If your AC is not cooling after servicing, the problem may be due to incorrect gas charging without a leak test, incomplete deep cleaning, blocked airflow, refrigerant leakage, poor vacuuming, electrical faults, circuit fault or compressor issues. Sometimes, improper servicing cannot find accurate problems or hidden technical faults; as a result, it can reduce cooling performance after servicing your AC. It only requires unskilled or low-cost technicians because they do not know about servicing methods.
Introduction: Many AC users feel disappointed when their units do not cool properly, even after servicing. As a technician, I see this issue in homes, offices, apartments, restaurants, and commercial buildings.
Most customers expect strong cooling performance right after AC servicing. However, servicing alone cannot fix every problem sometimes; hidden issues exist inside the AC’s cooling system, electrical parts, or result from improper installation.
Bangladesh is an extreme heat, high humidity, dust, and unstable voltage provider, and it puts extra pressure on the air conditioning system. If the servicing is incomplete or incorrect, then your AC will still give poor cooling performance.
This article explains the common reasons why an AC is not cooling after servicing. It also covers simple troubleshooting, refrigerant problems, airflow issues, compressor faults, and real HVAC field experience in an easy-to-understand way.
I disclose some important matters or common issues about “Why is My AC Not Cooling after Servicing” from my years of field experience.
What Should Happen After Proper AC Servicing?
A properly serviced AC should normally provide:
- Strong airflow.
- Faster room cooling.
- Reduced compressor load.
- Lower electricity consumption.
- Better humidity control.
- Cleaner indoor air.
Typical Cooling Performance
| Parameter | Normal Value |
| Air outlet temperature | 12°C to 18°C |
| Room cooling reduction | 8°C to 14°C |
| Compressor current | Rated value |
| Airflow performance | Stable |
| Humidity control | Improved |
If these results do not improve after servicing, another technical problem is present in your cooling system. So, need you to be an expert AC technician.
Main Reasons Why AC Is Not Cooling After Servicing
1. Improper Gas refilled
One of the biggest causes behind poor cooling after servicing is incorrect refrigerant (gas) charging by an unskilled technician.
Low Cost technicians refill refrigerant without:
- Pressure testing.
- Vacuuming.
- Weight measurement.
- Superheat checking.
- Sub-cooling analysis.
Problems Caused by Wrong Gas refilled
| Condition | Result |
| Overcharging | High pressure and weak cooling. |
| Undercharging | Low cooling and ice formation. |
| Mixed refrigerant | Compressor stress. |
| Air inside system | High temperature and pressure. |
Refrigeration Principle
The cooling capacity depends on refrigerant mass flow rate.
Q=m×hfgQ = m \times h_{fg}Q=m×hfg
Where:
- Q = Cooling capacity
- m = Refrigerant mass flow
- hfg = Latent heat of vaporization
If your AC refrigerant charge is incorrect, heat absorption becomes unstable.
2. Refrigerant Hidden Leakage Still Exist.
Many unskilled technicians refill the refrigerant without a leak test, and it’s the most common issue in Dhaka.
As a result:
- Cooling improves temporarily.
- Gas leaks again.
- Pressure drops.
- Cooling becomes weak within days or weeks.
Common Leakage Areas
- Flare nut joints.
- Copper piping bends.
- Indoor evaporator coil.
- Condenser coil.
- Service valve.
Real Experience
An AC user lives in Dhanmondi Zigatola, he called me, his general AC, it is not cooling, he has been giving gas and servicing it, it is not working now after servicing and gas refilled, a technician from the general company is coming to work, he is taking money but it is not working after works sometimes, after that I went, I did not find any leak, later I opened the cooling pipe (indoor & outdoor connected), checked the whole pipe, I saw the cooling pipe is leaking, for which I did not find any leak and now he is very happy and getting best cooling service and he gives me extra tips and he is now fixed customer.
3. Poor Indoor Coil Cleaning
Many low-cost or unskilled technicians clean the air filter and outer cover, but ignore deep evaporator coil cleaning with a high-pressure water gun.
When the evaporator remains dirty:
- Heat transfer decreases.
- Airflow becomes weak.
- Cooling performance drops.
- Ice formation may occur.
Airflow Reduction Example
| Coil Condition | Airflow Performance |
| Clean coil | Normal |
| Dirty coil | Reduced significantly |
Dust is a main component of the cooling system, and it’s like insulation and blocks heat absorption.
4. Dirty Outdoor Condenser Coil
The condenser coil releases indoor absorbed heat to the outside, but after servicing your outdoor unit is dust or dirt inside the condenser, then:
- Heat rejection becomes poor.
- Compressor pressure rises.
- Cooling efficiency decreases.
- Electricity usage increases.
These problems are most common in Bangladesh due to dust and pollution.
5. Improper Vacuuming During Servicing
Vacuuming is one of the most important parts of the AC installation and gas refill. Unfortunately, many technicians skip this step for time saving.
Why Vacuuming Is Important
Vacuuming removes:
- Moisture
- Air
- Non-condensable gases
Without proper vacuuming:
- Compressor temperature increases.
- Refrigerant pressure becomes unstable.
- Cooling efficiency drops.
- Ice may form.
ASHRAE Recommendation
ASHRAE recommends proper evacuation and leak testing before refrigerant charging for cooling system efficiency increase and compressor protection high.
6. Weak Airflow after Servicing
After AC servicing, weak airflow can reduce cooling, and it’s very frustrating or disappointing.
Possible Reasons
- Weak blower motor.
- Faulty capacitor.
- PCB issues.
- Blocked evaporator fins.
- Improper fan speed setting.
Weak airflow prevents cold air from spreading properly inside the room.
7. Compressor Problems
A weak compressor cannot circulate refrigerant properly in the cooling system. When you servicing is done, but the cooling has weak airflow, then the compressor efficiency drops.
Common Compressor Faults
- Worn internal valves.
- Low compression ratio.
- Overheating.
- Electrical winding damage.
- Locked rotor condition.
Pressure Difference Formula
ΔP=Pd−Ps\Delta P = P_d – P_sΔP=Pd−Ps
Where:
- Pd = Discharge pressure
- Ps = Suction pressure
Low pressure difference often indicates compressor inefficiency.
8. Low Voltage Supply
Low voltage is a major problem in most areas of Dhaka, Bangladesh.
When voltage becomes low:
- Compressor torque decreases.
- Cooling performance drops.
- Current increases.
- Compressor overheating occurs.
- PCB fault show
Recommended Voltage Range
200V≤V≤240V200V \leq V \leq 240V200V≤V≤240V
I always recommend using a stabilizer in unstable electrical areas.
9. Thermostat or Sensor Fault
Modern inverter AC systems use electronic sensors for temperature control.
Faulty sensors may cause:
- Incorrect room temperature reading.
- Continuous compressor operation.
- Weak cooling.
- Frequent compressor stopping.
Common Faulty Parts
- Room temperature sensor
- Coil thermostat
- PCB board
- Inverter module
10. Incorrect AC Capacity
An undersized AC struggles continuously in large rooms for cover cooling, but he cannot do properly.
Cooling Load Formula
Q=UAΔTQ = U A \Delta TQ=UAΔT
Where:
- Q = Heat load
- U = Heat transfer coefficient
- A = Surface area
- ΔT = Temperature difference
Room Capacity Guide
| Room Size | Recommended AC |
| 100 to 120 sq ft | 1 Ton |
| 142 to 140 sq ft | 1.5 Ton |
| 140 to 160 sq ft | 2 Ton |
If your room size is exceeded than AC capacity, it becomes weak cooling even after servicing.
Energy Consumption Before and After Proper Servicing
A poorly AC serviced is consumes more electricity then becomes more electric bill.
Practical Energy Comparison
| AC Condition | Daily Consumption | Monthly Cost |
| Poor servicing | 12.4 kWh/day | Higher |
| Proper servicing | 8.6 kWh/day | Lower |
Energy Saving Formula
Energy Saving=E1−E2E1×100%\ text{Energy Saving} = \frac{E_1 – E_2}{E_1} \times 100\%Energy Saving=E1E1−E2×100%
I saw that in my practical work experience that proper AC servicing can reduce electricity usage by 15% to 30%.
Why This Problem Is Common in Bangladesh
Bangladesh is the high humid and hot climatic place in the world; for that reason, here is AC smoothly operate difficult for her condition because of
- High humidity
- Heavy dust
- Long operating hours
- Extreme summer temperatures
- Voltage instability
These environmental conditions increase AC maintenance requirements significantly, and its money loses process.
Pros and Cons of Regular AC Servicing
| Pros | Cons |
| Better cooling | Service cost |
| Lower electricity bills | Requires scheduling |
| Longer compressor life | Poor servicing may create problems |
| Better air quality | |
| Lower breakdown risk |
Comparison between proper and poor Servicing
| Feature | Proper Servicing | Poor Servicing |
| Cooling efficiency | High | Weak |
| Refrigerant stability | Stable | Unstable |
| Compressor protection | Better | Poor |
| Electricity usage | Lower | Higher |
| Indoor comfort | Better | Reduced |
Real Field Case Study
One of my customers has complained that his AC is not cooling even after servicing. After that, I reached her office at Gulshan-2, Dhaka (Grammen Uniqlo Ltd), and at first see these symptoms:
Initial Symptoms
- Continuous compressor operation
- Weak airflow
- Warm room temperature
- High electricity bill
My Inspection Findings was:
- Incomplete evaporator cleaning
- Refrigerant undercharge
- No proper vacuuming
- Condenser partially blocked
My Repair Procedure was:
- Deep coil cleaning
- Leak testing
- Vacuuming
- Accurate refrigerant charging
- Current and pressure monitoring
Final Results
| Parameter | Before Repair | After Repair |
| Room temperature | 34°C | 24°C |
| Compressor current | 9.3A | 6.5A |
| Cooling time | 95 minutes | 32 minutes |
This customer reports to me after 3 weeks that his AC is giving better cooling and lower electricity usage over time.
.
FAQs.
Why is my AC not cooling after gas charging?
If your AC is not cooling after servicing, the problem may be due to incorrect gas charging without a leak test, incomplete deep cleaning, blocked airflow, refrigerant leakage, poor vacuuming, electrical faults, circuit fault, or compressor issues.
Can improper servicing damage the compressor?
Yes, wrong refrigerant charging, poor vacuuming, and dirty coils can increase compressor stress and may damage your compressor.
How often should AC servicing be done in Bangladesh?
It depends on your AC condition and usage. Our country’s weather is very rough, so you need to do it every 3 to 6 months.
Does poor servicing increase electricity bills?
Yes. Poor AC servicing increases compressor load or stress, and energy consumption increases automatically.
Why does my AC cool for some time and then stop cooling?
It indicates refrigerant leakage, sensor problems, airflow restriction, or compressor overheating, or any other problems. The cooling system is for the actual findings.
Final Verdict
Finally, I can see that if your AC is not cooling after servicing, the problems involve incorrect gas refilled without a leak test, hidden leakage, inner issues, dirty coils, and compressor inefficiency.
From my practical experience, I say proper servicing means much more than basic cleaning. A complete professional AC service includes leak testing, vacuuming, pressure analysis, airflow inspection, electrical checking, and accurate refrigerant charging. So you need to have professional AC Master deep clean servicing with full inspection for faster cooling, save electricity, improved airflow, and long-term performance.
AIRCONcare is an Authorized AC Service Center in Dhaka, Bangladesh. Here are lots of trained technicians who can provide professional AC servicing and checking to find issues.
Hi, this is Khaled from AIRCONcare. I have been working in multi-brand Air Conditioner Sales and Service for about 18 years. I have many top-most efficient technicians and engineers.