Internal Fire Door Closers

They cannot have a hold open feature. That is the big difference. A fire door must close automatically in a fire. If a closer has a hold open feature, someone might leave the door open. When a fire happens, the door stays open. Smoke and fire spread. That is very dangerous.

This internal fire door closer has no hold open. It closes the door every time. No exceptions. It meets GB 9398 standard. It has fire CCC certification. The fire resistance is 90 minutes or more. We put it in a 1,000°C furnace for 90 minutes. The closer body did not melt. The hydraulic oil did not leak. The door still closed.

The size is 3 or 4. Size 3 for doors 65-85kg. Size 4 for doors 85-120kg. These are the common weights for internal fire doors.

Fire doors are often in stairwells and fire exits. These areas may not have heating in winter. The temperature can drop to -20°C. Normal hydraulic oil gets thick at -10°C. The door closes very slowly. Like slow motion. Our oil is specially made. The viscosity changes less than 15% at -20°C. The closing speed stays normal.

We tested this internal fire door closer at 70°C. That is a hot stairwell in summer. We cycled the door 2,000 times at 70°C. The seals did not leak. The oil worked fine. The temperature range is -20°C to +65°C.

Do not buy this closer if you need a hold open feature. This closer cannot be modified to add hold open. That would break the fire code. If you install this on a door that needs to stay open sometimes, you will fail the fire inspection. Use this internal fire door closer only on fire doors that must close every time.

The life is 1,000,000 cycles. Fire doors do not open and close that often. But the fire inspection requires high numbers. We passed. Every closer has a CCC mark on the body. You can check it online. We can provide the type test report.

This closer is for high-rise apartment stairwells, office building fire exits, hotel fire doors, hospitals, and schools.