When an air conditioner is running but not cooling a room properly, the problem can be caused by several different components. A customer may hear the indoor unit operating, see the fan blowing air, and assume that the air conditioner is working normally. However, if the air coming from the unit is not sufficiently cold, there may be a fault within the refrigeration system, electrical controls, airflow system, compressor, condenser, evaporator or installation.

Air conditioning repair in Nairobi covers many types of equipment, including residential split air conditioners, portable AC units, commercial air conditioners, inverter AC systems, cassette units, ceiling-mounted systems and larger industrial cooling equipment.

A proper diagnosis is important because an air conditioner that is not cooling does not automatically need refrigerant.

The problem could instead be caused by a dirty filter, blocked condenser, failed fan motor, faulty temperature sensor, compressor problem, refrigerant leak, electrical fault, control-board failure or incorrect installation.

AIR CONDITIONER RUNNING BUT NOT COOLING

One of the most common customer complaints is:

“My AC is running, but the room is still hot.”

The first step is to establish what the air conditioner is actually doing.

The technician should determine:

Is the indoor fan running?
Is the outdoor unit running?
Is the compressor running?
Is the condenser fan running?
Is the evaporator getting cold?
Is there ice formation?
Is the airflow strong or weak?
Is the air conditioner displaying an error code?
Is the refrigerant circuit operating correctly?
Is the room receiving sufficient airflow?

These observations help narrow down the fault.

CHECK THE AC MODE

Before opening the appliance, check the operating mode.

Many air conditioners have several modes, including:

Cool
Dry
Fan
Auto
Sleep
Heat
Turbo

If the customer accidentally selects Fan Mode, the indoor fan may operate without the compressor producing cooling.

Similarly, temperature settings can affect perceived performance.

The technician should confirm that the unit is actually operating in cooling mode.

CHECK THE TEMPERATURE SETTING

If the temperature is set close to the room temperature, the compressor may not operate continuously.

For troubleshooting, the technician can select an appropriate cooling setting according to the manufacturer's instructions and observe whether the system responds.

A temperature-control problem may be caused by:

Remote-control settings
Temperature sensor
Control board
Thermistor
Communication problem

DIRTY AIR FILTER

A dirty air filter is one of the simplest causes of poor AC performance.

The indoor unit draws room air through the filter.

When the filter becomes heavily contaminated with:

Dust
Hair
Dirt
Fibers
Smoke residue

airflow can become restricted.

Reduced airflow means less warm air passes across the evaporator coil.

The air conditioner may then struggle to cool the room.

SIGNS OF A DIRTY FILTER

Customers may notice:

Weak airflow
Poor cooling
Increased running time
Ice forming on the evaporator
Unusual smell
Higher electricity consumption
Increased noise

Cleaning or replacing the filter can sometimes restore normal performance.

DIRTY EVAPORATOR COIL

The evaporator coil is located inside the indoor unit.

Over time, dust can accumulate on the coil.

This creates a layer of contamination between the room air and the cold coil surface.

The result can be:

Reduced heat transfer
Weak airflow
Poor cooling
Ice formation
Longer compressor operation

Professional AC cleaning may be required when normal filter cleaning is insufficient.

DIRTY CONDENSER COIL

The outdoor condenser unit releases heat extracted from the room.

If the condenser coil becomes heavily blocked with dust and dirt, heat cannot escape efficiently.

This can cause:

High operating pressure
Compressor overheating
Reduced cooling
Frequent compressor shutdown
Increased electricity consumption

The outdoor condenser should therefore be kept reasonably clean and unobstructed.

OUTDOOR UNIT NOT RUNNING

A split air conditioner depends on both indoor and outdoor units.

If the indoor fan operates but the outdoor unit does not, the system may not cool.

Possible causes include:

Electrical supply problem
Outdoor PCB fault
Contactor problem
Capacitor failure
Compressor fault
Communication fault
Wiring problem
Sensor protection
Control-board fault

The technician should diagnose the outdoor unit rather than simply adding refrigerant.

CONDENSER FAN FAILURE

The outdoor fan helps remove heat from the condenser.

If the fan stops working, the condenser can become excessively hot.

Possible causes include:

Failed fan motor
Capacitor fault
PCB problem
Wiring fault
Mechanical obstruction
Bearing failure

A failed condenser fan can eventually cause compressor protection to activate.

AC COMPRESSOR PROBLEMS

The compressor is a central component of the refrigeration system.

It circulates refrigerant through the cooling circuit.

A compressor can fail electrically or mechanically.

Possible symptoms include:

Compressor does not start
Compressor hums
Compressor trips the breaker
Compressor overheats
Compressor runs continuously
Poor cooling despite apparently normal operation
Unusual vibration

A compressor should not be condemned without appropriate testing.

COMPRESSOR CAPACITOR

Conventional non-inverter air conditioners may use a capacitor to assist compressor starting and operation.

A weak capacitor can cause:

Compressor difficulty starting
Humming
High current
Overheating
Repeated shutdown
Poor cooling

The capacitor should be tested and replaced with an appropriately rated component if necessary.

INVERTER AIR CONDITIONERS

Inverter AC systems operate differently from conventional fixed-speed systems.

An inverter compressor can vary its speed according to cooling demand.

The system may contain:

Inverter compressor
Inverter PCB
Power module
Sensors
Indoor PCB
Outdoor PCB
Communication wiring

A fault in any of these systems can affect cooling.

Inverter AC diagnosis therefore requires knowledge of both refrigeration and electronic control systems.

LOW REFRIGERANT

Low refrigerant can cause poor cooling.

However, refrigerant does not normally disappear simply because an air conditioner has been used for a long time.

If the system is low, there may be a leak or another sealed-system issue.

Possible signs include:

Reduced cooling
Long compressor operation
Partial evaporator frost
Poor temperature drop
Abnormal operating pressures

The technician should determine why the refrigerant level is low.

REFRIGERANT LEAK

A leak can occur at various points in an AC system.

Potential leak locations include:

Flare connections
Copper pipe joints
Brazed joints
Service valves
Coil sections
Condenser
Evaporator
Damaged copper tubing

Simply refilling refrigerant without addressing the leak is not a complete repair.

AC GAS REFILLING

Customers often use the term “AC gas” when referring to refrigerant.

Refrigerant charging should be performed according to the equipment manufacturer's specifications.

The technician should identify:

Refrigerant type
Required charge
System condition
Leak status
Operating conditions

Different air conditioners can use different refrigerants, and the refrigerant type should not be guessed.

ICE ON THE AC PIPE

Ice formation is an important diagnostic symptom.

Customers may see ice around:

Copper suction pipe
Evaporator coil
Indoor unit

Possible causes include:

Restricted airflow
Dirty filter
Dirty evaporator
Low refrigerant
Blower problem
Sensor fault
Refrigeration-system restriction

Ice should not automatically be interpreted as proof of low refrigerant.

AC WATER LEAKING

An indoor AC unit may leak water when condensate cannot drain properly.

Possible causes include:

Blocked drain pipe
Dirty drain tray
Poor installation angle
Broken drain pump
Frozen evaporator
Excessive condensation

The drain system should be inspected carefully.

BLOCKED DRAIN PIPE

Air conditioners remove moisture from indoor air.

That moisture becomes condensate and normally flows through a drain system.

Dust and biological material can accumulate in the drain line.

A blocked drain may cause:

Water dripping from the indoor unit
Wet walls
Wet floors
Water damage
Bad smells

Cleaning the drain system can resolve the problem when blockage is the cause.

AC DRAIN PUMP

Some installations use a condensate pump.

If the pump fails, water may accumulate and eventually leak.

Possible causes include:

Pump motor failure
Float-switch problem
Blocked pipe
Electrical fault
Pump contamination

AC NOT COOLING BUT FAN IS WORKING

This symptom is very common.

The indoor fan may continue operating even when the compressor has stopped.

Potential causes include:

Compressor fault
Outdoor PCB fault
Refrigerant problem
Sensor fault
Capacitor failure
Electrical supply issue
Control communication problem

The technician should inspect both indoor and outdoor units.

WEAK AIRFLOW

Weak airflow can be caused by:

Dirty filters
Dirty evaporator
Fan motor problem
Fan-speed control problem
Blocked air outlet
Blower wheel contamination
Ice formation

Poor airflow should be diagnosed separately from refrigerant problems.

AC FAN MOTOR

The indoor fan motor circulates air through the evaporator.

A failing motor may:

Run slowly
Stop intermittently
Make unusual noises
Overheat
Fail to start

Some modern systems use electronically controlled fan motors.

AC CONTROL BOARD

Modern air conditioners rely heavily on electronic control boards.

A PCB may control:

Compressor operation
Fan speed
Temperature sensing
Communication
Protection systems
Swing motor
Display
Error codes

A damaged PCB can create complicated symptoms.

However, the board should be diagnosed rather than replaced based solely on symptoms.

AC TEMPERATURE SENSOR

The indoor unit commonly uses a temperature sensor or thermistor.

If the sensor incorrectly reports the room temperature, the control system may operate the compressor incorrectly.

Potential symptoms include:

Poor cooling
Compressor stopping too early
Continuous operation
Incorrect display
Error code

AC COMMUNICATION FAULT

Many modern split systems use communication between indoor and outdoor PCBs.

If communication fails, the outdoor unit may not operate correctly.

Potential causes include:

Damaged communication wiring
Loose terminals
PCB failure
Incorrect voltage
Installation error

AC INSTALLATION PROBLEMS

Poor installation can affect AC performance from the beginning.

Possible installation problems include:

Incorrect pipe length
Poor flare connection
Refrigerant leakage
Inadequate vacuuming
Incorrect drainage slope
Poor outdoor-unit ventilation
Incorrect electrical connection
Improper pipe insulation

An air conditioner that has never performed correctly may require installation assessment rather than ordinary maintenance.

COPPER PIPE INSULATION

The copper refrigeration pipes should normally be appropriately insulated.

Damaged or missing insulation can cause:

Condensation
Energy loss
Reduced efficiency
Water dripping
Pipe sweating

The insulation should be inspected during servicing.

AC VACUUMING

During installation or certain refrigeration-system repairs, proper evacuation is important.

Moisture and non-condensable gases can negatively affect refrigeration performance.

A professional technician should use appropriate equipment and procedures when evacuating the system.

AIR CONDITIONER COMPRESSOR REPLACEMENT

Compressor replacement is a major AC repair.

It may involve:

Recovering refrigerant
Disconnecting the electrical supply
Removing the failed compressor
Installing a compatible replacement
Reconnecting refrigeration lines
Replacing relevant components where necessary
Pressure testing
Evacuating the system
Charging refrigerant
Testing system performance

The correct compressor must match the equipment requirements.

AC PIPE WORK

Copper pipe work is an important part of split AC installation and repair.

Problems can include:

Crushed pipe
Kinked pipe
Poor flare
Leaking joint
Incorrect diameter
Poor insulation
Excessive pipe length

Correct pipe installation contributes to reliable cooling.

AC INSTALLATION IN NAIROBI

Air conditioner installation may be required in:

Homes
Offices
Apartments
Hotels
Restaurants
Shops
Hospitals
Schools
Server rooms
Commercial buildings
Workshops
Industrial facilities

The installation should consider room size, heat load, ventilation, electrical supply, drainage and outdoor-unit positioning.

CHOOSING THE RIGHT AC CAPACITY

Air conditioners come in different capacities.

A unit that is too small for the room may run continuously without achieving the desired temperature.

A unit that is excessively large can also create undesirable operating characteristics.

Proper capacity selection should consider:

Room size
Ceiling height
Number of occupants
Windows
Sun exposure
Appliances generating heat
Building insulation
Intended use

AC REPAIR IN NAIROBI

Professional air-conditioning repair services are needed across Nairobi, including:

Nairobi CBD
Luthuli Avenue
Westlands
Parklands
Kilimani
Lavington
Kileleshwa
Hurlingham
Upper Hill
South B
South C
Lang'ata
Karen
Runda
Gigiri
Ruaka
Kasarani
Roysambu
Ngong Road
Kangemi
Dagoretti
Donholm
Umoja
Buruburu
Komarock
Kayole
Embakasi
Industrial Area

Commercial customers may require emergency AC repair when cooling equipment fails during business operations.

COMMERCIAL AIR CONDITIONING REPAIR

Commercial AC systems can include:

Split AC
Cassette AC
Ceiling units
Floor-standing units
Ducted systems
Industrial cooling systems
Portable AC
Server-room cooling equipment

These systems may operate for extended periods and therefore benefit from preventive maintenance.

AC MAINTENANCE

Regular AC maintenance can help identify problems before they become major failures.

Maintenance may include:

Filter cleaning
Evaporator cleaning
Condenser cleaning
Drain cleaning
Fan inspection
Electrical inspection
Refrigeration-system assessment
Temperature testing
Pipe inspection
Remote-control checks
General performance testing

WHY AC MAINTENANCE MATTERS

A dirty AC does not have to wait until it completely stops working.

Poor maintenance can gradually result in:

Weak cooling
Increased power consumption
Ice formation
Water leakage
Fan problems
Compressor stress
Poor indoor air quality
Unpleasant smells

Preventive maintenance can therefore be more economical than waiting for a major failure.

AIR CONDITIONER BAD SMELL

A bad smell from an AC may be caused by:

Dirty evaporator
Dirty filter
Moisture accumulation
Blocked drain
Contamination
Microbial growth
Dirty blower assembly

Cleaning should address the actual source rather than simply masking the smell with fragrance.

AC MAKING NOISE

Different noises can provide diagnostic clues.

Possible sounds include:

Humming
Clicking
Rattling
Grinding
Vibrating
Whistling
Buzzing

Potential causes include:

Loose panels
Fan problems
Compressor vibration
Bearing problems
Foreign objects
Electrical components

Unusual noises should be investigated before they develop into larger problems.

AC KEEPS TURNING ON AND OFF

Frequent cycling can have several causes.

Possible reasons include:

Incorrect temperature sensing
Oversized system
Refrigeration problem
Compressor protection
Electrical problem
Dirty condenser
Control-board fault

A technician should determine whether the cycling is normal for the specific system or represents a fault.

AC NOT TURNING ON

If the air conditioner does not start at all, check:

Mains supply
Isolator
Circuit breaker
Remote batteries
Indoor PCB
Fuse
Wiring
Error indications

The simplest causes should be eliminated before deeper electronic diagnosis.

AC REMOTE CONTROL PROBLEMS

Sometimes the air conditioner itself is functional but the remote control is not communicating correctly.

Possible causes include:

Dead batteries
Damaged remote
Incorrect mode
Infrared transmitter problem
Receiver problem

The appliance should be tested using appropriate controls before concluding that a major repair is necessary.

AC REPAIR AND SAFETY

Air-conditioning repair involves electricity, rotating machinery, pressurized refrigeration circuits and potentially hazardous electrical components.

Technicians should use:

Appropriate PPE
Correct test equipment
Proper isolation procedures
Refrigeration service tools
Appropriate leak-detection methods
Manufacturer specifications

Electrical panels and refrigeration systems should not be opened or serviced by unqualified persons.

DO NOT JUST ADD GAS

This deserves special emphasis.

If an AC is not cooling, simply adding refrigerant may temporarily change the symptoms without solving the underlying fault.

A professional diagnosis should determine whether:

Refrigerant is actually low.
There is a leak.
Airflow is restricted.
The condenser is dirty.
The compressor is operating correctly.
The expansion device is functioning.
Sensors are working.
The control system is operating correctly.

AC SPARE PARTS

Common air-conditioner spare parts include:

Compressors
Capacitors
Fan motors
PCBs
Sensors
Thermistors
Relays
Contactors
Expansion components
Copper pipes
Drain pumps
Remote controls
Filters
Blower motors
Condenser motors

Parts should be matched to the specific model.

AIR CONDITIONER BRANDS

Technicians in Nairobi may encounter equipment from brands such as:

Samsung
LG
Hisense
TCL
Midea
Gree
Daikin
Carrier
Haier
Panasonic
Mitsubishi
Sharp
Von
Ramtons

Different brands and models use different control systems and refrigeration configurations.

PROFESSIONAL AC DIAGNOSTIC PROCEDURE

A technician can follow a systematic approach.

STEP 1: CONFIRM THE CUSTOMER'S COMPLAINT

Determine whether the problem is no cooling, weak cooling, intermittent cooling, water leakage, noise or complete failure.

STEP 2: CHECK THE OPERATING MODE

Confirm that the unit is in cooling mode.

STEP 3: CHECK AIRFLOW

Inspect filters, evaporator and blower.

STEP 4: CHECK THE OUTDOOR UNIT

Confirm that the condenser fan and compressor operate correctly.

STEP 5: CHECK ELECTRICAL SUPPLY

Verify appropriate power and control signals.

STEP 6: CHECK TEMPERATURE SENSORS

Inspect relevant thermistors and sensors.

STEP 7: INSPECT THE CONDENSER

Check for dirt and airflow restrictions.

STEP 8: ASSESS THE REFRIGERATION CIRCUIT

Where indicated, assess refrigerant conditions and system performance.

STEP 9: CHECK FOR LEAKS

If refrigerant loss is suspected, locate the source rather than simply recharging repeatedly.

STEP 10: TEST THE SYSTEM

After repair, verify cooling performance and normal operation.

WHEN TO REPLACE AN AC

Repair may be preferable when:

The compressor is healthy.
Spare parts are available.
The system is otherwise in good condition.
The repair is economical.

Replacement may be considered when:

The system is severely damaged.
Major components have failed.
Spare parts are unavailable.
The system is extremely inefficient.
Repair costs approach replacement cost.

PROFESSIONAL AIR CONDITIONING SERVICES IN NAIROBI

Pro-Logic Technologies Limited provides appliance and technical repair services, including air-conditioning repair and installation.

For service enquiries:

Phone: 0723763173

Email: info@prologictechnologies.co.ke

Main Workshop: Luthuli Avenue, Kangari Building, 3rd Floor, KA7, Nairobi.

Customers can seek assistance for air-conditioner troubleshooting, servicing, repair, installation, compressor-related faults, fan problems, electrical faults, cooling problems and other AC-related issues.

AC REPAIR FOR HOMES AND BUSINESSES

Residential air-conditioning problems can make bedrooms, living rooms and home offices uncomfortable.

Commercial AC problems can affect:

Staff comfort
Customer experience
Office productivity
Server equipment
Hotel operations
Restaurant operations
Business continuity

For this reason, prompt diagnosis can be valuable when an AC begins showing signs of poor performance.

CUSTOMER QUESTIONS

Why is my AC running but not cooling?

Possible causes include dirty filters, restricted airflow, refrigerant problems, condenser contamination, compressor faults, sensor problems or control-board faults.

Does poor cooling always mean low gas?

No. Airflow, electrical, compressor, sensor and control problems can also cause poor cooling.

Why is my AC freezing?

Possible causes include restricted airflow, low refrigerant, dirty evaporator, fan problems or sensor faults.

Why is water dripping from my indoor AC?

A blocked drain, frozen evaporator, poor drainage installation or condensate-pump fault can cause water leakage.

Why does the outdoor unit not start?

Possible causes include electrical supply problems, control-board faults, compressor issues, capacitor failure, communication faults or protective shutdown.

Why does my AC make unusual noises?

Possible causes include fan problems, loose components, compressor vibration, foreign objects or worn mechanical parts.

How often should an AC be serviced?

Service frequency depends on usage, environment and equipment type. Systems operating heavily or in dusty environments may require more frequent cleaning and inspection.

Can an inverter AC be repaired?

Yes. Inverter systems can be repaired, but diagnosis may require specialized knowledge of inverter electronics, sensors, compressor control and communication systems.

FINAL AC REPAIR CHECKLIST

Before completing an air-conditioning repair, the technician should verify:

Correct operating mode
Electrical supply
Indoor fan
Outdoor fan
Compressor
Temperature sensors
Filters
Evaporator
Condenser
Drainage
Refrigeration circuit
Refrigerant condition
Copper piping
Pipe insulation
Control boards
Communication
Final cooling performance

An air conditioner that is running but not cooling should therefore be diagnosed systematically. The correct repair may involve cleaning, electrical repair, fan replacement, sensor replacement, drainage repair, control-board repair, compressor replacement or refrigeration-system service.

The key principle is simple:

Diagnose the actual fault before replacing parts or adding refrigerant.

For professional air conditioner repair and installation in Nairobi, contact Pro-Logic Technologies Limited.

0723763173

info@prologictechnologies.co.ke

Luthuli Avenue, Kangari Building, 3rd Floor, KA7, Nairobi.