The Potomac Electric Power Co. is launching a thermal audit service to help its customers measure the energy efficiency of their homes and learn what insuration steps can be taken to save energy and money.

The service is offered to owners of single-family homes. Pepco will also provide information about insulation contractors and how-to booklets detailing home insulation projects.

Announcements of the audits were sent to Pepco customers with their August bills.

The company estimates that it has received from 300 to 500 requests daily since then. About 290,000 families are eligible for the service.

James S. Culp, vice president of consumer services, said the audit service was instituted to help prevent home insulation fraud. He said may metropolitan resients were victimized in home improvement schemes during the mid-1970s energy crisis and that Pepco would like to prevent that from happening again.

"They know we're not a fly-by-night outfit. We're not going to disappear on them," said Culp.

Homeowners who use the audit service will first complete home information forms inquiring about heating methods, age of home, existing insulation and other questions.

"The more information we have the more customized the energy audit," said Edward J. Ryan, Pepco manager of energy applications.

The questionnaires will then be returned to Pepco and analyzed by computer. Answers will be returned in two parts: the first will evaluate thermal efficiency and the second will offer comments about energy conservation.

Later in the program, homeowners can opt to have Pepco estimators perform audits in their homes for a $25 fee.

When home improvements are needed, Pepco will help homeowners choose a contractor.

"We're suggesting that customers get bids from three contractors. Then we'll tell him how to evaluate the bids, and if he wants any help he can call us," said Culp.

"Upon job completion, the contractor will present the job form to the customer and a copy will be sent to us. We'll check on it (the completed work) afterwards," he added.

"The contractors that will be very active in our program will be the ones that agree to our terms," said Culp. "Then we'll give the complete list (of Pepco guaranteed contractors) to customers and they can get the estimates."

The company has identified 17 contractors in the area but they haven't yet signed any to the program.

The program is expected to be in full operation by mid-September, said Culp.

At that time, how-to booklets with insulation information and home insulation projects will be available.

Recently Pepco began a research project with the U.S. Energy Research and Development Administration, Princeton University students and a Chapel Hill, N.C., builder of energy-efficient homes - R. B. Fitch Jr. - using the Fitch energy monitor.

The monitor, which shows home energy cost in cents per hour, was installed in 70 area homes. Another 70 homes without monitors are control houses. The test families will be surveyed for a year by Pepco estimators and ERDA-directed Princeton students to see if the device makes people more energy conscious over a long period of time. The 70 devices, which alternately flash the time and energy cost every four seconds, were bought by ERDA.

The project is the first controlled study using the device. Dr. Lynn Collins, acting chief of ERDa's consumer motivation branch in the office of conservation, is the project director.

Fitch, owner of the monitor, said he's been installing it as standard equipment in his homes over the past year. Many homeowners using the monitor are enjoying all electric living at costs averaging a little more than $20 a month, he said, for a 1,300-to 1, 500-square-feet home.

"I find that maybe 25 per cent of the people want to save energy but 99 per cent want to save money," said Fitch.

The monitors retail for $125 and are available through the R.B. Fitch Co. in Chapel Hill, N.C.