Fire alarms mounted on HOUSES?

I have no idea if this is an Illinois type thing, but most if not all of the houses in my neighborhood have Wheelock EHS-DL1 horn/strobes mounted outside each house (fire lettering is washed off and the strobes are tinted yellow). Why this is I have no clue, as never have I heard them go off. Not only this, but other neighborhoods have alarms on houses as well, like Potter SH-120 and even System Sensor Spectralert Advances :shock:! Some of these alarms are found inside houses too, which is strange. Is there reasoning as to why this is?

That’s really interesting. My guesses would be:

  1. Fire/burglar combo systems may not be allowed in that jurisdiction, and the builders still wanted something that monitored for integrity to cater to higher-income, safety-conscious people
  2. A large population of Deaf people

Do they have sprinklers? Might just be 120VAC units and wired up to the water flow switch.

Yeah all the houses in my area have sprinklers.

When I went to boston I noticed every single building, from single family homes to high rises had either a bell, strobe, or red light on the exterior. I was wondering the same thing. You don’t usually see sprinkler systems in every building.

I noticed that a few houses in my area do have horn/strobes on the exterior but I always thought that meant that they were converted to businesses.


More than likely, connected directly to the water flow switch for a water flow alarm.

I would’ve said the same thing, except that he said there were NA’s inside as well. That’s not usually the case with sprinkler alarms.

Maybe it is, my grandparents live in Illinois and their house has something like that on it. I think these are actually MT4-115-WH’s. They said that they are triggered when the sprinklers in the house go off or the smoke alarms go off to alert neighbors of a fire and to call 911.

I see this a lot when I’m in the Woodstock, IL area. It’s also pretty frequent in some of the higher end neighborhoods down by Highland Park and Lake Bluff. Like Lambda mentioned, there are many residences in these areas that have been fitted with sprinkler systems.

Yeah, my grandparents are kinda around that area in some giant retirement community or something like that.

In my area, sprinklered homes have Spectralert Advances, or potter horn strobes outside.

There’s a house near me that has 2 adaptabels mounted on the eavesdrop.

There’s also a house in Leduc County with an Edwards Adaptahorn

Is it a circle or is it a square and if its a square, is it gray or red?


square, gray

My guess in most of these cases is it is a fire sprinkler alarm, probably just a 120v device tied into the waterflow switch. Every fire sprinkler system, even in a home, is required to have an outdoor alarm that sounds on waterflow. Although if they are not red, they may be for a burglar alarm system. In the days before electronic horns, bells and sometimes electromechanical horns or sirens were used for this purpose.

The horn doesn’t operate on 120VAC, it does 24VAC.

Well if its a gray square that is on the house, then it isn’t probably for a fire alarm use and more for general signaling.

Illinois resident here! I come from a town ~half way between Chicago and Rockford (You may be in the same town! PM me if you want to)



The town I come from requires all homes to have sprinkler systems. These sprinkler systems include a waterflow switch which will trip the outdoor alarm when activated.