with its stylish interiors and comprehensive inventory of equipment. True enough, the yacht features an impressive arsenal of toys including six WaveRunners, two jet skis, kitesurfs, surfboards, kayaks, paddle boards, a Jetboard, a Jetlev and a helipad – plus tons of inflatable toys for endless parties!

The yacht offers lavish accommodations for up to 12 guests, with 7 spacious modern cabins and a gymnasium that can also be converted into a cabin.

Hot Water Demand on Boats

With its 15,000 km plus of coast, waterways and lakes, New Zealand is every boatie’s paradise. Boating is like a way of life, a tradition during perfect summer days for families and solo adventurers alike. Living on boats is also a growing trend amongst Kiwis who love boating and want something other than the typical lifestyle.

Whether you’re sailing for the weekend or you’re on an extended cruise with lots of water adventures in between, you can never have enough of hot water on board. A nice warm shower is the ultimate refresher, washing off the salt and sweat at the end of the day. Especially when you’re wintering someplace on a boat, hot water is something you just can’t live without.

Many boats carry a water heater that operates either from engine heat or on electricity. The problem with the former is that the engine has to be running constantly to ensure a steady supply of hot water. That’s very inefficient when you’re just mooring, and causes unnecessary wear on the engine. The fact that the water in the heater can be heated depending on the temperature of the engine’s coolant creates some serious safety risks. Nevertheless, these heaters work well for smaller boats.

For bigger vessels, a custom-fitted hot water cylinder makes a lot more sense, due to its larger capacity and efficiency.

In the case of Senses which has a private beach club complete with a Jacuzzi, sauna and steam room, having hot water on demand is essential. Now with its new high spec hot water cylinders, Senses is once again ready for charter in New Zealand and the South Pacific.

With the right type and size of hot water cylinder, you can enjoy these creature comforts and luxuries in your own boat, too!

Talk to us for a consultation on any of these numbers: 0800 4 CYLINDERS or (NZ FREE) 0800 429 546.


The District Health Board Is Warning People Against Turning Down Their Hot Water Cylinders To Save Money

Legionnaires’ disease, also called Legionellosis, is a severe and potentially fatal type of pneumonia. It is contracted by inhaling water vapour or steam containing the Legionella bacteria, which is very likely to happen when taking a hot shower.

The bacteria love warm, stagnant water. They can grow in water temperatures ranging 20 – 45oC and thrive in the range of 32 – 44oC, which commonly occur in plumbing systems, spa pools, hot water tanks and evaporative condensers of commercial AC systems. However, Legionella bacteria cannot grow at higher temperatures and are killed almost instantaneously at around 70oC.

legionnaires_disease_in_hot_water_cylindersThis is why the District Health Board is sending a warning against turning down hot water cylinders in an attempt to save money. For the same reason, the Building Code also requires hot water systems to have the storage water heater thermostat set to a minimum of 60oC.

This warning should not be taken lightly. Legionnaires’ disease can lead to respiratory failure, septic shock or complications that may result to organ failure or even amputation, which was sadly the case for two people in Hawke’s Bay in 2015.

Facts about Legionellosis

  • The illness is caused by Legionella strains, particularly pneumophila and L. longbeachae, which are ubiquitous in the New Zealand environment. They are found in both potable and non-potable water systems, and can easily find their way into engineered water reticulation systems.
  • Hot water cylinders are a breeding ground for the Legionella bacteria, as are boiler systems, water-cooling towers, garden hose-pipes, air conditioners and even mist sprayers in the grocery store produce section. Legionella can also survive in some soils or composts.
  • Legionella bacteria cannot be contracted by drinking contaminated water nor transmitted from one person to another.
  • In healthy people, the disease manifests as a very bad cold with symptoms including high fever, chills, headaches, muscle aches, loss of appetite, cough and occasionally diarrhoea. But for those with immature or impaired immune systems (i.e. children, older people, smokers, alcoholics, cancer patients, etc.), the effects can be much worse and fatal.
  • A mild form of Legionnaires’ disease, known as Pontiac fever, doesn’t affect the lungs and usually clears within two to five days without treatment.
  • Although the bacteria primarily target the lungs, it can also cause infections in wounds and other parts of the body.
  • Some infected people will suffer long-term health issues such as fatigue, neuromuscular and neurologic symptoms.
  • The legionella bacteria primarily spread through micro water droplets, but it can also be transmitted via aspiration of contaminated water or working with contaminated soil.

Are you safe from Legionellosis?

Homes and workplaces are generally safe. But as a homeowner, it is your duty to undertake regular maintenance of your water systems. Workplaces are also required under legislation to comply with building maintenance guidelines, especially those with cooling towers.

Many infections are without symptoms as healthy adults have antibodies to the bacteria, showing evidence of previous exposure. Only a small number of cases will have had an illness with symptoms.

What can you do to minimize your risk?

Prevention should always be the first course of action.

  1. Since Legionella bacteria cannot survive in water at 60oC or above, you should keep your hot water cylinder at a minimum temperature of 60o
  2. For households with a roof collected tank water supply or other non-reticulated water supply, the water tank must be maintained according to the guidelines.
  3. When working with potting mix, soil or compost, wear a mask to avoid inhaling dust. Dampen the soil to avoid stirring up the dust too much.
  4. Installing tempering/mixing valves are recommended to ensure safe water temperature at the tap. To prevent burns and scalds, water tap temperature should be no more than 45oC for children and no more than 55oC for adults.

For more information about keeping your water systems safe, contact our team at 0800 429 546.


Chlorine Can Damage Your Hot Water Cylinder

The sudden spike in hot water cylinder failure in Christchurch is said to be connected to the recent introduction of chlorine to the local water supply, according to this report. The controversial chemical is believed to have led to leaks in pipes and cylinders. Since the issue broke, more than 2000 hot water cylinders have been replaced.

Property management firms and cylinder manufacturers have reported an increase in plumbing faults and demand for new units.


Chlorination and Corrosion

New Zealand has had many years of chlorine-free water supply until recently when a deadly gastro outbreak due to water contamination happened in Havelock North. Many people argue that chlorine may not be to blame as some parts of the country with chlorinated water did not experience the same problem. So is the Christchurch dilemma an isolated case?

It turns out that Christchurch isn’t the only one. Last year, plumbers in Hastings reported a 30 per cent spike in hot water cylinder breakdown following the chlorination of the local water supply, according to a New Zealand Herald report. The same thing happened to Hastings and Napier as well.

So does chlorinated water actually cause corrosion?

Chlorination may not be directly to blame. However, the presence of chlorine in the water supply is a major contributing factor. Older cylinders may have existing cracks or pin holes, which are usually plugged up by mineral and lime scale that has built up. When chlorine is added to the water, it cleans and dissolves the sediments in the cylinder, exposing the cracks or pinholes. This explains why a hot water cylinder which has been working fine in the last 3 decades is suddenly failing.

That bChlorine_can_damage_your_hot_water_cylinder_2eing said, some cylinders that have only been running for 18 months also failed. Many units in the area were newly replaced in the aftermath of the quake. So many pointed out that chlorine may also strip off the protective oxide coating from the copper, making the cylinder more prone to corrosion and leaks.

Experts analysed a number of defective cylinders in Christchurch and found multiple corrosion pits, which they concluded to be the cause of the unit failure. Traces of chlorine were identified in all pitting sites but were not present on non-pitting surfaces, which proves that chlorinated water actually causes a chemical reaction in the pipes.

Causes of Corrosion

Copper is nearly a noble metal due to its reluctance to oxidation or corrosion. Copper in hot water cylinders also has an added layer of oxide lining that makes it practically “rust proof”.

causes_of_corrosion_hot_water_cylinderHowever, copper may actually corrode when there is galvanic action or electron movement between the copper and its surroundings. Here are several other factors that can contribute to the corrosion of pipes, fittings and fixtures. The degradation of a cylinder depends on the rate at which one or more of these factors work:

  • Chemicals – Water carries naturally occurring and added minerals and impurities which can effect corrosion in various ways. For instance, high levels of calcium (which often present in hard water) may lead to calcification in pipes and fittings. When the water is chlorinated, the chemical compounds in the added chemical can react with copper, steel and plastic pipes which will consequently accelerate the corrosive action of both plastic and metal plumbing fixtures.
  • PH levels – Copper has an oxide lining that could be stripped when the water is at a certain PH level. This leads to a more rapid rate of corrosion.
  • Oxygen – Both water and oxygen are required for rusting to occur.
  • Temperature – Chlorine in extremely hot water is particularly corrosive on copper, brass, galvanized iron and stainless steel pipes and fittings. While this fact is taken into consideration when designing hot water cylinders, corrosion is inevitable and will happen gradually.

causes_of_corrosion_hot_water_cylinder_2Oxidation can happen uniformly or non-uniformly. Uniform surface corrosion is usually caused by low PH or high PH and when the copper comes into contact with phosphates or air. This gives the copper a greenish patina. Non-uniform corrosion drills pits into the surface. If the pitting is severe enough, it can penetrate a pipe and cause pinhole leaks.

Preventive checks

For cylinders to fail in less than 10 years is unacceptable, especially since replacement can cost a bomb and a lot of trouble.  Preventing corrosion can be more challenging when the water is mass treated. But the good news is you can pre-empt future failures and extend the life of your hot water cylinder. Here’s what you can do:

  • Watch out for moisture. It’s easy to overlook a slight drip, but you’ll know it’s there when the carpet is getting a bit wet or moist.
  • Keep an eye out for discoloured water or the appearance of blue-green stains in sinks and baths. If there’s white buildup around the fittings, that’s already a sign of calcification.
  • Have your cylinder checked according to maintenance schedule to find any pitting and stop potential leaks in their track.
  • If you are installing a new unit or a replacement, check with your installer that the cylinder is fit for purpose and has proper galvanic protection. We recommend replacing alloy-coated cylinders with Titanium-coated ones, because Titanium is more resistant to corrosion.
  • Make sure to choose a reliable installer with a good record, as correct installation has a major effect on the performance and life of your cylinder.
  • Make sure the sacrificial anode is in good condition. To find out more about sacrificial anodes click here.

When it happens, corrosion won’t be your sole problem. The water damage caused by leaks can impact your flooring, cabinetry and building structure as well. So it’s imperative that the unit and pipework are checked and maintained as needed.

For more information, contact our team today on 0800 429 546.

Is Your Hot Water Cylinder Pilot Light No Longer Working?

Did your gas water heater suddenly stop working? Chances are the pilot light, which ignites the gas burner on your hot water heater, has gone out. If it has, you can try re-igniting it according to your water heater label. If the pilot light keeps going out, there are a number of potential problems to check.


  1. A bad thermocouple

The thermocouple allows gas to flow to the burner when it senses heat from the pilot. If it detects an unlit pilot, it automatically turns off the gas as a safety precaution. The thermocouple may stop operating if it is dirty, bent or damaged.

Rheem UV6379L 18 Inch Thermocouple Kit Water Heater Replacement

Dirt and grime can be cleaned off using a piece of sandpaper. If the thermocouple is bent far away from the pilot, you can simply bend it back to its original position, making sure it is close enough to the flame. The pilot light should appear blue in colour. If there is no clear sign of dirt accumulation or bending, then the device may simply be broken and needs replacing. This can be checked using a multimeter which tests the voltage coming from the device.

In theory, replacing a bad thermocouple is easy and only takes a few steps:

  1. Turn off the gas valve – do a quarter turn such that the handle is at a right angle to the pipe.
  2. Unscrew the nuts on the gas, thermocouple and pilot lines.
  3. Turn off the shutoff valve
  4. Remove the gas control and pilot light burner assembly
  5. Use a flat blade screwdriver to pry the spring clip on the thermocouple head and pull out the old thermocouple from the bracket.
  6. Install the new thermocouple (this should be the same type, size and length).
  7. Slide the burner assembly back in and reattach all three lines to the control valve.
  8. Relight the pilot, following the instructions carefully
  9. Reset gas control and refit access cover.


It is important to test for gas leaks, especially when replacing a thermocouple. When the gas burner turns on, soak a sponge in a 50-50 water/dish soap solution and wet the screw joints – air bubbles will indicate a leak.

A word of caution: before cleaning or cleaning, make sure to turn off the gas and wait for the thermocouple to cool to the touch. There will be a faint gas smell when you remove the gas lines, but this should dissipate within seconds. If the smell lingers, you should call your gas utility.

Working with gas carries a lot of safety risks, which is why we don’t recommend doing this operation yourself. It’s always best to err on the side of caution. Also, some hot water heaters also have a closed burner chamber that is difficult access, so it’s better to just call in a registered gas fitter.

Another thing is that, in some older models, the thermocouple can’t be replaced due to the unavailability or discontinuation of spare parts. Here at Hot Water Cylinders, we replace thermocouple on any brand, with the exception of Rheem.

  1. Flex tube problems

If the thermocouple checks out, you might want to check for flex tube issues. Sometimes, this tubing gets kinked in places, which disrupts the gas flow and prevents proper pilot operation. Unkinking may resolve the issue. But if it fails, you’ll likely need a new flex tube.

  1. Dirty pilot tube

If the thermocouple isn’t to blame, try checking the pilot tube. There might be dirt and grime buildup that obstructs the flow of gas. Unlike a broken thermocouple, a filthy pilot tube is much simpler to fix.

To start the process, turn off the gas and wait for the pilot to cool. Then, take a needle and clean the tube making sure to take out any blockage. After cleaning, turn the heater on and check if the pilot light will ignite. If it doesn’t repeat the process until everything works fine again.

  1. Main control valve issues

When all other issues are ruled out, the last thing you could check is the main control valve. It is rare for main control valves to go out but it is still possible. If you get a good result after testing the thermocouple using a multimeter, then a bad main control valve might be the culprit.

  1. Gas regulator issues

The gas regulator basically works by opening to let higher-pressure gas into the system and quickly shutting down when the “downstream” pressure reaches the desired level. The moving parts in this device are constantly in use and, hence, are prone to wear and tear. If the gas regulator is worn out, you’ll notice the pilot on your water heater, furnace and other gas appliances snuffing.

Other possibilities include a leak that is causing the burner to extinguish, an ignition that needs replacing or intermittent low gas pressure due to system fluctuations.

It’s a tall list of things to remember for the uninitiated, but a licensed gas fitter will have the expertise to find and fix the issue quickly and safely. They will also keep you from making errors that might make your warranty void.

If you are not able to light the pilot on your water heater, contact us on 0800 429 546 or use our advisor.


The Importance Of Seismic Restraints

Do you want this to happen to your cylinder?


If you don’t, seismic restrains are an excellent choice when installing your cylinder.

What are seismic restraints?
Seismic restraints for hot water cylinders are steel straps used to keep a hot water cylinder in place, preventing it from falling during an earthquake. They are affixed by screwes and washers of a certain standard to the wall framing around the cylinder. Hot water cylinders are heavy items, with a 135 litre cylinder weighing around 170 kg when it’s full of water. If there are no restrains, this is quite a lot of weight to be flung around in an earthquake, not to mention if you have an even bigger one. It can also damage other items such as pipes which are connected to it, and cause a flood.

Along with this, NZBC B1.3.2 standard requires building elements (including storage water heaters) to be adequately supported including support against earthquake forces. The method illustrated in Figure 14 is acceptable for water heaters up to 360 litre capacity. Where fittings and pipework are attached to the water heater through the supporting platform or floor a 50 mm minimum clearance shall be provided between the fitting and the support structure. 6.11.5 An alternative acceptable solution for securing storage water heaters against seismic forces is given in Section 203 of NZS 4603.


If you are getting a new cylinder installed, make sure that it comes with a seismic retraint kit!

Retrofitting a seismic restraint kit
If you already have your cylinder installed and are not looking to replace it anytime soon, it is possible to retrofit seismic restraints to your exisiting cylinder. However, this is more complicated than installing with a new cylinder, since access behind the cylinder is required. If this is something you would like to do, it is best to contact us to discuss the job.


Hot Water Cylinder Experience Is Key

We all want to get the best value for our dollar, so we try to get the best prices from suppliers whenever we can. Having said that, the best price doesn’t always give you the best deal. Lower prices may reflect low-quality goods and services which may not be the most cost effective option in the long run. So while price is important, a better gauge to use when choosing a supplier is experience.

This is especially important when you’re buying big-ticket items like your hot water cylinder. Only an experienced supplier will be able to help you choose the right product that will heat your home efficiently and economically. Here’s why

Hot_water_cylinder_experience_is_keyExperience means better quality

“The more you do, the better you get.”  If you’ve been doing the same thing for years, you tend to get better at it. Hot Water Cylinders NZ has been in the business for years now, and we’ve installed over 1,000 units in the last financial year alone. This makes us the hot water cylinder supplier and installer with the largest experience in New Zealand.

In all our years of operation, we have learned all the tricks of the trade and found the best systems that provide the best value for our clients. We know that what works for one household may not work for another, so we make sure to provide tailored solutions every time.

There is a right hot water heating system for every installation job. We design our systems based on clients’ individual hot water usage and budget. Our goal is to ensure efficiency and economy, regardless of the brand. We are not partial to one brand, because we know all brands have their own good qualities and features that may work for different types of home. We do endorse brands like Rinnai and Bosch, but only because we’ve already proven them to be reliable and effective. Still, we stock all kinds of hot water cylinder systems from different brands to give our clients a comprehensive selection.

Experience means better service

Customer satisfaction is the hallmark of our service. Our referrals and repeat business are the best testimony to the quality of our work, and we work really hard to ensure our clients only have good things to say about us.

Experience taught us that a strong relationship benefits both parties. So we’ve made it our commitment to build and sustain true partnerships with our clients, making every effort to deliver the best service possible.

Experience also means better value

Even with new hot water heating technologies entering the market, we are not quick to upsell our clients to the latest product if it’s not in their best interest. In fact, there is often no need to replace your hot water cylinder, unless it’s already too old or inefficient.

Since a heavy price tag does not equal quality, we don’t push sales on the most expensive system in our range. Nevertheless, our experience taught us that some of the most reliable hot water cylinders will cost a bit more than the average systems. So you might find that spending a bit more on a cylinder today will give you greater savings in the long run. We always advise our clients not to look solely at the price but to weigh out the features and functionalities among their options, in order to make a smarter decision.

Because we know the right strategies for all kinds of installation, we can help you avoid common mistakes that can be costly to repair. For instance, some new installers does not know how to size the cylinder correctly, which results in an inefficient system that costs more to run. With experienced hot water cylinder installers like us, you’ll have your steady supply of hot water running in no time! Our systems are built to last and come with comprehensive warranties for your peace of mind.

Experience means compliance and safety

As experienced installers, we are highly familiar with applicable codes and regulations. We have learned all the things that could possibly go wrong with a hot water cylinder installation, so rest assured we also know the ways to avoid them.

Our installers are certified plumbers and gasfitters with decades of combined experience. And our systems are all tested for safety.

Homeowners also have a role in ensuring the safety of their hot water cylinder. Although the unit will remain hidden in a utility closet or basement, it needs regular maintenance for safety purposes. We make sure to educate our clients about safe operation and upkeep, particularly of certain components such as the pressure relief valve, vents and the temperature control.

Experience means expert advice

If you can’t decide between a vented and unvented cylinder, solar hot water cylinder or gas-powered water heater system, we’ll explain everything you need to know without the complicated jargon. With us, you won’t be left in the dark. If you’re not yet familiar with your options, we will explain how each hot water heating system works, what type of fuel is best for specific hot water usage, how much they cost, and what the benefits and disadvantages are. We also educate our clients about heat-loss figures, reheat times and insulation to give them a better idea of how efficient hot water cylinders should work. We’ll guide you in choosing the most suitable system for your budget and heating needs, and make sure the system is future proof to give you maximum return on your investment.

At the onset of every project, we encourage our clients to voice out all their questions or concerns. We are always ready to give a straightforward answer. In our experience, problems sometimes arise due to non-communication, and these mistakes can blow the client’s budget out of proportion and also reflect badly on our service. To prevent this, we make sure our clients are well informed before they sign a contract with us.

Whether you are buying a new hot water cylinder or replacing your old unit, you may contact us us for unbiased advice or a no-obligation quote through these numbers: 0800 4 CYLINDERS or 0800 429 546.

Milky Tap Water: What Are the Causes and Solutions?

So you turn the tap for a glass of water, and you notice that the liquid coming out of it isn’t clear but milky. But then, after a few minutes, the milky water starts to clear up until the cloudiness is all gone.


What could have caused the milky appearance, you might ask? Well, there are a number of possible reasons for this:

  1. Air bubbles

Milky water, also known as white water or cloudy water can be caused by air bubbles that get trapped in the pipes. When water-soluble gases such as oxygen, chlorine, hydrogen sulphide, carbon dioxide and others enter the mains supply, they create air locks or air pockets in the plumbing system. As these gases are carried along the pipes, they get dissolved in the water. When you open the hot water tap, the pressure is released and the dissolved gases spurt out into millions of tiny air bubbles. This is what gives your hot water the white, milky appearance.

All main supplies contain a small amount of air, but a tear or damage in the pipe may pull in additional air. A change in the water pressure may also be to blame. An increase in pressure causes excessive air to get trapped in the pipeline. This can happen if:

  • Your home’s plumbing system and heater use the well system.
  • There is disturbance in the water distribution pipes, such as when utility companies switch from one well source to another.


Milky water is also common when the weather is cold. As water passes through the pipes in your home, it is mixed with oxygen. When it’s cold outside, more oxygen bubbles get into the water, hence the cloudy water effect.

If the water is left to stand for several minutes, the dissolved gases will start to separate and the cloudy effect will go away. This reaction is very much similar when you pour carbonated drinks into a glass.

  1. Your water heater’s anode

If water from your hot tap is excessively cloudy and generally stays that way, the issue may be with your water heater itself.

The anode rod (factory installed) in your hot water cylinder is there to inhibit rust by maintaining an invisible film of free hydrogen on the entire surface of the heater. The anode is placed where rust initially forms – in the water tank. It acts as “sacrificial metals” which draw the metallic ions in the cathodic area and keep them from going into the solution, protecting the tank against corrosion. This is most common in water heaters that are less than one year old. It disappears over time.

When water from ALL of your hot water taps turns milky, it could be a sign that your anode needs replacement. The good news is replacing an old anode rod is relatively easy and inexpensive.

  1. Sediments

Sediments such as sand, dirt and tiny particles from rocks in the ground can get into your water supply. This can happen when there are drilling activities nearby.

It’s easy to tell whether the milky appearance of your hot water is caused by air bubbles or by tiny particles. Wait for the water to clear up and watch. Air bubbles tend to rise to the water’s surface, while sediments tend to sink into the bottom or do not clear at all.

Like air bubbles, the presence of particles in the water does not make it harmful but aesthetically unpleasant.

  1. Methane Gas

It’s highly uncommon but not impossible. This problem can occur in areas where gas and oil wells are nearby. Methane is a flammable gas, so having it in your water source can pose problems. It is hard to detect since it is odourless unless the water also contains hydrogen sulphide. In addition, methane acts the same way as air bubbles –they also rise to the water surface and escape into the open air.

The usual fix for water containing methane gas is installing an aerated tap, which permits the gas to dissipate faster. The aerator must be vented to the open air to prevent the risk of fire or explosion.

Is the water safe to consume?

You may notice a difference in the smell, taste and overall aesthetic of your water. But as off-putting as milky water may look, it is completely harmless and safe to drink or use.

However, please note that cloudy appearance that is another colour other than white (i.e. brown, yellow or green) can indicate presence of bacteria, metals, minerals or other contaminants. This is often the case when the cloudy water effect does not clear up after some time. Cloudy water of this kind may have adverse health effects when consumed.

What can you do?

If water from all of your home’s taps appears cloudy, the problem could be from a pressurised water system. If only a single tap produces cloudy water, then the issue is with that fixture alone. Cloudy water from a hot tap can be an indication of a problem with your water heater.

Milky water caused by air bubbles or dissolved gasses can be resolved with aerated taps. Sometimes it cannot be fixed entirely, but aerating the water significantly reduces bubbles.

The cloudy water effect should not last longer than 24 hours. If the milky appearance of your hot water bothers you, you can:

  • Keep the taps running until your water runs clear.
  • Check with your neighbours to find out whether they are having the same issue. If such is the case, it is advisable to notify your water supplier of the problem.

If the situation doesn’t clear up itself, it is advisable to call in Hot Water Cylinders NZ to check whether things look normal or you need to take further steps.

We will come and take a look, so we can determine the right reasons and provide appropriate solutions. Contact us on 0800 832 638!


Rinnai Discontinues the iHeat Ducted Heating Range

Rinnai Corporation, the leading makers of tankless gas water heaters in New Zealand, announces the discontinuation of their iHeat central heating products dues to “cost increases of key internal components.”


The Rinnai iHeat is a ducted heating system that uses hot water to warm and circulate air, providing fast central heating to the entire home. The system is designed to operate in conjunction with a Rinnai Infinity continuous flow water heater. It has been touted as a healthy central heating option as it maintains the air quality and reduces the likelihood of allergens entering the home. The iHeat system is defined by its discreet installation and high energy efficiency (up to 80 percent).

Despite its wide public reception and positive reviews, the Rinnai team has decided to stop its production as a result of their ongoing product rationalisation, citing the following reason:

“Cost increases of key internal components has made producing the iHeat uneconomical.”

iHeat products will remain on the market until the end of December this year, or until stocks have run out. Nevertheless, Rinnai reassures iHeat users that spare parts will remain available and all warranties for iHeat will be honoured over the long term.

An Alternative to iHeat

With the iHeat phased out, Rinnai offers an equally efficient and powerful central heating system: Brivis ducted heaters.

Brivis is the leading brand of gas ducted central heating solutions in New Zealand, and has only been recently owned as a subsidiary of the Rinnai Corporation. The brand supplies a complete range of highly efficient ducted gas central heating products specifically designed for the NZ conditions.

“The addition of Brivis to the Rinnai range means that a more complete heating range is now available,” said the Rinnai team. “In most instances where an iHeat has been specified, Rinnai can supply an equivalent Brivis central heating solution.”

Brivis heaters may not have some of the “smarts” found in the iHeat, but their performance is highly comparable. They are also extremely efficient, with the range offering 6-Star rated systems such as the StarPro 6.

Some of the noteworthy features of Brivis ducted heating systems include:

  • Up to 16 fan speed settings that better match air volume and flow to your home
  • Zero ChillTM soft fan that prevents cold drafts on start-up
  • Automatic gas modulator that maintains the temperature level using a minimal amount of energy. You can set your home to a comfortable temperature and leave the system to keep it steadily heated at that level.
  • Ability to create up to four distinct zones
  • Ability to set the system to automatically turn on/off so you come home to a warm house or limit heating when not needed
  • Simple and easy to use programmable controller with both manual and auto modes
  • Compact, splittable and weatherproof units that ensure ease of installation.

More information on the Brivis range can be found at To enquire about an installation, please contact our home heating specialists on 0800 4 CYLINDERS or 0800 429 546.

Rinnai Discontinues INFINITY Composite Recess Box

Rinnai Corporation, leading manufacturer of tankless gas water heaters, announces the discontinuation of its INFINITY™ composite recess box (R1406).

The composite recess box was introduced as an affordable alternative to the metal recess box designed for housing some units from the INFINITY™ range. Composite products are known for being incredibly strong and corrosion resistant, making them perfect for external applications. Despite this, the Rinnai NZ team explains that demand for the composite recess box is low, hence their decision for its discontinuation.

Meanwhile, the metal recess box will continue to be available.

INFINITYTM Metal Recess Box

The Rinnai metal recess box allows you to virtually hide your INFINITYTM unit, pipe work and power supply into a cavity, ensuring a smooth and neat finish to the job.

It allows a continuous flow gas water heater to be partially or fully recessed into an external wall, unlike the composite recess box which can only be semi recessed. The composite recess box is also not suitable for fire rated walls. These are probably why the metal recess box proved to be a more popular option.

Constructed of folded galvanised steel and powder coated white, the metal recess box can easily be painted to match or complement the exterior cladding. It is suitable for the following external Rinnai INFINITY gas water heaters:

rinnai_composite_recess_box_discontinuedR1405 recess box:

  • A-Series: A16-A26 (current range)
  • VT16-VT26 (discontinued)
  • XR16-XR26 (discontinued)
  • V16-V24 (discontinued)

R1407 recess box:

  • EF24 (current model)
  • HD200 (current model)
  • HD250 (current model)
  • XR32 (discontinued)

Installing a metal recess box

The INFINITYTM metal recess box is ideal for new builds or major renovations as it needs to be installed during the framing stage, i.e. before the internal linings, claddings or building wrap are applied.

The Rinnai continuous flow gas water heaters are designed for external installation, and thus your metal recess box must be located in an above ground, open-air situation. The area must have natural ventilation, where flue gases are safely expelled and rapidly dispersed by wind and natural convection.

Generally, it can be mounted on any vertical structure with water and gas connections and enough clearance for the pipe work. You can install it on an outside wall below eaves, balconies and other areas, but you might want to reconsider siting it near bedrooms since water heaters inside a recess box operates at a slightly louder level than units located externally. In most cases, the metal recess box is better located near the kitchen where there is a high demand for instant hot water.

In addition to general clearances, you need to consider your local building codes regarding this type of installation. To make sure your INFINITYTM water heater is compliant and installed properly, consult a licensed gasfitter familiar with the system prior to installation.

For Rinnai installation advice and consultation, you may call us at 0800 TEAM EURO. For more information about the Rinnai metal recess box and gas water heaters, click here.

When Pressure Relief Valves Leak And What To Do

Recently there have been several claims against ‘leaking’ TPR valves. Upon testing it has been found that the relief valve is neither passing nor failing to reseat, the ‘leak’ appears to be water passing out of the blow-out cage which has opened when the easing lever has been operated too quickly during maintenance.


The purpose of the blow-out cage is to act as a ‘back-up’ relief valve which may (in certain circumstances) open when a high flow rate is passing through the TPR valve during emergency relief conditions and is normal.

Incorrectly sized or partially blocked relief drains causing back pressure may also cause the blow-out cage to activate again releasing water at the cylinder. The relief pressure of the blow-out cage is roughly 50% of the pressure rating of the TPR valve.

This new plastic device is manually resettable as opposed to the previous model which had a ‘one shot’ non-resettable metallic mechanism.

To reset the blow-out mechanism please follow the instructions belo

  1. (Fig 1) Once the water flow has ceased to turn the blow-out cage anti-clockwise to remove the device from the TPR valve body.
  2. (Fig 2) Push the valve stem back through the cage until both the stem and the washer are completely removed from the cage (a resonable amount of force will be required to push the bevelled end of the shaft through cage, lubricating oil will prevent the rubber washer from being pinched).
  3. (Fig 3) Fit the washer onto the stem and insert fully into the cage until the bevelled end ‘clicks’ back into position.
  4. (Fig 4) Fit the device into the TPR valve body and SLOWLY re-test the valve.


One thing to note is that sometimes there may be a case where the valve can be genuinely faulty. Depending on age the valve may or may not be under warranty. In such cases, give us a call to book an inspection in.