Water is heated, on demand, using a burner and exchange system, ensuring a constant, reliable temperature.

What is a continuous flow hot water system?

A continuous flow hot water system is a process of delivering a continuous flow of hot water at a constant temperature, without the need for storage. Continuous flow will only ever utilise energy whenever heat is needed. I.e. the opening of a shower. With the most advanced systems the user will be able to set the desired temperature of hot water required to suit their needs therefore vulnerable users such as child and the elderly can be safeguarded from the risk of scalding.

Continuous flow technology can be the most efficient method of supplying hot water when used as a standalone system or when used in conjunction with different forms of renewable technology.

How do continuous flow water systems work?

Cold water is fed into the unit by the cold water inlet, when a hot tap is opened and the water starts to flow, a burner is immediately ignited and subsequently heats up the cold water passing through the heat exchanger.

This process of heating the water happens instantly and delivers a constant flow of hot water at the desired set temperature. The ignition process is electronic, thus there is no need for a standing pilot light therefore energy is only consumed when hot water is required.

Advanced systems can deliver water within +/- one degree of set point. As there is little or no storage of water within the appliance therefore energy loss is near zero, when compared with hot water storage systems.

Continuous flow systems are powered by the consumption of NG or LPG which are amongst the most efficient forms of energy available.

What types of continuous flow hot water systems are there?

Continuous flow water heaters vary in capacity and application.

The majority of water heaters are mounted internally with a suitable flue arrangement or externally without a flue. Capacities range from that required for residential applications, light commercial application through to commercial and industrial installations, in either single or modular unit arrangements.

The capacity of any hot water system is determined by the number of hot water outlets and and usage.

What are the pros and cons of continuous flow hot water systems?

Advantages Disadvantages
Continuous flow of safe, temperature accurate hot water Limited capabilities to satisfy peak hour demand
Energy is only consumed when a outlet is opened Lower performance from prolonged exposures to poor quality untreated water
Space saving as there is no need for water storage Consideration needs to be given to available gas supply
Low maintenance cost  
Flexibility of usage - multiple applicance systems can be utilised to supply greater hot water requirements (modular)  
Near zero energy losses  
Fast recovery time  
Direct mains fed