The House members also asked the executives, who suspended marketing the kits to the public over the weekend, what their companies intended to do with any money consumers had paid for the kits and testing.

“Do you intend to refund all consumers all amounts they paid for at-home coronavirus test kits, and if so, when and how you will you do so?” they wrote in the letters. They also asked what the companies intended to do with any biological specimens that users had sent in for testing.

The rush to sell at-home kits coincided with a push by the White House to promote rapid innovation in coronavirus testing by relaxing federal health regulations. But the F.D.A. warned last week that it had not authorized any tests for purchase by consumers that involved people collecting their own specimens at home and shipping them to labs for testing.

Mr. Krishnamoorthi is chairman of the Subcommittee on Economic and Consumer Policy within the House Committee on Oversight and Reform. Ms. Porter sits on the subcommittee.

In the letters, the lawmakers also asked the start-ups what they intended to do with the specimen collection swabs that they had purchased for their at-home kits. Those products have been in short supply in many hospitals.