★ Home odour diagnosis · AC rooms
A smell with an on-switch has a source with an on-switch — and that source is the machine
If the smell arrives within seconds of the compressor starting and fades when you switch off, the room is not the source. The unit is.
Start here
A split AC cools by pulling room air across an evaporator coil held below dew point. The coil is wet the entire time it runs. Wet, dark, dusty surfaces grow biofilm.
Condensation
The blower wheel sits downstream of that coil. Whatever grows on the fins gets blown into the room at the moment the fan spins up — which is why the smell is a burst, not a build.
Coil · blower · drain pan
The test takes ninety seconds. Run the unit on fan-only with cooling off. If the smell still appears, it is on the filter or the blower. If it only appears when the compressor runs, it is the wet coil.
The fan-only test
An AC recirculates. It cools the same air over and over and brings in none from outside, so anything the unit emits stays in the room with you.
Cooling is not airing
Once the coil, filter and drain are dealt with, a reed diffuser from ₹749 gives the room a settled background. Not before — fragrance adds, it never subtracts.
Reeds ₹749 · Sukoon ₹1,899
If the smell arrives within seconds of the compressor starting and fades when you switch off, the room is not the source. The unit is.
Start here
A split AC cools by pulling room air across an evaporator coil held below dew point. The coil is wet the entire time it runs. Wet, dark, dusty surfaces grow biofilm.
Condensation
The blower wheel sits downstream of that coil. Whatever grows on the fins gets blown into the room at the moment the fan spins up — which is why the smell is a burst, not a build.
Coil · blower · drain pan
The test takes ninety seconds. Run the unit on fan-only with cooling off. If the smell still appears, it is on the filter or the blower. If it only appears when the compressor runs, it is the wet coil.
The fan-only test
An AC recirculates. It cools the same air over and over and brings in none from outside, so anything the unit emits stays in the room with you.
Cooling is not airing
Once the coil, filter and drain are dealt with, a reed diffuser from ₹749 gives the room a settled background. Not before — fragrance adds, it never subtracts.
Reeds ₹749 · Sukoon ₹1,899
✓ Diagnosis first — if the cause is damp, drainage or a filter, fragrance is not the fix ✓ Reeds from ₹749 for always-on rooms · Sukoon ₹1,899 when you want a switch ✓ Composed by an ISIPCA Versailles-trained perfumer · phthalate-free
Founder Diaries · Why does my home smell like this?
Why it is a burst and not a build: the blower sits downstream of the coil. When it spins up it delivers a concentrated slug of that air in the first few seconds.
The ninety-second test: run fan-only with cooling off. Smell present = filter or blower. Smell only with the compressor running = the wet coil.
Step fourFrom ₹799Lift the front cover of the indoor unit and the mesh filters slide out. In most Indian bedrooms, after a month of use, they hold a grey felt of dust, skin flakes, textile fibres and hair. That mat sits directly in front of a coil that is dripping condensate, so it is not dry — it is humid organic material with air rushing through it many times an hour. Wash them under a tap with a soft brush and mild soap, then dry them completely before refitting. A damp filter put straight back is worse than the dirty one you took out. Once a month during the season is the right rhythm, and fortnightly if you are on a dusty road.
Reeds · always-on roomsFrom ₹749Shop → 
Sukoon · when you want a switch₹1,899Shop → 
Hotel Collection · the scentFrom ₹299Shop →
SOSA products & prices (verified August 2026): Hotel Collection water-based ultrasonic diffuser fragrance 15ml ₹299 · 100ml ₹999 · 300ml ₹1,799 · Pack of 7 (15ml, all fragrances) ₹1,799; refills 100ml from ₹999. Seven scents: The Ritz-Carlton-inspired (white tea · bergamot · cedar), Westin-inspired (white tea · aloe · cedar), 1 Hotels-inspired (cedarwood · vetiver · green leaves), The St. Regis-inspired (amber · violet · woods), Shangri-La-inspired (jasmine · green tea · white tea), Four Seasons-inspired (citrus · floral · sandalwood), W Hotels-inspired (citrus · pepper · amber). Diffusers: Boond 300ml ₹899 · Sukoon 500ml ₹1,899 · Megh 6L ₹3,499. Water-based, phthalate-free, composed to IFRA standards for home diffusion; 3–6 drops per tank. Made in India, Pune. The Hotel Collection scents are SOSA's own interpretations inspired by the world's finest hotels; all hotel names are trademarks of their respective owners and are used only to describe the scent style — SOSA is an independent Indian fragrance house, not affiliated with or endorsed by any hotel brand. Prices and availability subject to change — see the live product pages.
Pay attention to the timing, because the timing is the whole diagnosis. If the smell appears within seconds of the unit starting and thins out after you switch it off, you are not smelling your bedroom. You are smelling the inside of a machine that has just started pushing air at you. Nothing in the room changed. The only thing that changed is that a fan began moving air across a wet metal coil and out through a grille — and it carried whatever is living on that coil into the room with it.
Quick answers — read this first
What is happening: a split AC cools by drawing room air over an evaporator coil kept below the dew point. Condensation forms. The coil stays wet for every hour the unit runs, and wet dusty metal in the dark grows biofilm.Why it is a burst and not a build: the blower sits downstream of the coil. When it spins up it delivers a concentrated slug of that air in the first few seconds.
The ninety-second test: run fan-only with cooling off. Smell present = filter or blower. Smell only with the compressor running = the wet coil.
The short answer
Short answer: Because the smell is coming from inside the air conditioner, not from the room. The evaporator coil runs below dew point and is therefore permanently wet while the unit is on. Dust that gets past the filter sticks to that wet surface and grows a bacterial and fungal film. Switching on the blower blows it into the room. Timing that tight — seconds, not minutes — rules out almost everything else.
What to clean, in order: The washable mesh filters first, because they are two minutes of work and often the whole answer. Then the fins of the evaporator coil. Then the blower wheel, which needs a technician on most split units. Then the drain pan and drain line. Do not fragrance any of this — you would simply be adding a second smell to the first.
Where fragrance fits: After the unit is clean and the room has been aired. A reed diffuser from ₹749 then gives a bedroom a quiet permanent background, or the Sukoon at ₹1,899 gives you something with a switch. Neither one removes a coil smell, and neither should be asked to.
In this guide
Always-on
Reed diffusers · from ₹749
On demand
Sukoon 500ml · ₹1,899
The scent
Hotel Collection · from ₹299
Straight answer
Why does my bedroom smell weird the moment I turn the AC on?
1. Because the smell has the same on-switch as the machine. This is the single most useful observation you can make about a household odour, and most people make it without realising what it tells them. Room smells build slowly and fade slowly. A smell that appears within five or ten seconds of a fan starting, and drops away once the fan stops, is being carried by that fan. It is not the mattress, not the curtains, not the bathroom next door. The air conditioner is the delivery mechanism, and almost always also the source.
2. Because the evaporator coil is permanently wet. Cooling works by holding a coil below the dew point of the air passing over it. Moisture condenses out of that air onto the fins — that is where the water in the drain pipe comes from, and it is the point of the design. But it means the coil is a wet, dark, finely-ribbed metal surface for every hour the unit runs, sitting in a warm room. Fine dust that slips past the filter lands on it and sticks. Wet organic dust on a dark surface grows biofilm. That growth is what you are smelling, and the description people reach for is almost always socks, wet cardboard or old cloth.
3. Because the blower is downstream of the coil. On a split unit the barrel-shaped blower wheel sits behind the coil and throws air out through the louvres. When it starts, the first air out of the grille is air that has been sitting in a damp enclosed box since the unit was last switched off. That is why the smell arrives as a burst and often thins within a few minutes — the concentrated slug clears, and the unit settles into a steadier, weaker version of the same thing.
4. Because the AC is not bringing in any fresh air to dilute it. A split air conditioner recirculates. It takes room air in at the top, cools it, and returns it at the front. It does not exchange air with outside at all. A closed bedroom sits at roughly 0.2–0.5 air changes an hour, so anything the unit emits has nowhere to go and simply concentrates over the evening. The cooling is real; the ventilation is zero.
5. And fragrance is the wrong tool for this specific job. Scent is additive — it puts molecules in and takes none out. Put a diffuser under a smelling vent and the room gets both at once, and a floral over a damp coil is a genuinely unpleasant combination. Clean the filter, clean the coil, clear the drain, air the room. Then a reed diffuser or a Sukoon is worth having, because now it has a neutral room to sit on.
Made in India, composed by an ISIPCA Versailles-trained perfumer — and a portion of every order supports girl-child education through Nanhi Kali.
2. Because the evaporator coil is permanently wet. Cooling works by holding a coil below the dew point of the air passing over it. Moisture condenses out of that air onto the fins — that is where the water in the drain pipe comes from, and it is the point of the design. But it means the coil is a wet, dark, finely-ribbed metal surface for every hour the unit runs, sitting in a warm room. Fine dust that slips past the filter lands on it and sticks. Wet organic dust on a dark surface grows biofilm. That growth is what you are smelling, and the description people reach for is almost always socks, wet cardboard or old cloth.
3. Because the blower is downstream of the coil. On a split unit the barrel-shaped blower wheel sits behind the coil and throws air out through the louvres. When it starts, the first air out of the grille is air that has been sitting in a damp enclosed box since the unit was last switched off. That is why the smell arrives as a burst and often thins within a few minutes — the concentrated slug clears, and the unit settles into a steadier, weaker version of the same thing.
4. Because the AC is not bringing in any fresh air to dilute it. A split air conditioner recirculates. It takes room air in at the top, cools it, and returns it at the front. It does not exchange air with outside at all. A closed bedroom sits at roughly 0.2–0.5 air changes an hour, so anything the unit emits has nowhere to go and simply concentrates over the evening. The cooling is real; the ventilation is zero.
5. And fragrance is the wrong tool for this specific job. Scent is additive — it puts molecules in and takes none out. Put a diffuser under a smelling vent and the room gets both at once, and a floral over a damp coil is a genuinely unpleasant combination. Clean the filter, clean the coil, clear the drain, air the room. Then a reed diffuser or a Sukoon is worth having, because now it has a neutral room to sit on.
Made in India, composed by an ISIPCA Versailles-trained perfumer — and a portion of every order supports girl-child education through Nanhi Kali.
TL;DR: a smell that starts when the AC starts is coming out of the AC. The evaporator coil runs below dew point and stays wet, dust sticks to it, biofilm grows, and the blower delivers it into a room the unit never ventilates. Clean the filter, the coil and the drain — fragrance belongs after that, not instead of it.
After the cause is dealt with
SOSA reed diffusers From ₹749
This belongs at the end of the list, not the start. Once the coil and filter are clean and the room has been aired properly, a SOSA reed diffuser holds a quiet background in a bedroom with no electricity and nothing to switch — 50ml from ₹749 for 6–8 weeks, 130ml from ₹1,249 for 14–18, six fibre reeds included. In a cooled room use four reeds, not six.
Why the timing settles it before you check anything else
Most household odour diagnosis is slow and annoying because smells drift, linger and mix. This one is unusually clean, and you should take the gift. Odour from a fabric reservoir — a mattress, a curtain, a rug — is released by slow diffusion and re-release. It does not have an edge. It is there when you walk in and it is there an hour later, more or less unchanged. Odour from a drain arrives in slugs but on the building's schedule, not yours. Odour that starts within seconds of you pressing a button on a remote is being pushed by the thing that button controls. There is no other mechanism in a bedroom that behaves that way.
That leaves one useful sub-question: is it the wet part or the dry part? Run the unit in fan-only mode, with cooling switched off, for two or three minutes. Fan-only means the blower runs but the compressor does not, so the coil is not being chilled and no new condensation is forming. If the smell still comes out, you are smelling dry deposits — a loaded filter, dust and lint on the blower wheel, or old growth on the fins that is dry but still volatile. If fan-only is clean and the smell only appears once cooling kicks in and the coil goes cold and wet, you are smelling active growth being rewetted. Both need the same eventual work, but knowing which one you have tells you whether a ten-minute filter wash is likely to fix it or whether you need a technician with a coil cleaner and a fin comb.
The three parts of a split AC that actually smell
1
PART ONE · THE FILTER
The two-minute check that is often the whole answer
Step fourFrom ₹799Lift the front cover of the indoor unit and the mesh filters slide out. In most Indian bedrooms, after a month of use, they hold a grey felt of dust, skin flakes, textile fibres and hair. That mat sits directly in front of a coil that is dripping condensate, so it is not dry — it is humid organic material with air rushing through it many times an hour. Wash them under a tap with a soft brush and mild soap, then dry them completely before refitting. A damp filter put straight back is worse than the dirty one you took out. Once a month during the season is the right rhythm, and fortnightly if you are on a dusty road.
The tell: if fan-only mode smells and cooling mode smells about the same, the filter or blower is doing most of it.
2
PART TWO · THE EVAPORATOR COIL
Permanently wet by design
Behind the filter is a block of thin aluminium fins wrapped around copper tubing. During cooling it sits below the dew point of your bedroom air, which is exactly how it dehumidifies — and exactly why it never dries out while running. Fine particulate that slips through the mesh embeds itself between the fins, where it is wet, dark and undisturbed. Biological growth follows, and the classic complaint that follows that is the "dirty sock" smell. You cannot fix this from the front with a spray, whatever the bottle claims, because the growth is deep in the fin pack. This is a service job: a proper jet clean with the drain properly routed, once a season before the heat starts. Between services, one habit helps more than any product — run the unit on fan-only for ten minutes before switching off, which dries the coil instead of leaving it wet all night.
The tell: fan-only is clean, cooling is not. That points at the wet coil rather than dry dust.
3
PART THREE · THE DRAIN PAN AND LINE
Where the water is supposed to go, and often does not
Condensate runs off the coil into a shallow plastic tray and out through a pipe that leaves through the wall. It works by gravity on a small slope and there is no trap and no flush. Over a season, algae and sludge build inside that pipe and it partially blocks. Water then backs up and sits in the pan under the coil — a standing reservoir a few inches from the airflow. That is a different smell from coil biofilm: heavier, more stagnant, and it often gets worse after the unit has been idle for a day. Two things to check without tools. Is water actually dripping steadily out of the outdoor end of the pipe while the unit runs? And is there any drip or damp patch on the wall under the indoor unit? Either answer being wrong sends you to the drain first.
Symptom to cause: reading your own air conditioner
Work down until a row matches the timing you actually observe. Timing is the strongest signal you have here, so be precise about it — seconds versus minutes versus hours genuinely separates the causes.
The diagnosis table
What you notice, what it usually is, and how to be sure
| What you notice | Most likely cause | How to confirm it | What actually fixes it |
|---|---|---|---|
| Smell hits within seconds of switching on, then thins ★ | A slug of stale air from inside the indoor unit being pushed out by the blower | Switch off for an hour, stand a metre from the vent, switch on and breathe the first air out | Wash the filters; run fan-only for ten minutes before every shutdown |
| Present in fan-only mode as well as cooling | Dry deposits — a loaded filter or dust and lint on the blower wheel | Slide the filters out and smell them directly; look at the blower with a torch | Wash filters monthly; get the blower wheel cleaned at the next service |
| Only when cooling runs, never on fan-only | Biofilm on the wet evaporator coil being rewetted | Alternate two minutes fan-only with two minutes cooling and compare | Professional coil clean before the season; dry-run the coil before shutdown |
| Heavier, stagnant note, worse after a day unused | Standing water in the drain pan from a partly blocked condensate line | Check that water drips steadily from the outdoor end of the drain pipe while running | Clear the drain line; make sure it still falls continuously along its run |
| Room smells closed even when the AC smells fine | Recirculation — the unit cools the air but exchanges none of it | Open the room fully for ten minutes and re-enter after thirty | Cross-ventilate morning and night; the AC is not a ventilator |
| Dark speckling on the wall or ceiling around the unit, or an earthy note | Mould growth from a leak or chronic condensation — not an odour problem | Look above and behind the indoor unit and along the drain pipe run with a torch | Find the moisture source, remove the growth, fix the leak. Do not fragrance this. |
| If none of these fit: switch the AC off entirely for a full day and see whether the room still smells wrong. If it does, the unit was never the cause and you are back to the ordinary suspects — bedding, curtains, the bathroom door and how often the room gets aired. | |||
Shop this guide
Where fragrance comes in — after the machine is clean
Reeds · always-on roomsFrom ₹749Shop → Sukoon · when you want a switch₹1,899Shop → Hotel Collection · the scentFrom ₹299Shop →
The SOSA principle
A smell that has an on-switch has a source with an on-switch.
Which is why the first thing to interrogate is not the room, but the machine that has just started moving all of the room's air past a wet metal coil.
What to do, in sequence
First, do the ninety-second test properly, before you clean anything. Leave the unit off for at least an hour so the inside of the casing goes still. Then stand about a metre in front of the vent, switch on in fan-only mode, and breathe the first air that reaches you. Note what you get. Switch to cooling and wait until the compressor is clearly running, then breathe again. You now know whether the problem is dry or wet, which decides whether you can fix it yourself this afternoon or need to book a service. Doing this before you wash the filter is worth it, because once you have cleaned three things at once you will never know which one mattered.
Second, clean in the order of effort. The filters take two minutes and are free: slide out, wash under a tap with a soft brush, dry completely, refit. Then look into the vent with a torch — if the blower wheel has visible grey furring between its blades, add it to the service list. Then check the drain: water should be dripping steadily outside while the unit cools, and there should be no damp patch on the wall beneath the indoor unit. A partly blocked line is a common cause of the heavier stagnant version of this smell, and clearing it is a routine job. Book a proper coil service before the hot season rather than in the middle of it.
Third, change one habit and then add the fragrance layer. The habit: run the unit on fan-only for the last ten minutes before you switch off, so the coil dries instead of sitting wet for eight hours. And open the bedroom fully for ten minutes each morning, because no amount of cooling replaces air exchange. Once the room is genuinely clean, dry and aired, fragrance becomes worth having. In a cooled bedroom the air is cooler and drier and the room is sealed, so you need less, not more: a reed diffuser from ₹749 with four reeds rather than six, kept well out of the vent's airflow, holds a steady background all night. If you would rather have a switch than something always on, the Sukoon at ₹1,899 with three drops of a Hotel Collection scent from ₹299 runs for an hour at bedtime and then stops.
A smell that has an on-switch has a source with an on-switch — and the switch is on your remote.
— Sonal Sahani, SOSA
The order that works
Three of these four steps cost nothing but a Sunday morning, and they are the ones that actually solve the problem. The fourth is the purchase, and it only makes sense once the first three are done.
The order that works
Clean the machine first — the scent is the last line, not the first
| Step | What to do | When | Cost |
|---|---|---|---|
| 1. Remove the source | Wash the AC filters, check the blower wheel, confirm the condensate line is draining freely outside | Before anything else | ₹0 |
| 2. Move the air | Cross-ventilate the bedroom ten minutes morning and night — the AC cools, it never exchanges air | Daily, five to ten minutes | ₹0 |
| 3. Deal with what holds it | Run fan-only for ten minutes before shutdown to dry the coil; wash bedding weekly; book a coil service seasonally | Weekly to monthly | ₹0 |
| 4. Then the always-on layer ★ | A SOSA reed diffuser — a quiet all-night background in a cooled bedroom — four reeds rather than six, away from the vent | 50ml 6-8 weeks · 130ml 14-18 | from ₹749 |
| 5. Or the on-demand layer | Sukoon with a Hotel Collection scent — scent you switch on at bedtime and switch off; three drops in a cooled room is plenty | Run it when you want it | ₹1,899 |
Honest notes before you buy: the order above is not padding, it is the whole method. Home fragrance is an additive layer — it puts pleasant molecules into the air, it does not remove unpleasant ones. Scenting over a live odour source gives you both smells at once, which reads worse than the original problem, and it removes the signal that was telling you something needed attention. Three causes in particular are never a fragrance problem: visible or suspected mould, which is a health issue and needs the moisture source found and the growth removed; a drain or sewer smell, which usually means a dry P-trap or a failed seal and is a plumbing job; and a gas-like or burning smell, which should be treated as an emergency, not an odour. Persistent damp in a wall or ceiling is a building fault and needs a professional. Once the room is genuinely clean and dry, SOSA reed diffusers run oil-based fragrance with no electricity, while the Sukoon (₹1,899) runs the water-based Hotel Collection — the two liquids are not interchangeable. Reed fragrance is composed and made in India, in Pune; both are phthalate-free and composed to IFRA standards for home diffusion, not for skin or ingestion. A portion of every order supports girl-child education through Nanhi Kali.
The on-demand layer
SOSA Sukoon · 500ml ₹1,899
Once the room is clean and dry, the Sukoon at ₹1,899 gives you scent with a switch — run it for an hour before people arrive rather than all day. It takes 3-6 drops of the water-based Hotel Collection (from ₹299) and covers roughly 270-320 sq ft. A reed diffuser is the opposite trade: no switch, no effort, always on.
SS
ISIPCA
Versailles
Versailles
A note from Sonal
The most common thing I hear about air-conditioned bedrooms is some version of "it smells odd but only when the AC is on", usually followed by a question about which diffuser will fix it. Not one of them will, and I would rather say that than take the order. You have already done the hard part of the diagnosis by noticing the timing. Follow it. It leads to a filter, a coil and a drain pipe, all of which are somebody's job and none of which are mine.
There is a specific failure mode I want to warn you off, because I have seen it more than once. Somebody puts a diffuser directly under the vent, reasoning that the airflow will spread the scent. What actually happens is that the fragrance and the coil smell arrive at your face together, permanently linked, and after two weeks you cannot smell that blend anywhere without feeling faintly ill. Fragrance is additive. Put it over a live source and you have made two problems where you had one.
Once the unit is clean, air-conditioned bedrooms are genuinely lovely rooms to scent, and they need a lighter hand than people expect. Cool air slows evaporation from the reeds, but a sealed room lets whatever does evaporate accumulate rather than escape. Four reeds, not six. Something quiet — lavender and chamomile rather than anything citrus-bright at midnight. A portion of every order funds a girl's classroom through Nanhi Kali.
Frequently asked questions
Why does my bedroom smell weird the moment I turn the AC on?
Because the smell is inside the air conditioner and the fan has just started delivering it. The evaporator coil runs below the dew point so it stays wet the whole time the unit cools, dust that gets past the filter sticks to it, and biological growth follows. When the blower spins up it pushes the air that has been sitting in that damp casing straight into the room, which is why it arrives as a burst rather than building slowly.
How do I tell whether it is the filter or the coil?
Run the unit on fan-only mode with cooling switched off for two or three minutes. The blower runs but the coil is not being chilled, so no condensation forms. If the smell is still there, it is dry deposits — a loaded filter or a furred blower wheel. If fan-only is clean and the smell only appears once cooling starts, it is growth on the wet coil, which needs a proper service clean rather than a spray.
Will a reed diffuser fix an AC smell?
No, and no home fragrance from any brand will. Fragrance is additive: it puts pleasant molecules into the air and removes nothing. Over a live coil smell you get both at once, which reads worse than the original. Clean the filter, service the coil, clear the drain and air the room. After that a reed diffuser is genuinely useful for giving the bedroom a consistent character, which is a different job and a real one.
Does running the AC help air out a stuffy bedroom?
No. A split air conditioner recirculates — it draws room air in, cools it, and returns it to the same room. It exchanges no air with outside at all. A closed bedroom sits at roughly 0.2–0.5 air changes an hour whether the AC is running or not, so cooling and airing are separate jobs. Ten minutes with two openings on opposite sides does more than a whole night of cooling.
What should I use in an AC bedroom once the unit is clean?
A reed diffuser from ₹749 if you want something permanent with no electricity and nothing to operate — but use four reeds rather than six, because a sealed cooled room does not flush anything out. Keep it off the vent's airflow path. If you would rather have a switch, the Sukoon at ₹1,899 with three drops of a water-based Hotel Collection scent from ₹299 runs at bedtime and stops. The two liquids are not interchangeable.
After the coil, filter and drain are dealt with
Clean the machine first — then give the room a character
SOSA reed diffusers composed and made in Pune, 50ml from ₹749 for 6–8 weeks or 130ml from ₹1,249 for 14–18, six fibre reeds included and four of them is right for a cooled bedroom. Or the Sukoon at ₹1,899 with a Hotel Collection scent from ₹299 when you want a switch. Neither removes a coil smell — that is what the filter, the service and the drain are for. A portion of every order supports girl-child education through Nanhi Kali.
Shop SOSA reed diffusers → See the Sukoon ₹1,899
Continue the read
More on air-conditioned rooms and smell
- My room smells fine until I switch on the AC — isolating the unit, step by step.
- Why does my split AC sometimes smell musty? — coil, blower, pan and drain line.
- Can a dirty AC filter make a clean bedroom smell bad? — a month of dust becoming a smell.
- Fragrancing an AC bedroom after the fix — why a cool room needs less, not more.
- Brand: the SOSA founder story.
Editorial standards & sources
About this guide: Written by Sonal Sahani, ISIPCA Versailles-trained founder and perfumer at SOSA Home & Body. Odour diagnosis here is general building and household guidance, not a substitute for a plumber, an electrician or a damp specialist where one is needed. Fragrance longevity and coverage figures are SOSA's own for the stated products; the underlying principles — sorption into soft materials, air-change rate and olfactory adaptation — are general.SOSA products & prices (verified August 2026): Hotel Collection water-based ultrasonic diffuser fragrance 15ml ₹299 · 100ml ₹999 · 300ml ₹1,799 · Pack of 7 (15ml, all fragrances) ₹1,799; refills 100ml from ₹999. Seven scents: The Ritz-Carlton-inspired (white tea · bergamot · cedar), Westin-inspired (white tea · aloe · cedar), 1 Hotels-inspired (cedarwood · vetiver · green leaves), The St. Regis-inspired (amber · violet · woods), Shangri-La-inspired (jasmine · green tea · white tea), Four Seasons-inspired (citrus · floral · sandalwood), W Hotels-inspired (citrus · pepper · amber). Diffusers: Boond 300ml ₹899 · Sukoon 500ml ₹1,899 · Megh 6L ₹3,499. Water-based, phthalate-free, composed to IFRA standards for home diffusion; 3–6 drops per tank. Made in India, Pune. The Hotel Collection scents are SOSA's own interpretations inspired by the world's finest hotels; all hotel names are trademarks of their respective owners and are used only to describe the scent style — SOSA is an independent Indian fragrance house, not affiliated with or endorsed by any hotel brand. Prices and availability subject to change — see the live product pages.