Back Draught Damper
Made by galvanized steel,
The valve opens when overpressure occurs and closes by means of spring when the pressure drops.
Size:100mm, 125mm, 150mm, 200mm, 250mm, 300mm, 360mm and etc.
Back Draught Damper, PVA
Back Draught Damper pressure relief valve PVA is used for preventing the reverse of air flow in circular duct systems.
Backdraught dampers casing of PVA is made from galvanized steel, the blades are made of aluminium.
With a inner foam seal for better tightness and noise reducing.
The valve opens when overpressure occurs and closes by means of spring when the pressure drops.
It is recommended to install the shutter into horizontal duct.
| Model | D | L1 | L |
| 100 | 96 | 6 | 88 |
| 125 | 121 | 19 | 88 |
| 150 | 146 | 31 | 88 |
| 160 | 155 | 36 | 88 |
| 200 | 197 | 56 | 88 |
| 250 | 247 | 61 | 128 |
| 315 | 312 | 94 | 128 |
| 355 | 352 | 65 | 198 |
| 400 | 397 | 64 | 198 |
| 450 | 447 | 80 | 248 |
| 500 | 497 | 107 | 248 |





