Press | Published on 14th Nov 2016

COMBI-BOILERS AND NON-RETURN/CHECK VALVES- ADVICE TO INSTALLERS

With some areas of the UK increasingly under “water stress” due to rising demand and limitations on supply, the growing number of water meter installations, along with other environmental measures such as grey water recycling, are beginning to highlight a potential issue for households with gas-fired combi boilers and water heaters - particularly those where the appliance has been installed for some time

Members of The Heating and Hot Water Industry Council (HHIC) Boiler Technical group, who manufacture combi boilers and water heaters have reported an increase in customer calls arising from leakage of, or damage to, appliance components and some downstream plumbing fittings such as shower cartridges, ceramic discs in taps etc.

Problems have mainly occurred in situations where a non-return valve or check valve has been introduced into a pre-existing household water supply system, close to the point at which the combi boiler or water heater is installed. In some cases this has been associated with the fitting of an internally-located water meter.

Water UK has advised HHIC that, not all UK water companies specify the use of such valves when a water meter is fitted. However the increasing use of efficiency measures such as “grey water” systems means backflow prevention devices may be fitted with increasing frequency in future.

In view of the increasing potential for problems of this nature to occur, plumbers and heating engineers are being alerted to this issue. HHIC, in consultation with the Water Regulations Advisory Scheme (WRAS) and members of Water UK, are working together to collate some written guidance, which we hope to publish soon. Water UK have also agreed that they will ask water companies to place further details in their metering booklets or link to the guidance document from their meter application websites.