About Hot Water Types
First: What is Hot Water Heating?
Water heating is a thermodynamic process that uses an energy source to heat water above its initial temperature. Typical domestic uses of hot water include cooking, cleaning, bathing, and space heating. Hot Water has many uses.
Domestically, water is traditionally heated in vessels known as water heaters or hot water tanks. These metal vessels that heat a batch of water do not produce a continual supply of heated water at a pre-set temperature. The temperature varies based on the consumption rate, becoming cooler as flow increases.
The 2 main Tank-Type Water Heaters
The standard water heater comes in two types, Electric and Gas. Gas fired units have a vent pipe at the top to carry away exhaust gases. Electric models on the other hand, simply have a power cable that connects the heater to your electricity supply.
The job of the tank-type heater is not only to heat the water, but to store it until it’s ready to use. Therefore, in addition to the tank’s heating system, every tank is equipped with insulation to help keep the water warm between heating cycles.
For safety, all water heaters are equipped with a T&P valve (temperature-and-pressure relief valve). This valve opens if either the temperature or pressure of the water exceeds a safe limit.
Most tanks are made of steel, which is glass-lined on the inside to help prevent corrosion. In fact, corrosion is the primary reason that tanks fail. Once rust produces a hole, there are temporary fixes, but the tank should be replaced. All tanks also have an anode rod to control corrosion. The magnesium anode rod protects the tank by corroding in place of the steel. Electric vs Gas infographic below:
Tankless Heaters (Electric & Instantaneous)
If your home doesn’t have a hot-water tank, you probably have a hot-water or steam home-heating system that also heats water for your taps. To accomplish the job, your boiler has a tankless water heater. In this system, a coil of pipe is connected at one end to the cold water supply, and at the other to your hot-water delivery piping. As the boiler heats the water that warms your home, that water heats the coil, creating hot water at your taps.
Because tankless heaters only heat water as it’s used, there’s no cost for maintaining heat in a large volume of water during periods of low usage. Like tank-type heaters, tankless heaters are designed to achieve a specific heating rate. In addition to boiler-mounted tankless heaters, stand-alone units are available.
Gas-fired instantaneous water heaters utilize a coil and heat exchanger to heat water as it’s required. Like boiler-mounted units, instantaneous water heaters don’t use energy to maintain the heat in a volume of water, but only fire as hot water is required.
Solar hot water in Australia
Everybody knows solar hot water is heated using natural energy from the sun. Solar energy heats up large panels called thermal collectors. The energy is transferred through a fluid (often water) to a reservoir tank for storage and subsequent use. It is then used to heat water for domestic use and also as an energy input for heating devices and applications.
Bexley Hot Water Repairs is motivated by the desire to reduce energy consumption more specifically, to reduce a significant source of greenhouse gas emissions. Bexley Hot Water Repairs recommends converting from electric to solar hot water and this could save 20% of the state’s total greenhouse gas emissions.
Despite an excellent solar resource, the penetration of solar water heaters in the Australian domestic market is less than 10%, with new dwellings accounting for most sales.
During the 1950s, Australia’s Commonwealth Scientific and Industrial Research Organisation (CSIRO) carried out world leading research into flat plate solar water heaters. A solar water heater manufacturing industry was subsequently established in Australia and a large proportion of the manufactured product was exported. The Four original companies are still in business.
Water heating is the largest single source of greenhouse gas emissions from the average Australian home, accounting for around 28% of home energy use (excluding the family car). The Australian government estimates that installing a climate friendly hot water system can save a family $500 to $1000 per year.