Indirect Solar Hot Water Heating System


In an indirect heating system, water is heated through the transfer of heat from a circulating heat transfer solution (glycol).  It is this solution that is heated in the copper tubes within the solar collector panel. A heat exchanger is then put in the hot water tank to heat the water


Typical System Components


A typical Solar Water Heating (SWH) system comprises of the following:


An Insulated hot water storage tank  


Its capacity is specified in litres to determine the number of collector panels to be installed. There are inlet and outlet connections for the flow of water to the copper tubing in the collector panel. It may include an immersion heater for boosting hot water system in an integrated system for domestic use.


A Solar collector panel  


The collector panel is an outdoor solar energy absorption component usually installed on the roof as per the direction of the sun. It’s made up of the following parts:


Collector frame; this holds the entire panel such that its surface is fully exposed to the sun.


Glass panel; it’s transparent to allow a high level of light penetration and to withstand harsh weather conditions.


Receptor panel; its usually black, it absorbs the heat energy and in turn heats the copper tubes containing glycol for indirect systems and water for direct systems.


Insulation; prevents the loss of heat by conduction or convection on the lower side of the panel.


Installation kit 


This has accessories that aid in connection of pipe work between the collector panel and the tank.



Direct Water Heating Systems

These systems circulate the main household water supply between the collector and the storage tank. When the water

in the collector becomes warm, convection causes it to rise and flow towards the hot water tank. They are also not suitable for hard or acidic water due to mineral deposits and corrosion of the panel.

Installation kit

This has accessories that aid in connection of pipe work between the collector panel and the tank.