Merger-related expenses and some contract delays led to a decline in fourth-quarter earnings at the new Pentair Ltd., the company reported Tuesday.

Executives described the fourth quarter as unusually "noisy" because of integration efforts associated with the September merger with Swiss-based Tyco Flow Control. That move nearly doubled Pentair's size and gave it a solid presence in the oil and gas markets for the first time.

The pump-and-filtration giant has been busy shutting several of Tyco's smallest divisions, revamping its pension accounting and working to cut $90 million in expenses. The combined company is now based in Switzerland, but management still mostly flows from Golden Valley.

Combined fourth-quarter sales were $1.75 billion, up from $866 million for "legacy" Pentair. Adjusted earnings fell 16 percent to 47 cents a share, excluding integration costs. On average, analysts had expected quarterly earnings worth 44 cents a share and sales of $1.8 billion.

Including integration and other one-time costs, Pentair suffered an operating loss of $304 million or $1.31 a share, down from a loss of $1.77 a year ago.

Investors were not pleased. Pentair shares closed Tuesday at $51.35, down $1.48 or 2.8 percent.

Steve Winoker, senior research analyst at Sanford C. Bernstein, called Pentair's quarter "a bit of a mess" and "complicated." He added that the company did well operationally but that it "tried to kitchen-sink the quarter" with a host of charges and merger costs all at once. By doing so, Pentair hopes to smooth out future quarters of the newly combined company "and give it a clean slate," he said.

Winoker added that sales for the second and third quarters could rise because Tyco Flow Control's sales are traditionally strong then and because the energy and housing markets should strengthen as well.

Company officials were not put off by Wall Street's reaction.

"While many of our end markets faced some softness in the latter half of 2012, our business continued to deliver on the elements within our control, notably price and productivity," CEO Randy Hogan told analysts during a conference call Tuesday.

Hogan said Pentair weathered a "transformational year" and met company expectations. Some customers delayed orders for oil, beverage and agricultural products, but the company still performed, he said.

"Despite much of the global economic uncertainty that persists, we are seeing signs of momentum building in several end markets, such as global energy and North American residential, which combined are just under half of Pentair's revenue," Hogan said.

Pentair's largest unit, Water and Fluid Solutions, saw sales rise 1 percent for the quarter, but margins dipped 24 percent due to merger costs and different profit margins for various Tyco versus Pentair products.

The addition of Tyco brought a hefty valve and controls equipment business into Pentair and a presence in the oil and gas markets. Despite oil-project delays and weak power-industry sales during the quarter, Valves and Controls division sales rose 3 percent, thanks to an uptick in energy and industrial business, officials said.

Pentair's smallest division, the Technical Solutions business that makes electrical enclosures and thermal products, grew 1 percent in the quarter.

Pentair reiterated its 2013 guidance, saying adjusted 2013 earnings should rise 20 to 30 percent to $3.10 to $3.30 a share. Full-year sales should rise 3 to 5 percent to about $7.6 billion, officials said.

For the first quarter, officials expect adjusted earnings of 54 to 56 cents a share on revenues of $1.8 billion.

Dee DePass • 612-673-7725

4th quarter FY2012, 12/31

20122011% chg. Revenue$1,750.9$865.7+102.3 Income-273.1-174.5-- Earn/share-1.31-1.77--12 months

Revenue$4,416.1$3,456.7+27.8 Income-107.2-7.5-- Earn/share-0.84-0.08--Figures in millions except for earnings per share.