Our bedroom air conditioner (AC) emits an odour. We got it serviced but the AC vendor couldn’t rectify the problem. Initially, we thought there may be a dead rodent inside, but that wasn’t the case. The odour gets worse when the AC is switched on. We have resorted to placing incense in the room, but to no avail. Can you suggest a solution?

Sumit Kumar

The smell can be due to dirt within the AC, or it could be picking up the odour from its surroundings. By getting it serviced, you have eliminated the possibilities of dead creatures inside or dirt causing the odour. That leaves us with the surroundings. Mostly, window and split ACs simply recirculate room air, with fresh air coming in only through gaps in windows and below the doors. However, both systems are actually able to take in some air from outside as well. Window ACs take in some air from the rear. Some window ACs also come with a tiny mechanical switch that operates a vent at the rear of the machine. The technology is quite similar to that in a car and can be used to shut the entry of foul air, if required. The split AC, however, takes in air through its (water) drain pipe.

Also, ensure gaps between the machine and the opening it fits into, or over, are properly sealed. Tiny gaps can be neatly covered with a silicone sealant, while larger ones can be first filled with foam strips, cotton fibre, thermocol or another flexible, mouldable insulation. Tape fixed over the gaps would also do the trick.

Sometimes, vendors installing a split AC release its (water) drain pipe over an adjoining bathroom or kitchen drain, without taking precautions to prevent foul air from rising through it and circulating into a room. Whether below or above the floor level, the creation of a simple loop (see illustration) at the discharge end, raising the mouth upwards, can effectively prevent odours and insects from entering the AC.

How can I get rid of the scratching sound a ceiling fan makes at low speed? The sound disappears when it operates at full speed. We’ve oiled the bearings, but that didn’t help.

Feroze Vadiwala

The scratching sound could be due to the wear and tear of its (built-in) bearings. This is easily repaired.

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The sound can also occur when low-capacity, smooth-moving electronic regulators are used. Simply replace these inexpensive “local" mechanisms with ones that have at least four or more pre-defined speeds. Though old, the pre-defined speed technology is an effective solution. If you are using modular switches, the choice of replacements is restricted to the existing manufacturer, as only those will fit the current switch plate design (switches from most brands don’t fit into the switch plate of another).

You should also see if you have sufficient space in the existing plate, as local electronic fan regulators often take only one slot space, while most branded fan regulators require two slots in the switch plate. With the new regulator, you should be rid of the scratching sound even at low speeds—provided the fan bearings haven’t worn out.

My sea-facing apartment on the 11th floor gets a strong breeze that makes the doors slam shut. This has led to the development of big cracks between the door frame and the wall. What should be done?

Sabia Shastri

Try these simple solutions:

Affix a door closer, where possible. It’s not very effective if you have mortise locks—commonly used—on the shutters. Mortise locks, unlike deadbolts, have a lip that you retract by twisting the handle when opening or closing the shutter. It is this lip that stops the shutter from moving back and forth freely. The movement of the door slows when we fix a door closer. However, the lip of a mortise lock prevents the slow-moving shutter from shutting completely. You could either remove this lip (the handle would no longer turn to open or shut the door) and add a deadbolt, or replace it with a different lock and handle mechanism that shuts even at a slow speed.

Fix a wide band of wood panelling on the walls adjoining the door frame. The band should be at least 6-8 inches wide and should cover the affected area completely. The cracks between the frame and the wall would still exist, but won’t be visible if the panelling overlaps the edge of the frame. Polish or paint as desired.

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