UPDATE 2-United Tech beats Street, lifts forecasts again

* Forecasts 2017 adj. EPS of $6.58-$6.63

* Ups low end of 2017 sales forecast to $59.0 bln from $58.5 bln

* Keeps organic 2017 sales growth unchanged at 3-4 pct (Adds background, details on unit sales, updates shares)

Oct 24 (Reuters) - United Technologies Corp's quarterly profit topped analysts' estimates, driven by higher sales in its Pratt & Whitney business, prompting it to raise its 2017 adjusted profit forecast for the second time this year.

Shares of the company, which also makes Otis Elevators, were up 1.7 percent at $122.90 before the bell on Tuesday.

United Tech raised its 2017 adjusted earnings per share forecast to $6.58-$6.63 from $6.45-$6.60. The company also increased the lower end of its sales forecast range to $59.0 billion from $58.5 billion, and kept the top end unchanged at $59.5 billion.

Sales in the company's UTC climate, controls and security business, its largest unit, which makes Carrier air conditioners and fire detection systems rose 6.2 percent.

United Tech's second-biggest business, Pratt & Whitney, which makes aircraft engines, saw a 10.6 percent jump in revenue.

However, the company's profit margins narrowed as it continues to face slowing sales of Otis Elevators in China, due to excess market supply.

United Tech is also spending on accelerating production of its fuel-saving geared turbofan aircraft engines that power Airbus SE's newest narrow-body jet, the A320neo.

The company said its segment operating profit margin fell to 14.5 percent in the third quarter ended Sept. 30 from 15.9 percent, a year earlier.

United Tech's income from continuing operations attributable to shareholders fell to $1.33 billion, or $1.67 per share, from $1.44 billion, or $1.74 per share, a year earlier.

On an adjusted basis, the company's earnings per share rose to $1.73 from $1.76.

Net sales jumped about 5 percent to $15.06 billion.

Analysts on average were expecting third-quarter earnings of $1.69 per share and revenue of $14.98 billion, according to Thomson Reuters I/B/E/S. (Reporting by Ankit Ajmera in Bengaluru; Editing by Martina D'Couto)