UKWTA fears pouring boiler condensate down UK’s drains may risk the nation’s health and is calling for government-backed research.
Fears surrounding the knock-on effect of pouring condensing boilers' condensate (low level acidic water) into Britain's drains, have been raised by more than 100 members of the UK Water Treatment Association.

Condensate is increasingly making its way into UK drains and soakaways, following the government's decision to require all new domestic boilers be SEDBUK A or B rated.

Now that all new boilers installed in homes must be condensing and condensing boilers account for more than 50% of the sales in the commercial sector, the volume of condensate is only set to get bigger.

'We know that the condensate generated by the growing numbers of condensing boilers installed across the UK is low level acidic discharge. However, considering the age of much, if not most, of the drainage infrastructure and the huge quantity of condensate being discharged without treatment to the sewers, it seems a question we should ask and one we should consider having a viable response to, in case we discover that it is causing a problem,' says UKWTA technical director Tony Frost.

Tony Frost also expressed concern about the possibilty that drinking water could be affected which therefore required careful attention by the government.

Frank Rogalla of Black and Veatch, a multi-national sewage water and energy engineering services company, said 'My gut reaction is that this is a small drop in a rather big stream.'

A condensing boiler from an average household will produce approximately 800 litres of acid per year at pH4 level.

'The average household produces 800 litres of water a day' he added.

As more condensing boilers are installed, conservative estimates suggest that in two years time, 50 million litres of acid at pH4 could be added to UK drains each week.

'The fact that several manufacturers have introduced condensate neutraliser products would suggest that the concern is wider spread than might initially be thought,' said Frost.

'The environmental consequences are potentially huge and, until now, little interest has been shown in addressing the potential problem,' he added.