AC Not Cooling in Dhaka? 7 Real Causes & How to Fix Each One
Dhaka’s heat and humidity push air conditioners hard from March through October. When an AC runs but fails to cool, there are exactly seven things that account for roughly 95% of cases. This guide covers each one — what causes it, what it looks like, and whether you can handle it yourself or need a certified technician at your door.
1. Clogged or Dirty Air Filter
Blocked Airflow from a Dirty Filter
Dhaka’s air carries more dust and particulate matter than most cities. AC filters in this city need cleaning every 2–3 weeks during peak summer — not every 3 months like manufacturers suggest for cleaner climates.
When a filter chokes up, the indoor unit cannot pull in enough warm air from your room. The evaporator coil then drops below freezing and sometimes ices over entirely. The result: your AC runs nonstop but barely cools anything.
Signs: Weak airflow from vents, ice visible on the indoor unit pipe, musty smell when AC runs.
✓ DIY Fix 15 Minutes No CostTurn the AC off and let ice melt
If the coil is frozen, run fan-only mode for 30 minutes before opening anything.
Remove and rinse the filter
Use running water — no soap needed. Let it dry fully before reinserting.
Reinsert and test
Run the AC on cool mode for 15 minutes. Airflow should feel noticeably stronger.
2. Low Refrigerant Gas (Gas Leak)
Refrigerant Below Proper Level
Refrigerant (commonly R22 or R410A in Bangladesh) is the chemical that actually absorbs heat from your room. When it leaks — usually through a pinhole in the copper pipe or a loose fitting — the AC loses its ability to cool no matter how long it runs.
Refrigerant doesn’t “run out” normally. If yours is low, there is a leak somewhere. Just refilling gas without fixing the leak is a waste of money — it will leak out again within weeks.
Signs: AC runs but barely reduces temperature, hissing sound near the outdoor unit, ice forming on the copper pipe leading to the outdoor unit, electricity bill increasing without explanation.
⚠ Professional Only Leak Test Required FirstWe always do a leak test before any gas refill. If a competitor quotes gas refill without mentioning leak detection, ask why. Skipping the leak test means the same problem returns in 4–6 weeks.
Our AC gas refill service in Dhaka includes a full pressure test, leak location, pipe repair if needed, and then a proper gas recharge to manufacturer spec.
3. Dirty Evaporator or Condenser Coils
Heat Transfer Blocked by Grime
The evaporator coil (indoor unit) and condenser coil (outdoor unit) both need clean surfaces to transfer heat efficiently. In Dhaka’s dusty, humid environment, these coils accumulate a thick layer of grime within a single season.
A dirty evaporator coil cannot absorb heat from your room. A dirty condenser coil cannot release that heat outside. Either way, cooling drops dramatically — sometimes by 40–50%.
Signs: AC cooling feels weak despite normal airflow, outdoor unit feels excessively hot to the hand, electricity consumption visibly higher than same period last year.
⚠ Professional Recommended Chemical Wash AdvisedA proper AC cleaning in Dhaka involves a chemical wash of both coils — not just a rinse — to dissolve biofilm and mineral buildup that water alone cannot remove. Most homeowners notice a 15–20% drop in electricity bills after a full coil clean.
4. Faulty or Failing Compressor
The Heart of the AC Is Struggling
The compressor is the most critical — and most expensive — component in any AC system. It pumps refrigerant through the system. When it weakens or fails, cooling drops sharply or stops entirely.
Compressors fail for several reasons: running with low refrigerant for too long (causes overheating), voltage fluctuations (very common in Dhaka), age-related wear, or dirty condenser coils forcing it to overwork.
Signs: Outdoor unit starts then quickly shuts off, clicking sounds from outside, circuit breaker trips when AC is turned on, AC runs but produces zero cooling.
⚠ Professional Only Expensive if ReplacedDon’t delay a compressor diagnosis. Running an AC with a struggling compressor makes the problem worse and far more expensive. An early diagnosis at R. K. Refrigeration Works Ltd. can often save the compressor with a capacitor swap or minor repair — versus a full replacement costing 10× more.
See our detailed guide on AC compressor repair in Dhaka for what to expect from the diagnosis and repair process.
5. Thermostat or PCB Control Board Issue
Wrong Signals, Wrong Temperature
Modern split ACs use a PCB (printed circuit board) to manage everything — compressor cycling, temperature sensing, fan speed, defrost mode. When this board develops a fault, the AC may appear to run normally while the compressor never actually activates.
Thermostats can also give false readings, causing the system to think the room is already cool when it isn’t.
Signs: Remote control works but nothing changes, AC turns on then immediately enters standby, temperature display shows wrong reading, intermittent cooling that comes and goes randomly.
⚠ Professional Only Diagnosis Required6. Blocked or Leaking Air Ducts
Cool Air Escaping Before It Reaches You
This applies to ducted or cassette AC systems in offices, commercial spaces, and larger apartments in Dhaka. Duct leaks bleed cool air into walls or ceiling cavities. Even 10–15% duct leakage cuts the effective cooling you feel by a significant amount.
Signs: Some rooms cool fine while others stay warm, visible gaps or disconnections in visible duct sections, musty smell from vents.
⚠ Professional Inspection Sealing or Cleaning NeededOur duct cleaning service in Dhaka and HVAC repair service covers full duct inspection, sealing, and cleaning for commercial and residential ducted systems.
7. Undersized AC for the Room
The AC Simply Isn’t Big Enough
A 1-ton AC installed in a 200 sq ft room will never cool it properly on a 38°C Dhaka afternoon — especially if the room has poor insulation, large west-facing windows, or multiple heat sources. This isn’t a repair issue; it’s a sizing issue.
Signs: AC runs continuously but temperature never drops below 26°C, problem is worse on hotter afternoons, cooling is acceptable at night but not during the day.
Capacity Upgrade Needed Insulation Can HelpQuick Diagnosis: Which Cause Fits Your Situation?
| Symptom You Notice | Most Likely Cause | DIY or Pro? | Urgency |
|---|---|---|---|
| Weak airflow, musty smell | Dirty filter / frozen coil | ✓ DIY | Low |
| Hissing sound, ice on pipe | Refrigerant gas leak | Pro Required | High |
| High electricity bill, weak cool | Dirty coils | Pro Recommended | Medium |
| Outdoor unit clicking, tripping breaker | Compressor fault | Pro Required | High |
| Runs but temp never drops | PCB / thermostat issue | Pro Required | Medium |
| Some rooms cool, others don’t | Duct leak | Pro Inspection | Medium |
| Never cools well, any weather | Undersized unit | Consult & Upgrade | Low |
How to Prevent Cooling Problems in Dhaka’s Climate
Dhaka’s combination of heat, humidity, and dust is uniquely hard on air conditioners. Here is what our technicians at R. K. Refrigeration Works Ltd. recommend to keep your AC cooling efficiently year-round:
- Clean the filter every 2–3 weeks during summer (April–September), not every 3 months.
- Schedule a professional clean once a year — ideally in March before summer starts — covering both coils and the drainage system.
- Use a voltage stabilizer to protect the compressor and PCB from Dhaka’s frequent voltage fluctuations.
- Keep the outdoor unit clear — ensure at least 30cm clearance around it for proper heat dissipation.
- Set temperature to 24–26°C rather than 16°C. Lower settings don’t cool faster; they just run the compressor harder and shorten its life.
- Have a professional check refrigerant pressure annually — a slow leak caught early costs a fraction of a compressor replacement.
Thinking about a deeper clean? Our AC cleaning service in Dhaka covers everything from filter wash to full chemical coil treatment. For a complete tune-up, explore our full range of AC repair and maintenance services.
Is Your AC Not Cooling Right Now?
R. K. Refrigeration Works Ltd. provides same-day AC repair across all Dhaka areas — every day from 8AM to 12AM. Call or WhatsApp for a free over-the-phone assessment.
📞 Call 01859977692 View AC Repair Service →Frequently Asked Questions
The most common reasons an AC runs but doesn’t cool in Dhaka are: a clogged air filter restricting airflow, low refrigerant gas due to a leak, dirty evaporator or condenser coils, a faulty compressor, or a thermostat/PCB board issue. In Dhaka’s dusty climate, a dirty filter is the first thing to check — it’s free to fix and takes 15 minutes. If cleaning the filter doesn’t help, call a professional to check refrigerant levels and coil condition.
In Dhaka’s climate, a professional AC service at least once per year is the minimum — ideally in March before summer begins. Clean the filter yourself every 2–3 weeks during summer months. If you run your AC heavily (8+ hours daily), consider a second professional service in October after monsoon season, as humidity causes mold and grime buildup inside the unit.
AC gas refill cost in Dhaka typically ranges from ৳1,500 to ৳3,500 depending on the gas type (R22, R32, or R410A) and the AC’s tonnage. However, the gas refill cost alone doesn’t include leak detection and repair. At R. K. Refrigeration Works Ltd., we always do a leak check first — refilling without fixing the leak means the gas escapes again within weeks and you pay twice. Call 01859977692 for a precise quote based on your AC model.
The only safe DIY fix is cleaning the air filter. Anything beyond that — refrigerant handling, coil chemical washing, compressor diagnosis, PCB repair — requires trained technicians with proper tools. Refrigerant gases (especially older R22) are classified as hazardous materials, and mishandling them is dangerous. Electrical components inside an AC unit carry high-voltage capacitors that can cause serious injury even after the unit is unplugged.
Yes. R. K. Refrigeration Works Ltd. offers same-day AC repair service across all Dhaka city areas, every day from 8AM to 12AM. Call 01859977692 to book. Service areas include Mohammadpur, Uttara, Mirpur, Dhanmondi, Gulshan, Banasree, Badda, Basundhara, Khilgaon, Pallabi, Baridhara, Banani, Mohakhali, Rampura, and surrounding neighbourhoods.
