Hydronic heating works by circulating heated water throughout the home. The heat in the pipes then radiates into the room through wall-mounted radiators, convectors, or underfloor heating systems. Unlike other heating systems that use fans or vents to blow warm air around the room, hydronic heating heats objects through radiation, which results in an even distribution of heat.

The components of a hydronic system

A hydronic heating system consists of five components:

1. The boiler heats water to a thermostatically controlled temperature. Boilers can use a range of fuels, including natural gas, LPG, off-peak electricity, diesel, or wood pellets.

2. The piping can be made of copper, PVC plastic, or a multilayered composite. The piping carries the heated water from the boiler to the radiators, convectors, or underfloor heating coils and back again for reheating.

3. A pump: which circulates the water through the piping

4. Radiators, convectors, or the underfloor heating system, which transfer the heat into the room. Several types of radiators and convectors are available. The styles you install will depend on the layout of your home and your budget.

5. A programmable wall thermostat that controls the heat levels or room temperature to optimise comfort throughout the house. Thermostats can also provide zone control, meaning you can heat just the rooms you’re using and can set different temperatures across different zones.

How is heat transferred?

Water is an excellent conductor of heat, which is why hydronic heating is so efficient. In a hydronic system, heat is transferred into the room via thermal radiation.

Thermal radiation is the transfer of heat through the air in the form of electromagnetic radiation waves. In hydronic heating, heat emitters such as wall-mounted radiators, underfloor coils, and heated towel rails emit radiant heat to warm the room. Because objects absorb radiant heat, it cannot be blown away or moved.

Similarly, a special panel installed inside the trench is heated by the system’s hot water in trench convectors. As cold air from the room falls into the trench, it is heated by the panel and rises back into the room through the trench’s grills. As with the other heat emitters, no hot air is blown out – it is simply the hot air rising from the heated panel.

Hydronic heating operates at lower temperatures.

Hydronic heating delivers extremely comfortable heating at much lower temperatures because, without any forced air movement, the heat emitters aren’t exposed to the cooling effects of airflow, as present in ducted and split system air conditioners.

We recommend that our customers set the radiators in their bedrooms to 18 degrees Celsius, hallways to 20 degrees, bathrooms to 23 degrees, and living areas to 21 degrees. This ensures an even spread of temperature across the home that uses far less energy than many other conventional heating systems.