Science: First the hot air, then the fuzzy logic: Lynne Curry meets a heating expert who has made millions helping people to by-pass BT directory inquiries

Trevor Burke has had a lifelong obsession with how things work. Sitting in an office at his advertising agency, his eyes alight on a radiator. 'Wrong place,' he says. 'In fact, in a room this shape, I would have had a convector.'

Mr Burke was an excellent designer of heating systems, though he appears reluctant to admit this. His success with a small heating company in England's North-west is bettered only by his wizardry in - and earnings from - computer software.

Last month Mr Burke's personal stake in his company, PhoneLink, was worth pounds 79m. Between 22 December 1993 and 28 February this year, the joint paper wealth of he and his wife, Heather, had increased by pounds 17.6m to pounds 87.6m, mostly on the strength of their new venture, Tel-Me.

Tel-Me provides access for both the home and business computer- user to BT's database of telephone directories, plus company profiles, travel information from the AA, business findings, Press Association reports, destination mapping, weather forecasts, the British Rail timetable and postcodes. IBM has been sufficiently impressed to pre- load Tel-Me into all personal computers, using the common 486 processor (and those higher up the range). It will be launched next month with an annual subscription of less than pounds 300.

PhoneLink shares came to market in May 1993 at a value of 155p. Since then the price has rocketed. A computer magazine claimed Mr Burke had made more money than anybody - about pounds 52m - out of information technology last year.

This is serious money for somebody who can remember being strapped for school fees, but Mr Burke remains realistic about his fortune. He travels on British Rail - often using routes selected for him by his own software - and continues to work a 12-hour day.

Meanwhile, BT is planning to instal an 8,000-line fibre-optic cable network to serve his offices in Prenton, near Birkenhead. The premises are near an electricity sub- station. 'It's the only software house in the country with a 320,000-volt ring-fence around it,' Mr Burke says. 'We don't have 'keep out' notices but the real thing: 'Beware, danger of death'.'

Mr Burke says he hopes to make PhoneLink 'one of the world's most significant businesses'. 'My ambition comes from fact that I was a teenager in the Liverpool area; chasing women at the age of 14 and never being able to catch them left me with an appetite.' Fortunately, he diverted the appetite to work, capitalising on the traits that were to become his principal assets: an interest in how things work and an enthusiasm for combining disciplines.

Mr Burke says that as a heating engineer, he was 'pernickety'. His success at selling the product resulted in a request by his company to move into sales. He never lost an order in seven years and earned pounds 12,000 in 1978, mostly from a 2 per cent commission. He took a pounds 7,000 pay cut to become a director and doubled turnover in five years. With 15 months of advance orders, he had more time to dabble in computers and came up with 'the best heat-loss programme around'.

From a small desktop computer in his office flowed additional expertise on hot air. The programmes grew into Technique, a software company, and Mr Burke left heating to develop his new venture. Technique's move into kitchen-design programs resulted from a chance meeting with David Spicer.

Mr Spicer and Mr Burke toured the country for three weeks, promoting their product. When a supplier said the package was worth pounds 6,500 to his business alone, the two men knew their product would be a success. By 1987, when it was sold to its American distributor to finance the development of PhoneLink, Technique was taking orders from 3,500 manufacturers worldwide, churning out kitchen plans in three-dimensional colour and, according to Mr Burke, had a two- year head start in its market.

Shortly afterwards Mr Burke and his wife, a solicitor, developed Profile UK, a planning application service for builders and other craftsmen. A team of 64 researchers combed 430 local authority planning offices and noted down details of building projects, sifting them and sending details to 3,500 customers. Gaining telephone numbers from BT, through directory inquiries, was costing Profile UK at least pounds 100,000 a year.

After a lengthy wrangle with BT, Profile was allowed to try out BT's Phone Base, a direct-access link. The company immediately made suggestions on ways to improve the link's software.

'I said we'd like to do things with your interface, please. We'd like to make it more efficient,' Mr Burke says. 'BT went into a state of shock and talked a lot about perceptual problems. I said that their software was crap, and if they gave us six months we could improve it. After nine months we took our system back. We had developed a 'fuzzy logic' process which had a 42 per cent success rate against their 12 per cent.'

BT launched its Teledirectory service in December. For pounds 300 plus about 13p per call, subscribers can bypass directory inquiries (calls cost 38p plus VAT). PhoneLink set up DataCare to provide automated bulk retrieval of numbers for business purposes.

Tel-Me has evolved using this logic and finance raised by selling Profile UK. The Burkes own about three-quarters of the shares in PhoneLink. Trevor Burke, meanwhile, has sharpened his business acumen alongside his technological skills. 'When we sold Technique to its American distributor it had more money in the bank than I sold it for.'

Ian Woolsey, PhoneLink's production director, who has worked with Mr Burke for 12 years and developed Technique's kitchen software in nine languages, says: 'Trevor always seeks excellence with any product developed - visually, technically and functionally. It was apparent early on that he was destined to make a name for himself in the business world.

''He has an amazing capacity to absorb information and to find a new avenue for the 'front edge' of technology.'

(Photograph omitted)