Monsoon and your chimney: grease, damp and that stale smell

The north-east monsoon from October to December gives a kitchen chimney three specific problems: rain and debris entering the duct outlet, damp air turning old grease into a sour smell, and moisture from cooking that will not leave a humid kitchen. All three are worse if the unit went into the season already carrying a load of grease.

The single most useful thing you can do is book the deep clean before the rains rather than after. A clean blower and a clear duct handle the season; a greasy one collects water on top of oil and starts smelling within weeks.

The duct outlet does most of the damage

Everything that goes wrong outdoors goes wrong at the wall opening.

• No cowl. Driving rain enters the pipe directly and runs back towards the motor.
• Flap stuck open. Grease or swelling stops the non-return flap seating, so rain, outside air and smell come back in.
• Flap stuck shut. The opposite fault, equally common after a wet spell — the motor runs against a closed door and suction disappears entirely.
• Blocked outlet. Leaves, insects and the nest a bird built during the dry months. A chimney that sounds perfectly normal but moves no air is usually this.
• No outward slope. A duct that runs level or slopes inwards holds water instead of draining it.

Check the outlet from a stable position before the season starts, or ask for it at service time. This is exactly the check people skip.

Why the smell appears

Grease that has settled in the duct and on the blower is a food residue. In dry heat it hardens and mostly stops smelling. In weeks of high humidity it stays soft, absorbs moisture and turns stale. Add a flap that no longer seals and the kitchen gets a faint sour draught whenever the wind is in the wrong direction.

A room freshener does nothing here. The smell is in the duct and on the wheel, and it goes when they are cleaned.

Damp inside the kitchen

Boiling, steaming and pressure cooking put a lot of water into the air. In dry months it disperses; in a Nellore monsoon it condenses on the coolest surfaces it can find — tile grout, the wall behind the hob, cabinet shutters and the underside of the slab. Left through a whole season that shows as dark patches in the corners, swollen cabinet edges and lifting laminate.

Run the chimney through the entire cooking session and for several minutes afterwards. A ducted unit is genuinely removing that moisture from the house; a ductless one is not, so open a window as well.

Before the season: a short list

• Book the deep clean of motor, blower and filters — ₹499 on our rate card.
• Have the duct outlet, cowl and non-return flap checked and cleared.
• Confirm the duct has a slight fall towards the outside.
• Check duct clamps and tape are intact, so grease and water cannot leak into a cabinet.
• Wash filters and dry them completely before refitting.
• On the coastal side — Muthukur, Krishnapatnam, the eastern edge of the city — look for rust at the body edges and fixings, and flag it while the unit is open.

During the season

Keep emptying the oil cup on schedule, because a full cup and damp air together make the mess much worse. Wipe the hood dry rather than leaving it wet after cleaning. If you get a power cut mid-cooking, switch the chimney off at the socket rather than leaving it on to restart by itself when supply returns at an odd voltage.

If water drips from the hood, if the unit trips the MCB, or if you see any spark or smell burning, switch off at the socket or MCB and leave it off. Water inside a motor housing is not something to dry out and hope about.

When to call

Weak suction that clean filters did not fix, a smell that survives a filter wash, water entering the hood, or a flap you cannot see or reach — all of those are technician jobs. The weak-suction booking at ₹499 covers a motor check and duct clearance, which is the right one when the monsoon is the suspect. Any part is charged at MRP and shown to you before it is fitted.