In 2010 and 2018, the UK experienced prolonged spells of sub zero temperatures down to -20°C and below in many areas. This resulted in a significant increase in the number of calls to boiler manufacturers and heating engineers from householders with frozen condensate discharge pipes.
British Standards, Building Regulations and industry guidance currently advise on how condensate discharge pipes should be run, either internally or externally, or a combination of both and Wolseley are here to help to summarise the best options to avoid freezing.
When fitting or replacing a boiler, the condensate discharge pipe should be connected to an internal ‘gravity discharge point’ such as an internal soil stack (preferred), internal kitchen or bathroom waste pipe such as a sink, basin, bath or shower waste.
External pipes from sink wastes or washing machine outlets should be a minimum of 30mm internal diameter, insulated with waterproof UV resistant material, terminated below the grid but above the water line and a suitable drain/leaf guard fitted. The end of the waste pipe should be cut at 45 degrees where it terminates into the grid to help reduce the potential for the pipe to freeze.
Where it’s not possible to connect the boiler condensate discharge pipe to an internal ‘gravity discharge point’, a condensate pump should be used, connected to a suitable internal connection point such as an internal soil stack (preferred), internal kitchen or bathroom waste pipe such as a sink, basin, bath or shower waste.
When servicing or repairing a boiler, check any boiler installations, especially those that have external condensate drains, to see if they can be terminated internally or upgraded to the latest guidance.