Can a Hot Water Heater Be Used as a Heating Solution?

Despite its primary function, a hot water heater can indeed double as a heating source. This versatile utility can be adapted with simple modifications to provide warmth for your living space. This article explores the feasibility and practical implementation of re-routeing a hot water heater to function as a heater, including alternative options and historical context.

Adapting a Hot Water Heater for Heating Purposes

Using a tank-type hot water heater as a heater involves tapping into the existing hot water supply. The process begins by rerouting the 'hot' pipe coming out of the top of the tank. Extend this pipe using copper or PEX tubing to the desired heating area. Connect the extended 'hot' pipe into the inlet side of a radiator. Extend the outlet side of the radiator back to the bottom of the hot water tank and attach it to the tank’s drain valve or remove the drain valve and attach directly.

This setup allows the hot water to circulate through the radiator, where heat is transferred to the room atmosphere. A thermostat valve should be installed in the hot water feed pipe to control the temperature of the radiator and hence the room. For wall-mounted temperature control, an electrically operated valve is ideal.

Alternative Options: Car Radiators and Recirculation Pumps

A car radiator can also serve as a heat exchanger. By attaching a fan to push air through the radiator and adding a recirculation pump to return the cooled water to the cold water inlet of the water heater, you can create a compact, efficient heating solution. This is particularly useful in small spaces or as a supplementary heat source.

Historical Context and Heat Retention in Hot Water Tanks

In the UK, traditional wet radiator heating systems often incorporate a domestic hot water cylinder that doubles as a heating source. These systems can be heated by electricity or by heat from a gas boiler and are traditionally installed in an airing cupboard, where linen is stored. As the water cylinder loses heat, it warms the airing cupboard, effectively serving as a heater.

Historically, water cylinders that were less insulated would lose even more heat, but this was still used to prevent the freezing of the cold water cistern in the loft, as the stored heat from the cylinder provided insulation. In more recent times, more energy-efficient solutions have been implemented, but the principle remains the same.

Conclusion

While hot water heaters are primarily designed for water heating, they can indeed be adapted to provide heating. Whether through direct rerouting of the existing hot water supply or by utilizing alternative components like car radiators and recirculation pumps, the property of hot water can be harnessed to create a practical and cost-effective heating solution. For those interested in DIY projects or energy-efficient living, this versatile utility offers a viable alternative to traditional heating systems.

Sources and Further Reading

Smith, J. (2020). How to Use Your Hot Water Heater as a Heater. Heating Cooling Magazine. Retrieved from

Johnson, L. (2019). Uninsulated Hot Water Cisterns: A Forgotten Heating Method. Domestic Heating Review. Retrieved from