The E8 allows the brewing temperature to be adjusted for individual coffee specialities. If the machine is producing coffee normally but drinks seem cooler than expected, check the product settings before assuming there is a heating fault. Increase the temperature setting and prepare another drink for comparison.

A cold ceramic cup can quickly pull heat from a freshly prepared drink. The E8 guidance recommends prewarming cups because a cold porcelain cup can noticeably reduce the temperature of the finished coffee. Run hot water into the cup first, empty it, then prepare the drink.

If the E8 displays Error 2 or Error 5, temperature is particularly relevant. The E8 troubleshooting information states that prolonged exposure to cold can cause heating to be disabled for safety reasons. Allow the machine to warm naturally to room temperature before switching it back on.

If the machine has recently been transported, stored in a garage or left somewhere particularly cold, give the entire machine time to reach room temperature. Repeatedly switching it on while it is still cold will not bypass its heating protection.

Limescale builds up inside the E8 over time, with the rate depending on water hardness. Complete the machine's descaling programme when requested. If a CLARIS filter is being correctly used, the E8 manages this differently and will prompt for filter replacement rather than normal descaling.

If coffee is flowing normally but isn't quite hot enough, start with the product temperature and cup temperature. If coffee, hot water and the machine's rinse water all remain cold, particularly after the E8 has fully reached room temperature, that is much stronger evidence of an actual heating problem. The user instructions don't provide an internal repair procedure for a persistent heating failure, so further diagnosis should be carried out professionally.