McDonald’s customers may have to go elsewhere for now if they have a yen for frothy caffeinated drinks.

Melitta, the maker of the $3,000 machines used at many of McDonald’s U.S. locations, recommended a temporary stop to their use to “proactively ensure safety,” the company said Wednesday in an emailed statement.

 “We are investigating the two impacted machines. Our intent is to determine the root cause and provide a remediation plan that allows us to move forward,” Melitta said in the statement.

Melitta informed restaurant owners on Monday that it was investigating a defect in a component that could cause a blast of steam to emit, breaking the piece. It urged McDonald’s to stop using the machines for up to three weeks while it looks into the issue and inspects the machines, the Wall Street Journal reported, citing a letter to restaurant owners. 

Because the issue impacts a number of espresso-based beverages, hot and cold lattes may not be on the menu in affected locations, the Chicago-based burger chain said. 

“We have moved quickly to decommission these machines in McDonald’s restaurants and are staying in contact with our supplier to resolve the issue,” McDonald’s said in a statement. “We are still determining the scope of the impact.”

McDonald’s, which operates more than 14,000 restaurants across the U.S., continues to sell hot and iced brewed coffee, it said. The chain, which sells almost 8 million cups of coffee a day, late last year launched a spinoff eatery dubbed CosMc’s focused on coffee and other specialty drinks. 

The issue with its espresso machines is the latest headache for the chain still on the mend following a deadly E. coli outbreak likely linked to slivered onions on McDonald’s Quarter Pounders. The chain is reportedly spending tens of millions of dollars to help U.S. franchises recover from the outbreak that sickened 104 people in 14 states.