So there are no higher than 135 degree detectors on the approved M1 smoke detectors list?


As far as I can tell, all of the smoke detectors that are on the offficial approved list for the M1 are 135 degree. There are no higher temperature ones that can be used?

Could I expect that, if I can find one that is a Similar model number as one of the approved ones that it’d be compatible to use in the same daisy chain with others in the same group?

Otherwise, who do we connect a greater than 135 degree sensor to our M1? My garage gets hot in the summer.

Thank you,

Hi Someguy,
Smoke detectors are not approved for use in areas that may contain combustible gas (garages, mech rooms, kitchens etc.) For those locations you need to use a heat detector. They come in two temperature versions 135 degrees or 194 degrees. Heat detectors go on their own zone. They may not be put on the same zone as a smoke detector.

@dwalt :
okay, i thank you for that information. i have a few questions:

I currently have three heat detectors installed that are wired in with my smoke detectors. I'll change that wiring.

1) do these heat detectors have similar (to smoke detector) criteria that they need to meet to allow them to trigger the M1 zone? or will most any two wire heat detector work? and then i'll just program them into the M1 as "fire" or "smoke" zones?

2) are there any particular make/model of heat detectors that you would suggest for use with the M1?
I think you mean zone definition don’t you? I have three heat detectors and I’ll plan to put them in zones 28, 29, & 30 and set their zone definitions to number ten.

While we’re discussing this, I’d like to know why it is so important to have the smoke detectors on zone 16. Couldn’t they all just have their own zone (any zone) and have their zone definition set to 10? And put a 2200 EOL resistor on each one? They would all sound the alarm and the alarm would alert everyone (instead of the daisy chained smoke detectors alerting everyone)? Is there anything wrong with doing this? (Just trying to understand this stuff better. )
There are electrical codes for smoke detectors. One code is that when one smoke detector trips, all detectors in the house have to go off to alert everyone in the house. The Elk requires 2 wire smokes be on zone 16. 4 wire smokes can be on other zones. While 2 wire smokes seem simpler, I learned early on to use 4 wire smokes. Zone 16 when set as a smoke detector zone will handle the reset differently. In your scenario what would set the other smoke sounders off when one zone trips?
Well, in my scenario, one smoke detector goes off and this alerts the m1 which, in turn, causes the internal speakers to siren and say “fire fire” etc.
Zone 16 on the M1 is designed to work with 2-wire smoke detectors. It has extra capabilities to recognize an alarm condition as signaled by 2-wire smokes, and properly power the smokes when they go into alarm mode. Other M1 zones don't have that capability.

If you want to put smoke detectors on other zones, they would have to be 4-wire smokes. They use one pair of wires for power, and the other pair to signal an alarm, similar to the way a motion detector uses 4 wires.

Having smoke detectors on more than one zone gets complicated. Each zone will require an EOL resistor AND an end-of-line relay to monitor the power. With 4-wire smokes, if power is lost, the panel has no way to know because the zone doesn't see any change. The EOL relay provides a way to signal the panel that power has been lost.

Fire code requires that when an alarm sounds, it is at a certain volume, sufficient to be heard by a person sleeping in a bedroom with the door closed (at least 85 dB 10 feet from the source). Also, I believe a Temporal 3 pattern is required. I'm not sure that having the M1 announce "Fire Fire" through the speakers would meet the fire code. Your AHJ may require that the detectors themselves include sounders.

The Fire code also requires that when one smoke detector triggers, all the others will sound an alarm in a synchronized manner as well. This is done with a reversing relay that swaps the power polarity for a moment. The other detectors take that as a signal to sound an alarm. When you have a daisy chain, this is easy to do - you just reverse power on the one zone. When you have multiple zones, it requires multiple reversing relays - one for each zone.

But now you need a mechanism so that if a smoke on say zone 1 triggers, it will activate the reversing relays on all of the other zones. This can be done with M1 rules and more relays that are triggered by the rules.

Finally, resetting an alarm condition also gets complicated. To reset and silence the smokes, you need to drop power to all of them at the same time. With a single zone, you would probably use SAUX power to do this, But with multiple zones and multiple reversing relays and EOL relays, plus a smoke on each one, you may exceed the power that SAUX (or the M1) can provide. So then you need an aux power supply and another relay that you can trigger to drop power to the smokes when you do a reset smokes on the keypad.

Where problems can pop up is that while the detector on the zone that initiated the alarm is recognized by the M1 as being in alarm status, the M1 has not recognized any alarm condition on the other smoke zones. When you drop power to them as part of the smoke reset, their EOL relay drops out and causes a trouble condition on those zones. So another reset is required for those zones. This can get you into an endless loop of resets.

Many people often think it would be nice to have each smoke on a separate zone so that the M1 can tell them exactly which one caused the alarm. But in a real fire you don't care. You need to get out as fast as possible. If it turns out to be a false alarm, it is a simple matter to do a walk through to check each smoke to see which one has its LED on, indicating that it tripped.

My advice is to keep it simple with a single daisy chain.
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@RAL wow! I really appreciate the detailed explanation. you have explained it eloquently.

I will have all of my smoke detectors (2-wire) daisy chained and connected to zone 16.

so, how do heat detectors fit into this. when one goes off and it's set to zone definition of 10, this will send an alarm for the fire department but none of the smoke detectors will alarm. how is this acceptable? such tight rules (for good reason) for smoke detectors but not for heat detectors?
I use the system sensor Cosmo d4w (there is a similar 2 wire version D2W). This device sits between the security system and the smoke detectors.
This device allows any fire alarm caused by smoke detectors, heat detectors or the fire suppression flow switch to set off the sounders on the smoke detectors. It is a very reliable product. It has other features including the proper alarm for Carbon Monoxide as well and the option to use a separate power source if needed.

Please read the Amazon reviews with a grain of salt. The review from Paul is not on the Cosmo D4W but a smoke detector. The review from Kevin is about a CO detector failing. Kevin also has power problems. Notice reviewer Mark says hooking up to proper power solves Kevins complaint. If the system is installed properly, power is provided by the security system, not the house power so this should not cause a problem. I install System Sensor in every home I do. I have not had any service issues. As always, your mileage may vary.
I have a highly positive view of the System Sensor COSMO D2W. I don't have to worry about the zone used, as the panel sees it wired like a 4 wire smoke. I also have a zone for CO and a zone for Maintenance.

The system sensor sensors communicate intelligently to the COSMO the status and alarm conditions and the approrpiate zones are triggered. That said, each sensor has their own specifications. Smokes, the chambers can be removed and cleaned and returned to service. CO units have a 10 year replaceable "module" (part # CO-REPL) you don't have to replace the entire unit.

I suspect that the customer that had to pay for expensive replacements of the CO units had a less than professional installer in the Amazon review, no need for that. CO-REPL is a ~$36.00 part.

I believe a properly configured COSMO D2W and properly wired i3 and i4/COSMO System Sensors are a solid solution. Again, placement of sensors and type in your home should be directed by your local jurisdiction of authority.
Amazon reviews on this product are concerning to me.
There are a total of 5 reviews on Amazon, 2 of which are bad, and one of those is likely more due to installer issues than the product itself. I wouldn't base a decision on such a small sample.
@RAL wow! I really appreciate the detailed explanation. you have explained it eloquently.

I will have all of my smoke detectors (2-wire) daisy chained and connected to zone 16.

so, how do heat detectors fit into this. when one goes off and it's set to zone definition of 10, this will send an alarm for the fire department but none of the smoke detectors will alarm. how is this acceptable? such tight rules (for good reason) for smoke detectors but not for heat detectors?
I haven't tried a combination of heat detectors and 2-wire smokes myself, but I suspect that as with multiple 4-wire smoke zones, an alarm on one zone will not trigger the sounders on other zones unless you take some addition steps to make it happen.

@dwalt gave you one suggestion as to how this could be done.

Before we dive too far into that, it would help to know what model smoke detectors are actually installed now. Are they System Sensor, or another brand? Which model?

Also, how old are they?
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