Smoke alarms in the cold

[beelzerob]

So far, both my builder and electrician have suggested AGAINST putting a smoke detector in the garage or attic area. They say that because they are unheated spaces, the cold in the winter might cause recurring false alarms. The electrician also said the dust and insulation in the attic might clog up the detector.

Has anyone else heard of this....that cold weather (let's say as cold as 0 deg F) might cause false alarms? Is there a more reliable way to protect the attic and garage then?

 

[Steve]

You usually don't want a smoke detector in those places anyway. I would look at a rate of rise heat detector like the System Sensor 5600 Series for those locations. I think they will work fine in cold weather but you can check with System Sensor Tech Support to be sure.

 

[beelzerob]

You usually don't want a smoke detector in those places anyway. I would look at a rate of rise heat detector like the System Sensor 5600 Series for those locations. I think they will work fine in cold weather but you can check with System Sensor Tech Support to be sure.

Well, if I'm going to do that...I'm already planning on putting temp sensors in the garage and attic, why don't I just use those? I can do my own temp change/min calculations and alarm over a certain rate. I guess I was just concerned that it would take a while to noticeably heat an area enough to make a difference, if something was only smoldering.

 

[Steve]

I guess you could, but usually I prefer to trust a dedicated professional product for a life safety device.

 

[beelzerob]

I prefer to trust a dedicated professional product for a life safety device.

I'll be using CQC....does that count?

 

[Steve]

For the display, sure... I was referring to the sensors, like the Elk sensor or 1 wire or whatever you'll be using.

 

[beelzerob]

For the display, sure... I was referring to the sensors, like the Elk sensor or 1 wire or whatever you'll be using.

Hehe...I know.

In the absense of anything else, I'd be using the Datanab Thermistors and I'd just add to the driver a calculation of temp change. However, I am now curious about the heat rise/135 sensors automatedoutlet has. What I need to know, though, is what kind of wiring that takes. Do things like that typically occupy the same line as the smoke detectors in the house? That would be handy. And then a relay too? Probably too much to hope for for a $15 device.

 

[Steve]

Yup, they hookup to any zone with 2 wires. Cheap, easy to install protection.

 

[beelzerob]

Yup, they hookup to any zone with 2 wires. Cheap, easy to install protection.

Soo...the 2 wires are for the relay, right? So that would be my signal to the Elk or CQC that the sensor has tripped. But is the device itself off main power and with battery backup? I suppose in a pinch, just off main power would be ok....but if a lightning strike happens up in the attic, I'd think power would be the first thing to go.

 

[Photon]

Relay? I think these devices use a fusible alloy for absolute temp and air presure closing N.O. contacts to signal on Rate of Rise. Still two-wire with EOL possible and recommended.

 

[gatchel]

If a lightening strike happens in the attic you are going to have a lot more to worry about .

 

[CORT]

I guess you could, but usually I prefer to trust a dedicated professional product for a life safety device.

Professional heat detectors are "dumb" devices that don't require power. They are simply normally open contact closure devices that trigger an alarm panel. The triggering point is built into the design of the device. And they are often one shot deals. Just for reference, heat detectors are officially not life safety devices. They should be considered as additions to a fire detection system for property protection. I fully agree with this poster that a professional product makes more sense in a fire detection system than a wired thermistor with a remote computer calculating rate of rise or temperature. There is a huge difference. You should have a mental division between fun, home automation gadgetry and a serious fire detection system. You wouldn't use any non-UL approved device to wire a switch or outlet, so why would you be any less serious about a fire detection system for your house. It sounds like you might want to give more thought to your fire detection system. Be aware of the need for fire rated cable, potentially to your keypads, siren(s), and smoke detectors. Also give consideration to the 2 wire versus 4 wire smoke detector discussion and the need for EOL relays on powered fire detection devices (signal the panel if power is lost to the devices). It gets complicated, but an integrated fire alarm panel is the only real option for large houses requiring more than 12 smoke detectors.

 

[Sandpiper]

Take a look at this thread:

thread link

 

[Digger]

For the display, sure... I was referring to the sensors, like the Elk sensor or 1 wire or whatever you'll be using.

Hehe...I know.

In the absense of anything else, I'd be using the Datanab Thermistors and I'd just add to the driver a calculation of temp change. However, I am now curious about the heat rise/135 sensors automatedoutlet has. What I need to know, though, is what kind of wiring that takes. Do things like that typically occupy the same line as the smoke detectors in the house? That would be handy. And then a relay too? Probably too much to hope for for a $15 device.

Thermal detectors can be wired to any 2 or 4 wire fire zone (on a 4 wire zone you only use the zone wires and not the power wires). Only 4 wire fire zones need an EOL Relay to monitor the power. 2 wire zones just need an EOL Resistor.

Thermals are really for use where you cant use a smoke detector (attics, garage, kitchens etc). For $15 for a device I think they are well worth it. A decent single station smoke detector is as much (I dont care for the $3.99 specials at HD etc but they are better than nothing). Most thermals have a radious of 15 to 25 feet so you wont need a lot.

The more "sensors" you have for fire detection the more time you will probably have to get out in a fire. A "Rube Goldberg" setup for life safety is not worth it in my opinion.

 

[beelzerob]

You should have a mental division between fun, home automation gadgetry and a serious fire detection system.

Sorry, I don't think that's possible. At least, not for me..... The upshot is good, though....because it's fun, then I'm interested in it, and thus I'm actually adding to what I would otherwise end up with in the house for fire safety.

Our house isn't that big...not > 12 smokes big. (geez, I hope not, those smokes are $45 apiece!)

I didn't realize that the heat detectors were basically one big heat-activated non-powered relay. In that case, this works out well. I'm already going to be running 22/4 up there for my temp sensor, which only needs 2 wires. So I'll wire up a heat detector to the other 2. Same with the garage....I'll just put it over where the cars will be parked.

Thanks, that's a relief! I wanted some kind of sensors in the garage and attic, and now I know at least that I don't need the electrician to do any of that.