A former door-to-door sales representative says he was encouraged to lie to homeowners to convince them to rent furnaces and air conditioners.

In an exclusive interview with CTV Toronto, a man who worked as a sales representative said he quit after a week on the job, when he learned he was lying to customers.

The man, who spoke on condition of anonymity, said he initially believed the products he rented door-to-door would save customers money.

"It's not going to save them money. Instead of seeing a decrease on their bill, they are just going to see an increase for the next 10 years," the man told CTV Toronto's Pat Foran.

"You lie to them from as soon as you open your mouth."

The man said many of the customers who signed up to rent furnaces or air conditioners from the company he worked for had no idea how expensive the long-term rentals would be.

"Over the years, they're losing $5,000 to $7,000 just to interest alone," he said.

The man provided CTV with a sales pitch guide he said was given to new employees. It included tips like telling a customer the employee is there to do a safety inspection.

It also suggested telling potential clients they are eligible for Ontario's free furnace program. The program does not exist.

"These guys will do anything to get a sale," the sales representative said.

He told CTV that some employees would go to a customer's door and claim he or she had won a new furnace. Salespeople earn approximately $900 by convincing a customer to sign a rental contract, he said.

"The highest somebody has made in a week was $17,000. Conning people, taking people's money, lying," he said.

CTV Toronto reached out to the company where the man worked, and they denied their sales representatives use company provided scripts.

The company also said any employee that lies or misrepresents themselves to a customer would be terminated.

There have been hundreds of complaints to the Consumer Ministry about the sales tactics of companies that rent furnaces and air conditioners door-to-door.

With a report from CTV Toronto's Pat Foran