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Living Room | Smoke and air quality must never share a rule

One saves lives and can carry no conditions or delay. The other is about comfort and can be tuned freely.
February 24, 2026 by
Living Room | Smoke and air quality must never share a rule
渥屋科技股份有限公司, 系統管理者
Living

SMART HOME BUTLER · LIVING ROOM

Smoke and air quality must never share a rule

One of them saves lives and can carry no conditions, no delay, and no switching off because it woke you. The other is about comfort and can be tuned freely.

2
independent rule sets
0
conditions on the smoke rule
3
air quality levels, all adjustable

Combining them is the most common mistake

Once there is an air quality sensor in the living room, the natural thought is that it also detects smoke, so why not handle both together. Natural, and dangerous.

Because you will absolutely tune the air quality rule. Restrict the hours because it is noisy at night, add conditions because of false alarms, switch it off for a while because it is irritating. Every one of those is reasonable — but if smoke is bundled in, every one of them also weakens your fire alarm.

The correct approach is two entirely separate rules. Tune the air quality one however you like, and never touch a character of the smoke one.

Smoke safety class detected 1 second no levels Siren + every light to full + top-priority alert + extraction on No active hours, no conditions, not suppressed by do-not-disturb Air quality comfort class level one level two level three purifier on low purifier high + suggest a window full ventilation + alerts The top track has no middle state — one trigger and it is at maximum. The lower track escalates, and you can tune it They are entirely separate, so editing the lower one cannot touch the upper one
One sensor set, two logics. The difference is not technical — it is which one you can afford to get wrong.

How the two rules differ

The smoke ruleThe air quality rule
Guards againstFire, and livesLong-term health and comfort
Response timeSeconds, no bufferMinutes, there is time to observe
LevelsNone — one trigger, maximumThree, escalating
Active hoursAlways, cannot be limitedCan be limited, e.g. no night alerts
Extra conditionsNone permitted at allAdd whatever you like
Alert priorityHighest, bypasses do-not-disturbNormal
Can it be switched off?NoYes
That fifth row is the single most important sentence here. Put no conditions on the smoke rule. Not "only when someone is home", not "only during the day", not "unless we are cooking". Every condition is one more reason it might stay silent at the moment it matters.

What the three air quality levels do

  1. Level one

    Handled quietly

    PM2.5 past 35 or a slight TVOC rise. The purifier starts on low and you are not told. Most of the time somebody is cooking and you do not need to know.

  2. Level two

    It speaks up

    PM2.5 past 75 or CO₂ past 1200. The purifier goes to high and you get a notification suggesting a window. This is the first level that interrupts you.

  3. Level three

    Everything on

    PM2.5 past 150. All ventilation to maximum with repeated alerts. Indoors this figure is rare, and it usually means there is a definite source.

  4. Back to normal

    Standing down

    Levels only release below 25, well clear of where they engaged, so the machines are not constantly cycling.

Level one staying silent is deliberate. A notification every time somebody fries something and you will switch the whole thing off within a week. Letting the system handle small things quietly and speak only when it genuinely needs you is what keeps the setup alive.

Four things it takes care of

Early fire warning

What kills in most domestic fires is smoke rather than flame. A few minutes of warning makes an enormous difference.

You will not disable it

Because the smoke rule never nuisance-alarms, you never acquire a reason to switch it off. That is the most practical benefit of separating the two.

Steadily better air

Small events are dealt with without your knowledge. Over time the average indoor air quality rises noticeably.

Quiet

Only level two and above notify. Your phone is not buzzing all day, which means you look when it finally does.

Different homes, different air thresholds

Your situationLevel 1Level 2Level 3Notes
Typical home3575150The general case
Open-plan kitchen4590170Cooking smoke reaches the living room; relax them to avoid constant triggering
Asthma or allergies2550100Shift the whole set down and step in earlier
Infants at home2555110Developing lungs justify being more active
Someone smokes3570140Level two must reliably trigger ventilation, since that is the main source
Whatever you change, do not touch the smoke rule. This table applies only to the three air quality levels.

What you need to have

What it doesCategory in the systemEssential?
Detect smokebinary_sensorYes
Measure air qualitysensorYes
Receive alertsnotify (phone app)Yes
Sound an alarmsiren or switchStrongly advised
Purifier and extractionfan or switchRecommended
Smoke detection needs a dedicated sensor. An air quality sensor measures particle concentration; it will show that cooking smoke has thickened, but it is not a certified smoke detector. The sensing principle and the reliability are different. Do not economise here, and do not substitute one for the other.

How the whole thing works

Smoke detector separate, dedicated binary_sensor _trigger_things Siren + all lights + top alert no conditions, no time limits Air sensor PM2.5 · CO₂ · TVOC greenhouse blueprint three, one per level Level one purifier, silently Levels two and three ventilate, alert
The two paths never meet. The point of this diagram is the connection that is not drawn.

Use the ready-made blueprints

The hub ships with 22 tested automation blueprints — think of one as a fill-in-the-blanks form. Smoke uses binary_sensor_trigger_things; the three air quality levels use greenhouse.

FieldSmoke ruleThree air rules
WatchesThe smoke detectorPM2.5 and CO₂
Triggers onAny detection35 / 75 / 150
ActionsSiren, all lights, alertPurifier, ventilation, alerts
Active hoursAlways, cannot be setNight alerts can be suppressed
Alert priorityHighestLevel one does not notify

Just say the word

You do not have to fill in any of those four rules by hand. The WOOWTECH hub ships with HA-MCP, which lets AI connect straight into your system, build the rules, and then go back and check for itself that each one really fires before it reports back.

YouIf the living room smoke detector goes off, sound the alarm, turn every light on and send me the highest priority alert. Handle air quality in three levels, and do not bother me at level one.
pi agentBoth sensors found. The smoke rule is built as a standalone with no time limits and no conditions, at top notification priority. The three air quality levels are three separate rules, and level one only runs the purifier without notifying. The two sets are fully independent, so tuning air quality later cannot affect smoke. I ran all four once just now and each fired correctly.
YouWill cooking set it off constantly?
pi agentAir quality level one might, but it does not notify so it will not bother you. The smoke unit is a dedicated detector and is much less sensitive to cooking smoke, so normal frying should not trigger it. If it genuinely false-alarms, the fix is to move the detector, not to change the rule.

Prompts you can copy straight across

Every block below can be copied whole with the button on the right. Pick the one closest to what you want — you do not need all five.

The simplest versionuse this if you just want it running
Split living room smoke detection and air quality into two
completely separate rules for me. Never merge them into one.
On any smoke detection, sound the alarm, put every living room
light on and send me the highest priority alert — and put no
hours and no conditions on that rule at all.
For air quality, keep it simple to start with: run the purifier
when PM2.5 gets high. Find the devices yourself, and if one is
missing say so rather than substituting the air quality sensor
for a smoke detector.
The full versionfour rules, thresholds and alerts in one go
Build me four living room rules: one for smoke, three for air
quality. The two sets must be completely independent and must
never be merged.
The smoke rule: on any detection, at the same moment sound the
siren, take every living room light to full brightness, put all
extraction on, and alert me at the highest priority so it gets
through do-not-disturb. That rule may have no active hours and no
extra conditions — no "only when home", no "daytime only", not one.
The three air rules: PM2.5 above 35 runs the purifier low and does
not notify me; above 75 takes the purifier high and messages me to
open a window; above 150 puts all ventilation at maximum with
repeated alerts. All three release only below 25. Levels two and
three may stay quiet overnight; level one never notifies anyway.
Send everything as a phone notification, never as spoken audio,
and use the ready-made blueprints on the hub rather than your own.
When it is built, test it yourself, confirm it really fires, then
tell me which devices you used and how many conditions the smoke
rule ended up with.
Tuned to your homefor an open-plan kitchen
Our kitchen is open to the living room, so cooking smoke drifts
straight in. Loosen the air thresholds across the board: level one
to 45, level two to 90, level three to 170.
The level two window reminder will fire all through dinner, so in
that stretch just ventilate and do not message me.
Leave the smoke rule completely alone — same trigger, same absence
of conditions, same lack of active hours.
Also check where the smoke detector is mounted, and tell me if it
sits too close to the hob. That would be a reason to move it, not
a reason to change the rule.
Changing it lateradjust a threshold in one sentence
Air quality level one is too sensitive — the purifier runs the
whole time I am cooking. Move it from 35 to 45, and move level two
to 90 with it. Keep the release point at 25 as it is.
Do not touch a single thing on the smoke rule, and once you are
done confirm to me that it still carries no conditions at all.
Pausing part of itstop the right rules, never the smoke one
Renovation starts next week and there will be dust in the air all
day, so those three air quality rules would just nag at me
non-stop. Put all three on hold for now, all three of them, not
only the two that alert me.
Leave the smoke rule running exactly as it stands. With builders
in the house I want that one more than ever.
Afterwards, tell me which rules you paused and confirm the smoke
one is still live. And hold on to this for me: the day I say the
work is finished, remind me to switch those three back on.
One caution: the HA-MCP connection URL is the key to your home. Do not post it publicly, and do not give it to services you do not trust.

Common questions

Where does the smoke detector go?
Centre of the ceiling, at least thirty centimetres from any wall. Smoke collects at ceiling level, so wall or corner mounting costs several seconds. Keep it away from air conditioning outlets and doorways, where airflow disperses smoke. In a kitchen, mount it at the edge of the room rather than above the hob.
Will cooking cause constant false alarms?
A dedicated detector is far less sensitive to cooking smoke than an air quality sensor, and normal cooking usually will not trigger it. If it genuinely does, the correct fix is moving the detector further away — never adjusting the rule or disabling it.
Could I use only the air quality sensor?
Not advisable. It measures particle concentration and will tell you cooking smoke has thickened, but it was not designed to detect fire and differs in both sensing principle and reliability. This is not the place to economise.
An alarm at 3am would wake the whole building
That is precisely its job. Restricting the hours to avoid disturbance means abandoning exactly the hours when it matters most — most fatal domestic fires happen at night. The thing to address is the cause of any false alarm, not the volume of the alarm.
How often do batteries need changing?
Around a year for most units. Set up a low-battery notification as well, otherwise a flat detector goes unnoticed. Add an "offline for more than a day" rule at the same time; together they make the protection complete.
Do I have to rebuild to change an air threshold?
No. Just say "level one is too sensitive, make it 45" and the assistant will find that rule and edit it. The smoke rule is untouched.
two systems

A month from now

You barely notice the air quality side working, because it deals with the small things by itself.

And the smoke rule — you hope it never sounds. But you will know it is there, with nothing standing in its way.

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