Installing the Glynn-Johnson SensaGuard 280 Holder/Release

Feb. 1, 2010
This self-contained, 9-volt battery operated door holder with built-in release mechanism provides a wireless method for propping open a fire door.

Sometimes it is better to keep an interior door propped open because of the amount of foot and cart traffic, than to force everyone to open the door. Unfortunately, because of code requirements, fire doors cannot be held open using a door closer with hold-open function, a door stop or drop down doorstop. Attaching a door- mounted doorstop onto a fire door is against code. If the door closer has hold-open, the closer must be removed and a non-hold open closer installed. If there is a drop down doorstop, remove it and re-attach the screws to fill the holes.

Always contact your local Authority Having Jurisdiction (AHJ) before installing any product onto a fire door.

There are several options for propping open a self-closing fire/smoke barrier door. The most common method is the use of hard-wired magnetic door holders. A magnetic door holder is an electro magnet, 12 or 24Volts, that is mounted into the adjacent wall and wired into the building’s fire alarm panel. A metal plate with swivel is mounted onto the door. When the door is open, the magnetic door holder aligns with the door mounted metal plate. Power is provided to keep the magnetic door holder energized, which magnetically holds open the door. When a smoke alarm detects fire or smoke, power is automatically cut, the magnetic holder releases and the door closer swings the door shut.

Most magnetic door holders are installed during construction as the cost to retrofit can be expensive, depending upon the distance the door is located from the fire alarm panel.

A wireless method for propping open a fire door is the UL Listed Glynn-Johnson SensaGuard™ 280, a self-contained, 9-volt battery operated door holder with built-in release mechanism. The surface-mounted SensaGuard 280 was developed as a standalone retrofit product that has a built-in battery powered smoke detector that operates the mechanical door holder. The SensaGuard 280 is compliant with the NFPA 101 Life Safety Code Article 5-2.1.8 Self-Closing Devices, Exception C, 2. The State of California Fire Marshal Listing and with UL listed door closers.

The Glynn-Johnson SensaGuard 280 is designed to operate with a fire rated door closer. This smoke detecting door holder and release mechanism is installed onto the secure side of the door to provide protection. When smoke or particles of combustion are detected in the ionization chamber, the door holder is released. The door closer closes and latches the door. Depending upon the configuration of the doorway, the SensaGuard 280 hold open function is adjustable at a single point from 90 to 180 degrees when mounted onto the Push Side of the door or from 90 to 130 degrees when mounted onto the Pull Side of the door.

The one-piece SensaGuard 280 is approximately two feet long, two inches wide and about two inches tall. On one end has the microprocessor-controlled holder mechanism; the other has the battery compartment, smoke chamber and controls. In between is the slide block track.

The SensaGuard 280 has two recessed labeled buttons on the surface, “Test” and “Reset.” The “Test” button tests for proper operation of the release mechanism. When this button is pressed and held for two seconds, the slide block is released, allowing the door closer to close the door. The “Reset” button is used to reset (re-arm) the holder after testing or after smoke was detected in order to re-arm the holder mechanism. The “Reset” button must be pressed in order for the slide block to be retained.

To resist vandalism and unauthorized changes, the SensaGuard 280 has tamper protection using a fail safe switch mechanism for the battery compartment. If the cover is removed, the slide block automatically releases. To ensure proper operation and to indicate sufficient battery voltage, the LED flashes once every 40 seconds. Should battery power drops below 7.2 volts, the slide block automatically releases.

Like the magnetic door holders, the SensaGuard 280 can also be manually released for times when the door needs to be closed and then opened by pressing the “Test” button. There is a Hold Open Tension Adjustment Screw. Turning this screw clockwise increases the holding force on the slide block.

Prior to installing the SensaGuard 280, the instructions indicate to install the 9 volt battery and ready the unit for operation. Once the battery and cover are installed, press the and hold the “Reset” button for two seconds. The motor should momentarily run. The LED should flash once every 40 seconds.

Installation of the Glynn-Johnson SensaGuard 280 is not difficult, the unit is mounted onto the secure side of the door. For push side installations, the unit is mounted beneath the jamb stop using three mounting screws. When installed onto the pull side of the door, the unit is mounted onto the face of the jamb using two long mounting screws. The arm bracket is designed to be mounted onto the door using the supplied sex bolts.

The SensaGuard 280 can be installed on door equipped with concealed and surface-mounted door closers. The unit is designed to be mounted onto the side opposite a door equipped with a surface mounted door closer.

For this installation, the closer is on the opposite side of the door. We installed machine screws. If not, the door closer would have to be removed and reinstalled with the possibility of having to make modifications to accommodate the sex nuts. The second, more important reason is that the door has reinforcement to accommodate the door closer on both sides. Threading machine screws through the door skin and the reinforcement is sufficient to properly connect the arm bracket.

To determine the location of the arm bracket, measure the “A” dimension for the first hole in the arm bracket, down 2-5/8” from the header stop. To simplify drilling and tapping, Lawson Regency Combination Drill-Tap was used to install the arm bracket. The forward portion of the ¼-20 bit is ground as a high speed twist drill. The middle portion of the drill is machined to tap the hole. The Made in the U.S.A. bits have a reduced neck for additional clearance and a 118-degree spiral point.

For this installation, the door was open a little more than 90 degrees. This is sufficient to not contact the rear wall, but open enough to provide easy access and egress. For 180-degree installations, reposition the arm bracket onto the hole closest to the hinge to accommodate the longer reach. For the 90-degree installation, no change is required.

Install the arm bracket onto the door. Open the door, making sure the slide block moves into the latched position. Press the “Reset” button while holding the door open. The slide black should be held in place. If not, adjust the hold-open tension adjustment screw clockwise.

Press the “Test” button to release the slide block. If it does not release, adjust the hold open tension a

djustment screw counterclockwise. The door closer should close and latch the door. If not adjust the door closer.

After each test, open the door and press the “Reset” button. Test this operation several times.

Once the unit is installed, test the electronics by lighting a match beneath the ionizing chamber. The slide block should automatically release and the door should close. A held open door will release automatically when smoke is detected. It is necessary to push the reset button after the smoke clears the chamber. This will re-arm the holder mechanism.

To ensure fail-safe operation, the SensaGuard Series 280 automatically releases the door when battery power drops below 7.2 volts or if the battery cover is removed.

The Glynn-Johnson SensaGuard Series 280 is available in a US28 clear anodized aluminum and 313AN Dark Bronze anodized aluminum finishes.

For more information, contact your local locksmith distributor or Glynn-Johnson, 2720 Tobey Drive, Indianapolis, IN 46219. Telephone: 877-613-8766. Technical Support 888-371-7331. Web Site:

For drill-tap information, contact Lawson Products Inc., 1666 E. Touhy Ave., Des Plaines, IL 60018. Telephone: 866-529-7664. Web Site: