When someone’s looking for a plumber, unless you have a good local guy you know and trust, they’re usually directed to Roto-Rooter. But why are they such a household name and the go-to company for all things plumbing? Well, for one, they’ve been around for over 75 years and invented the Roto-Rooter plumbing device. But perhaps more accurately, it runs on a very particular business model — franchising — and does it well.

Roto-Rooter, based in Cincinnati, has over 600 locations across the country. Of those, 117 are “company-owned branches,” which fall under the corporate name “Roto-Rooter Services Company.” The remaining 500+ locations are franchises, independently owned, operated and, cared for often by families who have passed the business down through multiple generations.

“Some franchises have been in the family since the 1930s,” said Paul Abrams, a Roto-Rooter spokesman. “Most families that own a franchise aren’t interested in selling. If someone doesn’t have an heir, they look to sell back to the company. Otherwise they make a good living and want to keep it in the family.”

The franchises maintain their own call centers and handle dispatch on their own. When someone calls up the company’s main 800 number, their location determines whether the call gets routed to a corporate call center (Roto-Rooter Services Company) or a local franchise office. Franchises also handle all their own training, with a field training manager designated to each location.

Roto-Rooter equips all its service techs from it’s company-owned branches with smartphones. The phones host the company’s proprietary software, which allows techs to check in, receive work orders, process credit card payments, and print receipts on the job site. Franchises are on their own, with some embracing mobile apps and others not.

But despite the differences in the two types of offices, the customer experience should remain consistent, Abrams said. All franchises and company-owned branches abide by a set of regulations, which includes everything from equipment to training to trademarks to the position of the logo on the company vans.

“Our customer service standards are all rooted in the equipment,” he said. “It’s all designed and manufactured by Roto-Rooter in our Iowa plant. Everyone is expected to live up to the rules laid out in the franchise agreement. To the customer, we’re just Roto-Rooter — whether it’s a franchise or company-owned branch.”

Abrams did point to one customer service issue he’s seen a handful of times, one that can only happen when a company is split into two types of branches: sometimes a customer will call up a franchise with a complaint and, if unhappy, ends up calling the corporate office. The problem, says Abrams, is that the corporate office is unable to assist franchise customers.

“They’ll call the corporate office and the customer satisfaction manager will say, ‘I’m sorry but your location is not a company-owned location and we don’t have any customer service authority. You’ll have to work it out with the franchise.’ Of course we want to help anyone but the way these agreements are, we just can’t. The franchises work these customer service issues out on their own.”

More: Four Tips to Keep Rock-Star Employees On Board.

Click here to download a free whitepaper, “Five Steps to Make Field Service Profitable.”