Certification organization North American Technician Excellence is starting an online campaign to educate homeowners on the need to use contractors certified by the group.

Starting in April, ads will appear on business reviews website Yelp.com. When visitors search for heating or air-conditioning services, advertisements will pop up that say “NATE-certified technicians can help their A/C system run smooth all season long” and direct them to the NATE website www.hvacradvice.com.

The contractors featured on the advice site are part of NATE’s Consumer Contractor Connection program, which means at least half of their technicians are certified. Those who have 80 percent or more certified are featured as Quality Circle contractors and can be listed free on the website.

“As an increasing number of homeowners learn about NATE and visit HVACRAdvice.com to find a qualified local contractor, it’s more important than ever for contractors to insist on NATE-certified technicians and to include their company information on the site’s online locator,” said NATE board Chairman Don Frendberg.

“Campaigns like these extend the reach of our message to a greater number of homeowners, educating them about NATE certification and helping to connect them with contractors who are dedicated to superior installation and service.”