Metal Door Advice

We have some 2GIG thin door sensors installed recently on metal doors. Some work well while others are quite wonky. They get triggered without the magnet attached and have a tough time showing a solid Close each time the door is closed. Are there any best practices for how to improve the signal quality in cases like this? TIA

On a residential fire door you can often resolve with a bit of extra tape or a spacer to lift the sensor off the metal a bit, or switch the positions of the magnet and sensor. This is frequently all that is needed.

A lot of wireless door sensors will have trouble in a commercial environment though, especially if both the door and frame are metal construction. It is a difficult problem to avoid with just using a wireless sensor.

Depending on the situation a lot of times the best option is to use a wired sensor on the door and frame, then wiring it to the input of the 2GIG DW10. Program that DW10 using loop 1 for the wired input to use it as the transmitter for the wired door sensor.

Thanks Jason! A couple follow ups; Is there a recommended wired sensor to use? What is the antenna orientation on the DW10? We have some on the “pointing down” from the inner part of the frame. Does it matter whether the sensor is on the door or the magnet on the door? Many thanks in advance

Adjusting the orientation is a good first step, it doesn’t matter really whether the sensor or magnet is on the door, functionally, unless you also have a wired input, in which case the sensor needs to be on the frame of course.

You could always try a larger wireless sensor with a bigger antenna which is better raised away from the door. The Honeywell 5816 might be a good choice. Going with a wired sensor is usually the most sure-fire fix.

Any wired door sensor is fine. A surface mounted option is typically much easier to install.

A wired sensor on a metal door will ideally be a pressure or “jamb” switch installed on the hinge side jamb of the door at time of rough in . That way no magnet is involved, only mechanical compression. On a new home, this is easily anticipated. On an existing home you can “wire” a metal door by using a wireless contact with an external input by drilling the hinge side 3/8” centered centered/ insert contact/ cut drywall, connect contact and leave inside wall/ cover with blank electrical plate similar in color to wall. This might involve some drywall damage to make it happen.

A magnet will be effected by a steel door or frame. Ideally you will put the contact on the metal object and the magnet on the wood trim. The magnet will decay and lose pull over time if it’s on non magnetized steel and eventually give false “open” reports. If the magnet is drilled into the top or side of a steel door, find a 3/4” to 3/8” plastic bushing, remove magnet and re drill to 3/4. Insert plastic bushing and then a new magnet since the old one probably wore out. This spaces the magnet from the steel and helps.
Mounting the contact on steel is absolutely fine so as the contact is on the interior of the home relative to the primary alarm panel, the door acts as a huge RF antenna as long as it’s not between the contact and panel.