Marketing director Jon Walsh said the results of a nine-month trial in the Midlands and in forecourts and stations across the country had shown the concept had "huge" potential, with penetration at 15% after only five months.
But he admitted that repeat purchase had been low because of poor technical performance.
The Hot When You Want can heats contents through a quick-lime and water reaction in the membrane. However, the drinks did not reach a hot enough temperature in cold weather.
No date has yet been set for the products' return: "Solutions may take as little as three months but they may take a lot longer," Walsh said."