First month after aircon installation checklist (Singapore)

On handover day, the installer checks that the unit runs, cools to the set temperature, and does not drip. These checks take minutes per unit. They do not reveal how the system behaves through a full night of use, or how it performs when two or three rooms run at the same time.

The first month closes that gap. It reveals whether one zone operates slower than others, whether a pipe joint makes noise when the unit reaches full capacity, or whether the drain line routes correctly under all operating conditions. These patterns only surface with repeated daily use.

Raising an issue in month one is also the most reliable path to a resolution. The installer still has full context on the job. The workmanship warranty is active. Any adjustment is rapid to make and straightforward to agree on. Waiting until a problem becomes obvious later often means a more drawn-out process.

Record how long each room takes to reach comfort at your usual setpoint. A room that operates much longer than others of the same size may have a setup issue — incorrect pipe sizing, low gas charge from the install, or a fan speed that was configured too low during commissioning.

Also confirm whether each unit maintains its set temperature once it reaches it. A unit that reaches comfort and then climbs back up before the next cycle may have a sensor issue or a gas charge that is slightly below spec. This pattern is easier to identify during the first month than after the system has been in daily use for several months.

Compare room-to-room cooldown across the same period of the day. Differences that follow outdoor conditions — the east-facing room always cools faster in the evening than the west-facing one — are normal. Differences that do not follow any recognizable pattern are worth recording.

Some noise is normal in new units. A brief click when the compressor starts, a soft hum from the fan, and a low draining sound when the unit cycles off are all part of normal operation. These sounds settle over the first few weeks as the system beds in.

Noise that gets louder over time is a different signal. A vibration that grows, a rattle that starts after a week of use, or a knocking sound from the outdoor unit that was not present in the first few days all require a closer inspection.

Record the type of sound, which unit it comes from, and when it occurs — during startup, at full capacity, or when cycling down. This specific detail helps the installer trace the cause more rapidly than a general report of unusual noise.

Moisture around the indoor unit or wet marks below the drain pipe outlet are the main signs to watch for. In Singapore's climate, a new unit that is running long daily sessions will push a fair amount of water through the drain line. That line needs to be clear and correctly angled from day one.

A drip from the indoor unit that appears after a long operating session, or damp marks below the unit on the wall, both indicate a drain issue. These are not always visible on handover day because the unit has not operated long enough. They tend to surface in the second or third week of daily use.

If you observe moisture, record the timing and how frequently it occurs before contacting the installer. A pattern of dripping after extended operating sessions is different from a one-off drip on the first day. The pattern reveals whether the drain angle is misaligned or whether the drain pan is the issue.

Use room-by-room notes rather than a general complaint. A report that says one bedroom unit cools slowly in the evening and the other bedroom is fine gives the installer a clear starting point. A report that the system does not cool well is harder to act on.

Include the setpoint you were using, the time of day, and whether the outdoor unit was also running other rooms at the same time. These details help the installer decide whether the issue is a unit fault, a gas level problem, or a normal load-sharing pattern.

Photos or short clips of unusual noise or moisture signs are useful. A ten-second clip of a vibrating pipe joint or a damp mark below the drain outlet removes any back-and-forth about what you observed.

Keep the install quote, handover checklist, warranty terms, and any service notes from the installer in one place. If the installer provided photos of the pipe routing or drainage setup on handover day, retain those too.

Add your month-one notes to the same file as you go. A record that shows the install date, handover outcome, and weekly observations through month one is the most reliable way to support any follow-up discussion.

At the end of month one, review whether any pattern repeated across more than one week. A one-off observation is usually not a concern. A pattern that appeared in week two, week three, and week four is a reason to contact the installer and request a targeted check.