AC Not Cooling? Here’s Why — And How to Fix It
It’s the middle of summer in Dhaka. You switch on your air conditioner, wait a few minutes — and the room stays stuffy and warm. Sound familiar? A non-cooling AC is one of the most reported problems across Dhaka households, from Mohammadpur to Gulshan to Mirpur.
The good news: most causes behind a poorly cooling AC are fixable. Some you can handle yourself; others need a trained technician. In this guide, Reliable AC Service Ltd. breaks down every major reason your AC isn’t cooling, what to check first, and when to call for professional AC repair in Dhaka.
What’s Inside
1. Clogged or Dirty Air Filter
This is the single most common reason an AC underperforms in Dhaka — and also the easiest to fix. Dhaka’s air is thick with dust, pollution, and fine particles. When your air filter gets clogged, airflow through the indoor unit is choked, the evaporator coil can’t absorb heat properly, and the room stays warm no matter how long the AC runs.
Filters in Dhaka homes should ideally be cleaned every 2–4 weeks during heavy use months. If yours hasn’t been touched in two or three months, that’s almost certainly a contributor to poor cooling.
Quick Check: Hold your filter up to a light source. If you can’t see light through it easily, wash it with lukewarm water, let it dry fully, and reinstall. You’ll often feel a difference within minutes.
2. Low Refrigerant (Gas) or a Gas Leak
Refrigerant — often called “AC gas” — is the chemical that your AC uses to absorb heat from indoors and release it outside. If refrigerant is low, the system physically cannot remove enough heat, and you’re left with lukewarm air blowing from the vents.
Unlike a car, an AC doesn’t “use up” gas over time. If levels are low, it means there’s a leak somewhere in the copper piping or at a joint. Simply refilling gas without finding and sealing the leak is a temporary fix at best — the gas will run out again.
Warning: Refrigerant handling requires specialized equipment and is not a DIY job. Improper handling can damage the compressor — the most expensive part of any AC. Always book a certified technician for AC gas refill in Dhaka.
Signs of Low Refrigerant
- AC blows air but it’s barely cool or room temperature
- Ice forming on the indoor unit’s copper pipes
- Hissing or bubbling sound near the unit
- Higher electricity bills with less cooling output
- AC takes very long to bring the room to temperature
3. Dirty Evaporator or Condenser Coil
Your AC has two sets of coils — the evaporator coil inside and the condenser coil in the outdoor unit. Both need to stay clean to transfer heat efficiently. When they’re coated in dust, grime, or even mould (common in Dhaka’s humidity), heat exchange drops significantly.
A dirty condenser coil is especially common in Dhaka because outdoor units are exposed to road dust, exhaust fumes, and seasonal debris. When the condenser can’t release heat to the outside air, the whole system struggles to keep up.
Annual professional AC deep cleaning in Dhaka is the most effective way to prevent coil buildup. A proper chemical wash can restore cooling efficiency by 20–30% in many cases.
4. Wrong AC Size for the Room
An undersized AC will run non-stop without ever reaching your set temperature. This is a fundamental mismatch that no amount of cleaning or servicing can fix — the unit simply doesn’t have the capacity to cool that volume of air.
Here’s a rough guide for Dhaka’s climate:
| Room Size | Recommended AC Capacity | Typical Usage |
|---|---|---|
| Up to 120 sq ft | 1 ton (12,000 BTU) | Small bedroom |
| 120–180 sq ft | 1.5 ton (18,000 BTU) | Standard bedroom / office |
| 180–280 sq ft | 2 ton (24,000 BTU) | Large bedroom / living room |
| 280–400 sq ft | 2.5–3 ton | Open-plan living area |
Note: If your room has large windows, high ceilings, or faces direct sunlight for most of the day — as many Dhaka apartments do — go one size up.
5. Thermostat or Remote Control Issues
Before assuming a mechanical failure, always check your settings. It sounds obvious, but incorrect thermostat settings are behind many “AC not cooling” complaints. Common culprits include:
Fan Mode Only
If the AC is set to “Fan” instead of “Cool,” it just circulates air without activating the compressor. No cooling happens.
Temperature Set Too High
If your set temperature is 28°C and the room is already 27°C, the AC won’t cool further. Try setting it to 24–25°C.
Dead Remote Batteries
Weak remote batteries can cause intermittent or incorrect signals to the AC, leading to unexpected mode changes.
6. Blocked or Poorly Ventilated Outdoor Unit
The outdoor condenser unit needs clear airflow to expel heat. When it’s crammed into a narrow balcony corner, surrounded by debris, or has its vents partially blocked, it overheats and the entire system’s cooling efficiency drops.
In dense Dhaka residential areas, outdoor units are sometimes boxed in by grilles, laundry, or construction material. Check that there’s at least 50cm of clearance on all sides of the outdoor unit and that the area directly in front of the fan is unobstructed.
7. Faulty or Failing Compressor
The compressor is the heart of your AC — it pressurises the refrigerant and drives the entire cooling cycle. When a compressor starts failing, cooling output drops significantly, and eventually the unit stops cooling altogether.
Signs of a failing compressor include unusual noises (clanking, grinding), the outdoor unit starting and stopping frequently, and the AC cooling intermittently. Compressor replacement is expensive — sometimes it makes more financial sense to replace the unit entirely, especially if the AC is over 8–10 years old.
A trained technician from Reliable AC Service Ltd. can accurately diagnose compressor health using pressure gauges and electrical testing — never assume a compressor has failed without proper diagnosis, as the symptoms can overlap with other fixable issues.
8. Electrical Faults — Capacitors, PCB, and Wiring
Modern ACs are packed with electronics. Start capacitors, run capacitors, PCB control boards, and wiring can all degrade over time — especially given Dhaka’s voltage fluctuations. A failed capacitor is actually quite common and relatively inexpensive to fix, but it will completely stop the compressor or fan motor from starting.
If your AC turns on (you can hear it trying) but the compressor doesn’t engage, or if the outdoor fan isn’t spinning, a capacitor fault is a likely cause. Always have electrical faults diagnosed by a qualified technician.
9. What You Can Check Yourself Before Calling a Technician
Before booking a service call, run through this checklist. These simple steps resolve the problem in about 30% of cases:
Check the AC Mode and Temperature Setting
Make sure it’s set to COOL mode, not Fan or Dry. Set temperature to at least 3–4°C below current room temperature.
Replace the Remote Batteries
Use fresh AA batteries. Test by pointing the remote at a phone camera — you should see the IR LED flash on screen.
Inspect and Clean the Air Filter
Slide out the filter (usually behind the front panel), rinse under water, dry completely, reinstall.
Check the Outdoor Unit
Is it on? Is the fan spinning? Is there debris blocking the vents? Clear any obstruction safely.
Reset the AC
Turn off the AC at the breaker for 5 minutes, then restart. This clears minor control board errors.
Check for Ice on Pipes
If the copper pipes near the indoor unit are frosted or iced over, turn the AC off and run it on Fan Only for 30 minutes to defrost before calling a technician.
If none of the above resolve the issue, the problem is internal and requires professional diagnosis. Attempting to disassemble coils, handle refrigerant, or open the compressor housing without proper training can cause serious injury and void your warranty.
Quick-Reference: Problem, Cause & Fix
| Symptom | Likely Cause | Fix Type |
|---|---|---|
| Blows warm air | Low gas, dirty coil, wrong mode | Pro Service |
| Weak airflow | Clogged filter, blocked vents | DIY / Pro |
| Ice on pipes | Low refrigerant, dirty filter | Pro Service |
| AC won’t start | Capacitor fault, electrical issue | Pro Service |
| Runs but room stays hot | Wrong size AC, blocked outdoor unit | Check / Upgrade |
| Intermittent cooling | Failing compressor, PCB fault | Pro Service |
Still Not Cooling? We’ll Come to You.
Reliable AC Service Ltd. provides same-day AC repair across all Dhaka areas — from Mohammadpur to Uttara. Available every day, 8AM–12AM.
Frequently Asked Questions
The most common reasons are a dirty air filter, low refrigerant gas, a dirty evaporator coil, or a blocked outdoor unit. Start by checking your filter and the AC mode setting. If those are fine, contact a certified technician to check refrigerant levels and coil condition.
Signs include warm air from the vents despite the AC running, ice forming on the indoor copper pipes, a hissing sound near the unit, and unusually high electricity bills. Only a technician with pressure gauges can confirm gas levels accurately.
No. Refrigerant handling requires certified equipment and training. Incorrect handling can damage the compressor, cause personal injury, and is illegal without proper certification. Always use a licensed technician for AC gas refill in Dhaka.
In Dhaka’s dusty environment, clean your filter every 2–4 weeks during peak use months (March–October). If you use the AC year-round, monthly cleaning is ideal. An annual professional deep-clean is also recommended.
Costs vary by issue: a basic cleaning service starts from around ৳500–৳1,000; gas refill runs ৳1,500–৳3,500 depending on gas type; capacitor replacement is typically ৳500–৳800; and compressor work can range from ৳5,000 upward. Contact Reliable AC Service Ltd. on 01824283141 for a specific quote.
