UK Manufactured Unvented Hot Water Cylinder Installation Guide
9
HWA Charter Member
Joule are proud to be a charter member of the the Hot Water Association (HWA), that 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 improve-
ment 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
Water Supply
The performance of any unvented system is only as good as the mains water supply available. To this effect
the maximum possible water demand should be assessed, with the knowledge that the mains supplies both
hot and cold services simultaneously. The water heater itself operates at a pressure of 3bar, controlled by the
inlet control set, and is capable of delivering over 50 litres per minute. The high quality inlet control set has been
designed to make the most of the low rates available.
The water supply should be checked to ensure it can meet these requirements. If necessary, consult the local
water authority regarding the likely pressure and flow rate availability.
Consideration should be given to upgrading existing 1⁄2” (15mm) cold mains pipework to a larger size if
the recommended minimum pressure / flow rate is not being achieved. JOULE recommend that primary
pipework used has a minimum diameter of 22mm to ensure low pressure loss.
A high static (no flow) mains pressure is no guarantee of good flow
availability. In a domestic installation 1.5bar and 25ltr/min should be
regarded as the minimum. The maximum mains pressure that the inlet
control set can cope with is 10bar.
