| Company name | Reg. code |
|---|---|
| HEATANGO OÜ | 17125415 |
| HEATING MASTER OÜ | 12379571 |
| GEOTHERMAL HEATING OÜ | 16571207 |
| HEATING SYSTEMS OÜ | 12956749 |
| SMART HEATING OÜ | 16247814 |
| HEATING EXPERT OÜ kustutatud | 11302187 |
| ESTONIAN HEATING OÜ (former name Eesti Küte OÜ) | 11551654 |
| HYDROGEN HEATING OÜ kustutatud | 12817663 |
| URBAN HEATING OÜ | 14276131 |
| RE HEATING OÜ kustutatud (former name Puitkütte OÜ) | 12702581 |
| HEATING WAYS OÜ | 14071274 |
| BALTIC HEATING OÜ | 16216067 |
| BALTIC HEATING TECHNOLOGIES OÜ kustutatud | 11332372 |
| MAMAKO HEATING SYSTEMS OÜ kustutatud | 11678538 |
| INNOVATIVE HEATING SOLUTIONS OÜ kustutatud | 14235056 |
| BALTIC HEATING GROUP OÜ | 10840089 |
| EURONOM HEATING SYSTEMS OÜ kustutatud | 12104035 |
| BALTIC HEATING SYSTEMS OÜ | 11091951 |
| UGO GAS HEATING SYSTEM OÜ | 10540743 |
| ETANGO LALAPANZI OÜ kustutatud (former name Igera Buss OÜ) | 11404137 |