Brooks EIB3016

This alarm (which you will probably need to buy from an electrical supplier) costs about twice the ones from the big green box. If you are getting false alarms, try this one. It feels much more solid than the cheaper Asian imports. It fits the same (3.5 inch centre) mounting holes. It has much better circuitry. The phone app to check everything about the alarm is very effective. My only criticism is that it says “that operational life is 10 years from installation, but it is really 10 years from manufacture. The guarantee is 5 years.

[b] Why Do Photoelectric Smoke Alarms Fail So Much? (& How to Fix It) [/b]

Take the common case of a cheap 240v photoelectric smoke alarm with a 10-year lithium back-up battery and a 10-year guarantee. In my area (coastal NNSW) these often fail after about a year, due to multiple false alarms. Read the reviews - every cheap imported brand has the same problem. Of course, if the device is detecting smoke or steam from your cooking or anything else, it is not a false alarm! If there is smoke, the alarm must sound to save lives.

One probable contributor to false alarms is that these devices are mounted to the ceiling, with holes for 240v wiring and mounting, through which falls the dust and small critters in the roof space. Quality units come with a mask that blocks this ingress. But there are plenty of side-slots, and a light that attracts insects through those slots. Insects will fly through, even if you wipe the device with a repellant. Spiders chase the insects. Sure, there is a grid around the sensor, but it has to be open enough to allow plenty of air exchange - otherwise it cannot detect smoke.

The base of the mounted alarm is solid - anything that falls inside stays inside. Hmmm, maybe they would work longer if mounted to a wall; but that is not the ideal location for smoke detection.

After some time; all that dust, fluff, spider web, and insect bits build up inside the alarm. Then a slight breeze is enough to stir some up, or a little spider goes exploring. In some combination with other residues, high humidity and control ripples in the power supply, this is enough to set off the alarm (usually at 1-3 am).

The instructions say to clean the alarm out frequently with compressed air or vacuum. Who has compressed air at home? A vacuum will suck out some of the junk, but not all.

So what can you do? It is no use complaining. This is not entirely a manufacturing fault. Nobody has worked out how reliably to detect smoke in a home without false alarms at that low price. The regulations do not mention false alarms. Humidity control and power filtering are expensive, and you can not be sure in advance which one(s) will help. It will be much cheaper to buy a higher-quality smoke alarm with more sophisticated circuitry. A battery-only smoke detector is cheaper and may suffer fewer false alarms, if that is legal where you live. Otherwise you can try:

1. Buy a new device whenever the problem arises. It will cost about $50 for a cheap import from Asia (less without lithium backup battery) - not bad insurance. Consider paying more (around $100) for a higher-quality device with more sophisticated circuitry that may last longer. You will probably need to ask at an electrical store. Or

2. Take the alarm back where you bought it for replacement. You will need to have the receipt; and you will need to do this every year or so. (Forget this on fleabay, guarantees are worthless there. But big hardware stores don’t seem to know or care that this problem is an inevitable feature of the cheap products. It is certainly a major failure within 10 years.) Or

3. Take the device somewhere that has a compressed air jet, and try to clean it out without damaging the sensor. Consider whether to partly disassemble the alarm for cleaning. Disassembly is not too hard after you work it out, but be careful not to break the plastic tabs. Then use a small brush and vacuum whenever you get false alarms. Manufacturers could make the devices more easily cleaned, but they probably don’t want ‘dumb’ users fiddling about inside. Regulators might not like it either. Also, it may not help. And disassembly will void any guarantee. It is safe with photoelectric alarms, once they are removed from the electricity. Never try it with ionization/radiation alarms. Always test an alarm after cleaning.

After tiring of #2; I tried #3 but it did not help. So I have returned the fault-prone device (Quell 2300LL made-in-China) for refund, and installed a more sophisticated device. Red brand (made-in-Australia) alarms are well regarded and specify high humidity resistance (to 95% RH), but do not advertise built-in ripple resistance or dust compensation. I bought Brooks EIB3106 (made-in-Ireland), though the guarantee is only 5 years. It works great for now - time will tell whether it lasts without false alarms.