OLD TOWN – There is no visual proof of activity from the low temperature heat pump manufacturer that promised to bring hundreds of jobs to the former Georgia-Pacific Corp. mill, but the intent to set up a commercial operation at the site still is in the works.

Hallowell International Heating and Cooling Systems was one of the first companies to sign on to the Old Town site when the mill was closed by G-P and later purchased by Red Shield Environmental LLC, a group of private investors.

The testing, production and sale of residential heating and cooling units is well under way at the Bangor base, and the commercial unit is being validated for performance and safety, Hallowell President and Chief Executive Officer Duane Hallowell said Tuesday.

“Everything is by the book,” he said.

Hallowell has turned a city-owned building at 110 Hildreth St. in Bangor into a manufacturing, assembly and heat pump distribution facility.

He has a strong commitment to keep residential operations in Bangor, but once the commercial unit is ready for sale, it will be manufactured at Red Shield.

Hallowell is expected to use the old conversion area of the mill where large rolls of paper products were turned into smaller versions that consumers found on store shelves.

“I expect within the first of the year we’ll start setting up manufacturing capabilities [in Old Town],” Hallowell said. “We try to keep everything in check so that we grow smart.”