Eberspacher Airtronic D2 25 2069 diesel 34W 12volt 2,2Kw heater 863515BC and the 30100154 controller thermostat module needs to be replaced. What is an updated unit that works?

With the 25 2069 heater we would require to learn if it is H Kit compatible prior giving 100% best advice. Perhaps you could email a photo of heater dataplate to sales@butlertechnik.com if you are unsure.

For integrated temperature sensing solution on both Hkit and pre Hkit you could opt for an 802 SERIES controller as below

https://www.butlertechnik.com/item/Eberspacher/Airtronic-802-Modulator-Controller-for-Airtronic-D2-D4-S2-M2-80210003/62W

For greater choice though please let us know regarding the HKit

Thank you