This High altitude control unit is suitable for air heaters AUTOTERM Air 4D with a specific serial number.
Suitable for heaters with the following serial numbers:
- 4191xxxxxxx
- 4766xxxxxxx
This 12V control unit is compatible with AUTOTERM Air 4D heaters equipped with the following air pumps (assy numbers):
Heater equipped with this control unit can work at altitude up to 2500 meters above sea level (MASL).
Interchangeable control units.
| Heater | serial number | control unit | Glow plug | HA control unit | HA Glow plug |
| 4D12 | 4142…. | Assy.4144 | Assy.3333 | Assy.4002 | Assy.3333 |
| 4D24 | 4137…. | Assy.4139 | Assy.3333 | Assy.4188 | Assy.3333 |
| 4D12 | 3046…. | Assy.3048 | Assy.2288 | Assy.4002 | Assy.3333 |
| 4D24 | 3031…. | Assy.3033 | Assy.2253 | Assy.4188 | Assy.3333 |
In order to change the control unit for 4D with control units assy.3048 and assy.3033, you have to change the Glow plug as well.
