Why do I not have hot water?
May, June and July are the coldest months on the Gold Coast, and no-one wants to start the day with a cold shower in winter. Unluckily for some clients of Whywait Plumbing who are not Service Partners it is in these months they go to the shower and question why do I not have hot water?
Unfortunately, hot water systems are a case of out of sight out of mind. Continually where hot water systems are concerned, there were warning signs that there was a problem. Over the summer months, hot water problems are overlooked as the demand for higher temperature; hot water is not a critical consideration.
Several warning bulletins in Queensland have been issued by the QBCC and Queensland Health advising homeowners that their hot water systems need to be maintained and serviced frequently.
AS/NZS 3500.4:2018 Heated Water Services
The Australian standard that all hot water installation is based around is AS/NZS 3500.4:2018 Heated water services that are an integral part of the National Construction Code of Australia issued by the Australian Building Codes Board and it is all legal requirements in Queensland.
In AS/NZS 3500.4:2018 there is Appendix M which provides guidelines for the operation and maintenance of your hot water system which is below:
This Appendix provides guidelines for the operation and maintenance of a heated water system.
In order to ensure maximum performance and length of operation, water heaters should be inspected periodically.
M3 MAINTENANCE OF HEATED WATER SERVICES
Heated water services should be maintained in accordance with the following:
(a) Water treatment units: Where installed, water treatment units should be inspected periodically to ensure proper operation.
(b) Water vessels and tanks: All vessels and tanks should be inspected and cleaned periodically, and in accordance with any requirements of the regulatory authority.
NOTE: The frequency of periodic cleaning depends upon the quality of the supply water, design, materials of construction and the pipe system. Combinations of materials giving rise to corrosion should be avoided.
(c) Valves: The following valves should be inspected periodically to ensure proper operation:
(i) Temperature/pressure-relief valves.
(ii) Expansion control valves.
(iii) Thermostatic mixing valves.
(iv) Tempering valves.
(v) Other associated valves/devices.
(d) The requirements of AS/NZS 3666.2, where applicable.
Common reasons for why do I not have hot water
Below are listed the most common reasons we attend to clients jobs who call up to as why do I not have hot water? Listed are elementary troubleshooting ideas that you can undertake yourself to resolve or understand why your hot water is cold:
- blown fuse or circuit breaker – replace the fuse or reset the circuit breaker and if it blows again it’s probable there is a fault with your element or thermostat, and you need to call Whywait out to repair
- Energex relay switch failure – this is not the easiest to detect but if you are on off-peak rates and there are no obvious electrical faults or water leaks then its worth a phone call to your energy supplier to check whether the relay switch has failed to activate in your area
- defective relief valve – most relief valves on the side of the HWS only have a life span of around 3-5 years. Still, they can jam open so first check if you see water running from it by pulling the lever up and then easing back down again. If water continues to run then you need to call Whywait out to service the unit
- no water at all – this is when you wake up turn the tap on and cold water flows, but there is no flow from the hot water. Frequently this a failure of the non-return or isolating valve and a quick way to check is to turn the handle on the valve all the way off and then all the way back on. In many cases, the hot water will simply begin to flow again. However, if there is still no flow you need to call Whywait out for repairs
- water fluctuation from hot to cold – there are several reasons for this occurring, but the most common is a faulty tempering valve. There is nothing you can do to solve fluctuation other than call Whywait and read our information on tempering valves
- water leaking from hot water tank – there is only a maximum of 7 possible points on an HWS tank where there are joints that can possibly leak. Only 2 of those are concealed in the housing so if the water is leaking from the tank and its not from the visible water connections you need to call Whywait for service to check the HWS. In all likelihood, if the hot water tank is more than ten years old then its a 50/50 chance you need a new one installed
The above reasons are the most common problems you will experience with why do I not have hot water. As you can see above, there are only a few simple DIY solutions when you have no hot water.
A word of warning though. Please never open up the housing near the bottom of the tank where the electrical connections are as they are all live wires inside there and therefore very, very dangerous.
Whether you have a solar, heat pump, gas or electric hot water system they do need periodic maintenance so for all hot water problems call Whywait Plumbing now on (07) 5580 4311 as we guarantee a same-day rapid response for hot water problems.
Every week we have clients asking why we are required to install a TMV or tempering valve to their hot water system. The short, simple answer is because it’s the law.
The longer answer is because it’s about safety. A TMV or tempering valve reduces the risk of scalding. This is because storage type gas, electric, solar and heat pump systems are storing hot water at between 60° C and 75° C. You need to be aware a severe hot water burn can occur in one second when the water is delivered at 60° C or higher. Hot water burns like fire because:
- At 60°C, a severe burn can happen in 1 second
- At 55°C, a severe burn would take 10 seconds
- At 50°C, a severe burn would happen after 5 minutes
What is a TMV?
TMV or thermostatic mixing valve installed by Whywait Plumbing
A TMV is a thermostatic mixing valve but is commonly referred to as a TMV. The role of a TMV is to mix hot and cold water together to provide you with hot water delivery at your tap that is at a consistent temperature.
When we install your TMV, we set the temperature to deliver the hot water in all bathrooms at 45°C in aged care or childcare facilities or 50°C in all other bathrooms.
A TMV is compulsory for use when used in common areas for aged care or childcare. A TMV is very accurate and very responsive to fluctuations in incoming water temperatures keeping the temperature to within 1° C of the temperature that it has been set at when we install it.
Accuracy of temperature in the TMV is delivered by a thermally sensitive element which expands and contracts in response to the temperature fluctuations of the incoming cold and hot water. This expansion and contraction regulate the temperature by controlling how much cold water mixes with the hot water. An added safety feature of a TMV is that if cold water flows become too low, they shut down to prevent 60°C plus water being delivered.
What is a Tempering Valve?
Non-compliant tempering valve installation connected with flexihoses replaced by Whywait Plumbing
A tempering valve’s role is also to mix hot and cold water together to provide you with hot water delivery at your tap that is at a consistent temperature.
The tempering valve is a simple three-way valve that is temperature actuated to mix the hot and cold water. These days most come preset at 50°C and when we install them, we test them by measuring the temperature of the water from your hot taps in the bathroom.
A tempering valve is commonly used in residential homes as a one-off valve at the hot water service. A tempering valve is slower to respond to temperature fluctuations compared to a TMV plus it will deliver water to within 3°C of the temperature that it has been set at when we install it.
Which Valve do you Require?
The Plumbing Code of Australia in AS/NZS 3500.4:2018 is very specific about water temperature is section 1.11, which states:
- To avoid the likelihood of legionella bacteria growth, an installation shall store water at a temperature of not less than 60°C
- All new heated water installations shall deliver heated water not exceeding 45°C for the aged, the sick, children or people with disabilities in healthcare, aged care, early childhood, schools and nursing homes. For all other situations, heated water shall be delivered not exceeding 50°C.
Ultimately when we are installing a temperature control device, we are legally obliged to comply with the requirements above and much more as they are prescribed in AS/NZS 3500.4:2018.
Overall a TMV is more expensive to install initially compared to a tempering valve. However, a TMV has a much longer working life span compared to a tempering valve as they are more accessible to service and replace the working parts. A tempering valve, by comparison, is usually just replaced when it stops working as they are not easy to service or replace parts in.
In Queensland, all work undertaken on a TMV or tempering valve is reportable to the QBCC and must have a compliant Form 4 submitted. For your protection always demand a copy of your Form 4.
Replacing Your Hot Water Service – How Will You Know What’s Right For You?
When replacing your hot water service the most common question asked is what will it cost?
Whilst price is always an important consideration, at Whywait Plumbing believe that there are other equally important factors. This article will help you make an informed decision.
Should The Price of the Replacement Hot Water Service Be The First Consideration?
Besides renovating your home, replacing your hot water service is a major cost. It is often an expense that occurs with very little warning.
Unfortunately, unless you like cold showers, this gives you little time to carefully review available replacement options.
Hot water systems are not all created equal and the choice you make today will be one that lasts for the next ten to fifteen years. With ever-increasing energy costs impacting household budgets, having an efficient and well maintained hot water service has never been more important. A cheap hot water service may cost you a great deal more in ongoing expenses.
With So Many Hot Water Systems On the Market How Do You Know Which One To Choose?
With modern technological advances and the push for energy-efficient heating solutions, it’s no longer a matter of just replacing your hot water system with like for like. So how do you know which hot water service to buy?
Hot water services are available in electric, gas, solar and heat pump models, and all come in a huge range of sizes. Purchasing the right hot water service for your needs is something you should seek advice about from a qualified hot water specialist. With a little help from Whywait’s Hot Water Specialists you will be able to select the system that best suits your situation.
Hot Water Service FAQ’s
Before making any decisions about a hot water service replacement you will need to think about:
- What size is your current hot water service and have you ever run out of hot water with your current hot water system?
- Does your current hot water service operate on an off-peak electricity tariff?
- Are your hot water needs likely to increase, decrease or stay the same over the next five years?
- Do you intend to remain in your current property for at least the next five years?
- What is more important to you the initial up-front installation cost or the ongoing running costs?
- Is the quality of the product and length of warranty a consideration when comparing hot water services?
Once you have answered the above points it will be time to consider the available options.