The Hot Water Association (HWA) has been formed through the union of the two UK industry trade bodies, WMA (Water heater Manufacturers Association) and MODUS (Manufacturers Of Domestic Unvented Systems).
The objectives of the HWA are "To be recognised as the leading body in domestic hot water storage and, through cooperation and partnerships, to support, drive and promote the sustained growth and improvement of standards within the entire domestic hot water industry".

The HWA operate a Charter that all members of the association observe.

The HWA Charter Statement requires that all members adhere to the following:
• To supply fit for purpose products clearly and honestly described
• To supply products that meet or exceed appropriate standards and building and water regulations
• To provide pre and post technical support
• To provide clear and concise warranty details to customers