WHICH WATER HEATER TO USE PRO’S AND CON’S

 

We all know that nothing lasts forever, there will be a time when your water heater gives up the ghost.

Think about it now before it breaks down which water heater you want to go for next. If you want to stick to the same type of heater as you've got now that question is easily answered. However it would need to be a 5 star unit as from the first of July this year if it's a gas appliance. If yours is electric, if you've lived in your house prior to the 1 of July 2008, you can still change it  'like for like' however that's all going to change in July 2009.  If you have an electric storage cylinder and it breaks down after the 1^st of July 2009 you'll have to change it for a solar electric system or a system what is called a heat pump.  Both systems are well in the excess of $ 3000 installed including all the rebates.

5 STAR rating

GAS APPLIANCES

GAS STORAGE HOT WATER CYLINDERS

The 5 star storage hot water heaters have been on the market for quite some time but weren't compulsory.

How they work

Instead of the heat going through the flue pipe and coming out of the top of the water heater, this heat is now also directed on the outside of the cylinder and comes out halfway down at the front.

In effect the heat has been used twice now on the inside and the outside and therefore we have gained higher efficiency of the unit, and we're using less gas. It does bring with, that the flue gases are cooler than from the old system and will be more visible. (steam coming out of the unit)

DISADVANTAGE

People who have got  90 liter or 80 liter hot water services need to be aware that for a replacement they have to go to a unit of 130 or 135 liter. The smaller capacity cylinders are not manufactured   with 5 star technology. However manufacturers say that the efficiency of the bigger unit is better than the existing smaller units. It's still is the ugly looking cylinder often in the wrong place e.g undercover are, patio.

ADVANTAGE

If it's like for like there's no problem and you will keep on getting your hot water like you used to. Once you open the tap water will come through instantly, compared to an instantaneous unit which wastes a little bit of water in the starting up process.

INSTANTANEOUS WATER HEATERS

Highflow models

Despite the small size, the Highflow range provides higher capacities than ever before with flow rates including 17, 21 and the even higher 26 litres per minute.  State-of-the-art technology monitors heater function at all times, from fan speed to water pressure, from incoming temperature to gas modulation, from diagnostic functions to precise outlet temperatures.

Able to deliver temperatures accurate to single degrees, the Highflow range allows the user to select the temperature by using up to 4 optional temperature control pads.

Digitally controlled, the outlet water temperature remains set at all times, to ensure that families can bathe safely.

The electronically controlled range of water heaters is at its most effective when coupled with temperature controllers. Each appliance is capable of handling up to 4 controllers.  This allows precise control of water temperature throughout the kitchen, bathroom, laundry and en suite.

Accessories available include the recess box (fully enclosed and lockable) and pipe cover.

DISADAVANTAGE

The only snag is these higher output units most likely need the gas supply pipe size increased.       Just imagine that in order to heat 17 liters, or more, of water per minute we need a fair bit of gas to achieve that. It would need the installation of a power point near the unit since it is electronically controlled.

ADVANTAGE

Gas consumption can be significantly reduced when using a control pad. If installed in a recess box it is hardly visible. On the high flow models you'll also find that if somebody else is drawing hot water in the kitchen whilst your having your shower, the pressure drop is minimal.

Hydropower - The new generation of hot water systems
Forget about installing a power point next to your new hot water system, replacing batteries that have died or trying to light an extinguished pilot light. How can you light a flame with water?             You can! The new generation of instantaneous hot water systems uses Hydropower technology.
The Hydropower system uses the power of water to ignite the pilot light. As soon as the water tap is opened, the water flowing through the tank drives a turbine in the hydrodynamic generator, which creates the electrical energy required to ignite the pilot. This means that only gas and water connections are required and batteries or power supply are no longer needed.

Key advantages:

• Energy savings - Unlike conventional systems, a constant burning ignition flame is no longer required in stand-by mode.
• Low emissions - Machines with Hydropower technology consume up to 25 percent less gas than conventional gas hot water systems that use an ignition flame.
• Economy - Less energy consumption means lower running costs.

DISADVANTAGE
It takes a few more litres of water before the hot water comes through because there is a starting up process involved with the instantaneous systems.

However if you changed from a hot water storage cylinder (mains pressure hot water) to one of the instantaneous units at 16 liters per minute you will find that the water flow has dramatically dropped and its very well possible that you're not satisfied then what you where used to.                                     If you wanted to change from a hot water storage cylinder to an instantaneous unit we would always recommend an instantaneous unit that can give you at least 21 liters of hot water per minute.

It needs to be investigated to see if the gas pipe installation you've currently got can carry sufficient gas for this unit, the gas pressure coming from the gas meter.

I any case when you're ready we'll come over and can check this out for you.

SOLAR GAS BOOSTED

Solar gas boosted is a split system where the panels are mounted on the roof and a cylinder at ground level.  The cylinder has got a booster unit fitted at the front which is the same as an instantaneous water heater. The system does require a pump that circulates the water from the hot water storage cylinder to the panels on the roof.  When a sensor measures the temperature and it's not hot enough it will divert the water through the instantaneous unit and heat it as to requirement.

ADVANTAGE

As with any solar unit you can benefit from free hot water throughout the summer. It can be positioned on a part of the roof where it will minimize the long draw off when you open a hot water tap.

DISADAVANTAGE

There are many moving parts in this system which are liable to break downs and surely the installation and purchase cost are a lot higher than other systems.

ELECTRIC STORAGE HEATERS

These units will be phased out as from next year July completely. It has to be changed over to a heat pump or a solar electric unit. Both systems are not cheap to install.

THE HEAT PUMP

The basic principle of a heat pump water heater is similar to a refrigerator working in reverse. When hot water is drawn off and cold water enters the tank, the thermostat activates a fan, a compressor and a circulator.  The fan draws outside air in through the air inlet louvers at the top of the water heater and the pump circulates water from the bottom of the storage tank and through a heat exchanger. Heat is absorbed from the air by an evaporator and transferred into the water through the heat exchanger.

Sounds all rather technical and complicated and it needs to be mentioned what cost would be involved when the unit breaks down.

SOLAR ELECTRIC

In our view Solar electric would be the best way to go. No moving parts apart from the element that will only be used in the winter time. By having the panels and hot water cylinders close coupled on the roof there's no need for a pump to run and circulate the water, this is all a natural process. Water heated in the panels will rise, like hot air does, into the cylinder which is installed above the panels.

It can be positioned on a part of the roof where it will minimize the long draw off when you open a hot water tap.

DISADAVANTAGE

Water discharge for hours from the hot expansion valve, could interfere with the soundness of the roof, the system can get very hot and cause premature failure of the system.

The power to the unit can be switched of for approximately 6 months of the year, and there is no other process involved than the sun heating the water.

As you can see from the explanation above there are quite a few things to consider before you have your new hot water service. And if you think about it now when you're hot water service comes to the end of its working life it makes sense to make sure you get what you want next. A new unit can be on the wall or roof for that matter for 15-20 years if it's looked after.