Heat detector question

I just got two Notifier “Spot Fire Lowecator” 602 heat detectors. They say that they are rate of rise.


Now based on the description of this eBay auction in the last few lines, “The fixed temperature element uses a fusible alloy. When activated, the external heat collector drops away to provide quick visual confirmation that the element has operated.”

Does this mean that once this detector has activated, it permanently activated, or can it be reset?

You will only get one use.

That disc in the center will melt and drop. Once it drops, you cannot activate it. (This is only for fixed sensor. Rate of rise will be fine.)

You’re safe. I have a Model 601 – only difference is it is rated for 135 degrees instead of 200.
You can test the rate of rise sensor in two ways, though.

  1. Push up on the disc on the bottom and it will connect the contacts together, triggering the alarm. Let go and it will flex back down and be back to normal.

  2. Use a heat source – this is more difficult. I usually use a lighter but a hair dryer is good too. Keep it a foot away so you don’t heat up the fixed temperature element. Take away the heat source as soon as the detector activates. It is important that you do not keep the heat on the detector long because of the potential to melt the fixed temperature sensor.

Also, how would I wire it up? I just use + and - for my system.

It wires the same as a pull station.

be careful doing the “push up on the disc” trick. I’ve damaged a mechanical heat doing that.

What you have is a chemetronics heat detector. I haven’t tested mine in years, but I think I used a hair dryer or heat gun. you have to be very careful, too much heat will blow the FT element. hold the heat source more to the outside of the detector rather than at the disc. what markings are on the collector disc? A circle and/or a dot?

A dot in the middle.

a dot in the middle means it’s fixed temp only - there is no rate-of-rise detection in this.

a circle means the FT element is set at 200 degrees instead of the usual 135 degrees.

A circle with a dot means it’s a 200 degree fixed-temp only unit (no ROR).

This can’t be tested, the only way it will activate is with the FT element which destroys the detector. I wouldn’t give this any heat source.

Derp. I failed. This is the manual I found online. You’d know more about it than I would. The detectors have a ring!


What you have there is a 200-degree fixed-temperature detector. That is the slowest type of detector to respond in a fire, as it doesn’t even have rate-of-rise. The only practical place for those is attics (that I can think of). At 200 degrees in an average room fire, you’re in bad shape.