Vacuum Sealer Won't Seal? Start Here by Brand
If a commercial chamber vacuum sealer isn't sealing properly — the lid won't hold, the machine loses vacuum partway through the cycle, or the seal looks weak or wrinkled — the cause is almost always one of a handful of parts: the lid gasket, the seal wire, the seal bar airbag, or (less often) the main valve or pump. Start with your brand below for a full symptom-by-symptom walkthrough.
Find your brand
- Bizerba (Boss): Lid Won't Seal — Common Causes & Fixes
- Berkel and Sipromac: Won't Seal or Losing Vacuum — Common Causes & Fixes (Sipromac machines share the same models and parts, so this guide covers both names)
- Henkelman: Won't Build Vacuum or Seal — Common Causes & Fixes
- Henkovac: Won't Seal or Build Vacuum — Common Causes & Fixes
- Promarks: Won't Seal or Lid Won't Close — Common Causes & Fixes
- Webomatic: Won't Seal or Lid Won't Hold — Common Causes & Fixes
Don't see your brand?
Send us your model number and what you're seeing and we'll help you diagnose it directly: contact us. If you're replacing parts rather than troubleshooting, our replacement parts by brand guide and fit guide show what we stock for each machine. For Sipromac specifically, see the Sipromac replacement parts guide.
Not building vacuum at all?
If the machine isn't pulling vacuum in the first place — rather than sealing weakly — the pump itself may be the issue rather than the lid or seal bar. Most commercial chamber sealers use a Busch vacuum pump: see our Busch vacuum pump troubleshooting guide for exhaust filter, gas ballast valve, and coupling checks.
Lid gasket specifically?
If your troubleshooting points to the lid gasket rather than the seal wire or airbag, see our cross-brand lid gasket replacement guide for how to identify a worn gasket and find the right replacement.
Home-use (FoodSaver-style) machine instead?
If your machine sits on the counter and pulls air out through a nozzle rather than sealing inside a chamber, the fix is usually about the bag, not the machine — see FoodSaver Bags Won't Seal: Common Causes & How to Fix It.