RED-faced bosses at East Lothian Housing Association (ELHA) have apologised to Tranent tenants living in a £6.5 million eco-friendly residential development for recurring problems with the estate"s heating system.

The construction of 55 affordable homes at The Hedges was completed in autumn 2007.

Its grand opening marked the completion of Scotland"s largest development of homes fitted with underground "energy-saving" heat pumps, designed to take heat from the ground to warm homes.

However, nearly two years on, residents have encountered repeated failures with the heating system and 'unacceptable delays' in repairing the problems, ironically due to its complexity.

The Courier understands that at least 11 homes have experienced heating problems since the development was completed.

One resident, mum-of-two Audrey Watson, says her heating has repeatedly broken down since she moved there in December 2007 and on some occasions she has been forced to use costly electric heaters while waiting for malfunctions to be fixed.

She said: 'Since October last year I couldn"t tell you how many times my heating has broken down - we"ve had nothing but bother.

'I"m a single parent and my daughter (14) suffers from diabetes so I need my heating to work, especially in winter.

'It drives me mad to think of going through another winter like this.' Martin Pollhammer, ELHA chief executive, admitted that, in some cases, tenants were experiencing 'unacceptable delays' in getting their systems fixed.

He said: 'The situation at The Hedges is difficult for us, and I sympathise with Mrs Watson. 'We installed 54 ground source heat pumps at this development, and commissioned a year-long study to look at their effectiveness.

'This report was very positive, but it only looked at a sample (about a third) of all the systems, none of which reported any significant problems.' However, he added: 'I don"t want to hide from the fact that we have had some problems with some of the systems.

'This has caused us problems because, unlike a regular heating system where we can call out one tradesman, there are essentially four parts to the ground source heat systems. This can mean several tradesmen visiting, and it can take too long to fix. 'This is exacerbated by the fact that we are not fully responsible for repairs on the site yet, because the properties are still under the defects period with the contractor.' 'We have taken the decision not to install more systems until we can find a single contractor who is able to install and maintain them. However, Mr Pollhammer insisted that despite its flaws 'the system can work well, saving money and saving carbon'. Regarding Mrs Watson, he explained that ELHA officials visited her home in February and found the system was working . . . but it broke down again a month later.

'The system was fully functional again in late April and we have had no reports of faults since, nor any claim for compensation.

'We are making arrangements to visit Mrs Watson again in the next few days to see what else we can do to help.'