Honeywell 5820L vs 5800MICRA

When choosing a wireless window contact it is very important to consider the measurements and style of your window enclosures. Every window is slightly different. There are two types of door/window contacts: surface mount and recessed. The Honeywell 5820L is a super skinny surface mount sensor. On the other hand, the 5800MICRA is a tiny recessed sensor. They both use a normally closed built-in reed switch which is happy when the included magnet is within 1/2 inch. 

The 5820L is ideal for modern, vinyl double-hung windows for a few reasons. When you install new windows often times they come with a warranty. Drilling a recessed sensor into the window frame can void that warranty. So the extra slim dimensions (3 inch High by .5 inch wide by .8 inch deep) especially in width is a simple solution that does not require any permanent alteration of the new window. Simply peel and stick the sensor after cleaning and drying the surface. Always be sure to mount the sensor (larger part) on the casing and the magnet on the window. Another reason why the 5820L may simplify your window protection is its standard AAA battery that is designed to last up to 10 years on its first use. The MICRA requires a special coin cell battery (CR2032) which may require an extra trip to the hardware store. 

While the 5800MICRA is a recessed sensor and requires a bit more work when it comes to drilling the unit into your window, the unique coin shaped design makes it a great solution when you have little depth to work with. Its 3/4 inch diameter is nothing special but its 1/3 inch depth makes it the shallowest recessed wireless sensor on the market. Be sure to use a Forstner bit when drilling out for the sensor and magnet. Also it is best to drill out a 1/4 inch hole through the window casing so you can string the 11 inch antenna into the wall cavity. This will give the unit its best RF range.