NETWORK Rail has admitted the IT system that runs one of the key facets of the multi-million pound overhaul of Waverley Station is so ridden with faults it is being replaced entirely.

Six escalators were built as part of a £7million project to overhaul the historic Waverley Steps entrance on the north side of the Edinburgh station but have seen barely a day go by without one of them being out of order since opening to the public on January 30.

Network Rail, which owns and manages the station and has overseen the development project, has blamed a software glitch for repeated breakdowns of escalators installed at Edinburgh's Waverley Station just over a month ago.

Network Rail initially blamed a faulty part after the escalators broke down after just one day.

But it has now confirmed the IT system that runs them will have to be replaced.

A Network Rail spokesman said: "We have been addressing problems with the software on the escalators. We regret the inconvenience caused to passengers and are working to restore full use of the new escalators as quickly as possible."

One user said: "It has been very frustrating. Virtually every day one of the escalators is taped off and out of use. It has certainly had its fair share of teething problems. They are a fantastic feature, so let's hope this can finally be sorted out."

Before the escalators were installed, passengers had to negotiate 72 steps to reach the station concourse and were frequently buffeted by the weather because of a wind-tunnel effect.

The overhaul has seen the steps narrowed to make way forthe escalators as well as installing a glass ceiling and entrance at the top.

One of the problems with fixing the escalators has been their heavy usage, with the station open for all but a few hours in the morning, limiting the opportunity for repair work to be carried out, a source at Network Rail said.

Before they closed last February, the steps were used by around 14,000 people a day and more were expected to use them following completion of the development.

The project is part of a £130m investment in Waverley, one of Scotland's busiest rail stations, which will have 34,000 square metres of glass roofing replaced, a new entrance built at Market Street, a refurbishment the station concourse and main building exterior and many other cosmetic improvements.

The steps, which have been in use for 145 years, were supposed to be redeveloped five years ago but the project was held up by objections and the use of untested legislation introduced in 2007.

They have narrowed to just over half their width, with three banks of adjacent escalators providing a new option for the 40ft ascent.

In a separate part of the project to be completed in July, two 16-person lifts will take passengers between the station and mall roof, with a ramp up to Princes Street.

The lifts have been re-sited away from the steps following an objection from the Balmoral Hotel over their impact on views of Edinburgh Castle.