Skip to content
REFRIGERATION

Troubleshooting

Visi cooler light flickering

In a glass-door merchandiser the lighting sells the product. A flickering or dim light makes a cooler look faulty to customers even when it is cooling perfectly. Most modern coolers use LED strips or tubes driven by a small power supply. LEDs themselves last a long time, but their drivers and connectors are sensitive to heat, voltage spikes and moisture, all of which Indian shops supply in quantity. Flicker is usually a supply, connection or driver issue rather than the LEDs themselves. Since lighting circuits are inside covers and run from mains-powered drivers, most fixes are for a technician.

First, check these

  1. Check whether other lights in the shop flicker at the same time. If so, the supply voltage is fluctuating, not the cooler.
  2. Open and close the door. If the light changes, the door switch or door-linked lighting may be involved.
  3. Check if a light switch or controller lighting setting has been changed, such as a timer or night mode dimming.
  4. Look for condensation or water droplets inside the light cover, common in monsoon months.
  5. Check the light is the only problem. If the cabinet temperature, fans and display are normal, the cooling system is probably fine and stock is safe.

Likely causes

  1. 1. Supply voltage fluctuating

    Technician job

    Signs: Flicker coincides with other appliances starting or with the evening peak; other lights also flicker.

    Fix: Have an electrician check the supply. A stabiliser or voltage protector also protects the compressor and controller.

  2. 2. Lighting timer or energy-saving setting

    You can check this

    Signs: Lights dim or switch at set times, often at night.

    Fix: Check the controller or lighting switch settings in the manual and set them to suit your opening hours.

  3. 3. Loose connector or worn door switch

    Technician job

    Signs: Flicker when the door moves or the cabinet is bumped; light works intermittently.

    Fix: A technician should check and secure the connectors and replace a faulty door switch.

  4. 4. LED driver failing

    Technician job

    Signs: Flicker gets worse over weeks, or lights dim and then go out; sometimes after a voltage spike.

    Fix: A technician replaces the driver with a compatible part. Do not fit a random replacement driver.

  5. 5. Moisture in the light fitting

    Technician job

    Signs: Droplets inside the cover, corrosion on contacts, flicker worst in humid weather.

    Fix: Isolate power and have a technician dry, reseal or replace the fitting. Fix the door seal if humid air is getting in.

  6. 6. LED strip or tube at end of life

    Technician job

    Signs: Part of the strip is dark or one section flickers while the rest is fine.

    Fix: A technician replaces the strip or tube with the correct type for the cooler.

When to call a technician

Call a technician if flicker continues with stable supply and correct settings, if lights have gone out, or if moisture is inside the fitting. Tell them whether the flicker is constant, linked to the door or linked to time of day. Lighting faults usually do not affect cooling, but a driver that failed after a voltage spike can be a warning that other electronics took a hit too.

Isolate power before cleaning around light covers and never open a light fitting or driver while the unit is plugged in. Water near lighting is a shock risk. Hydrocarbon refrigerant (R290 or R600a) units must only be opened by trained technicians.

Book a service visit