The monitor turns off when the refrigerator starts: what to do and how to fix it

The situation is familiar to many: you are working at a computer, and when the refrigerator starts, the monitor screen goes dark for a second or turns off completely. Sometimes the problem is accompanied by relay clicks, flickering lamps, or even rebooting of all equipment in the house. What is it - a malfunction of the monitor, problems with the refrigerator, or hidden defects in the electrical wiring?

In practice 90% of cases they are not associated with the breakdown of devices, but with the peculiarities of their joint operation in the same electrical network. A refrigerator is one of the most energy-intensive household appliances: when the compressor starts, it consumes 5–7 times the rated current. This load can cause a voltage drop, to which monitor power supplies are sensitive, especially modern ones with thin protection circuits.

In this article we will analyze all possible reasons - from the banal network overvoltage to rare malfunctions in the connection circuit. You will learn how to independently diagnose the problem, what measures will help eliminate it without calling an electrician, and in which cases you cannot do without professional help.

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1. Voltage drop when starting the compressor

The main reason the monitor turns off is voltage surge at the moment the refrigerator is turned on. The compressor (the heart of the refrigeration system) at startup consumes a current 5–8 times higher than the operating current. For example, if the passport indicates 150 W, then the starting current can reach 700–1200 W. This load causes a short-term drop in voltage in the network, to which the monitor power supplies react.

Particularly vulnerable:

• 🖥️ Monitors with switching power supplies (thin LED screens, gaming models with high refresh rates). They are sensitive to voltage fluctuations and can turn off when they fall below 190–200 V.
• 🔌 Poor quality extension cords and surge protectors. Cheap models cannot handle inrush currents and “sag” along with the network.
• 🏠 Old wiring. Aluminum wires or cables with a cross-section of less than 2.5 mm² create additional resistance, exacerbating subsidence.

How to check? Use with a multimeter in voltage measurement mode. Plug it into the outlet and start the refrigerator. If, when the compressor starts, the readings drop below 190 V the problem is confirmed. A critical drop to 170-180 V can damage not only the monitor, but also other devices (routers, hard drives). disks).

2. Malfunctions in the electrical wiring of the apartment

If a voltage drop is observed only in one room or on a separate line, it is to blame local wiring. Frequent reasons:

• 🔥 Poor contact in the outlet or junction box. Oxidized or loose connections create additional resistance that increases subsidence.
• ⚡ Insufficient cable cross-section. For a refrigerator and a computer on the same line, a cable 2.5 mm² (copper) is recommended. Aluminum wires or cross-section 1.5 mm² cannot cope with the load.
• 🔌 "Weak" socket. Cheap sockets without grounding or with worn contacts can overheat and “sag” under load.

How to diagnose?

1. Check the temperature of the socket by hand after operating the refrigerator. If it is warm, the contacts are loose.
2. Connect the monitor to another outlet (preferably on a separate line, for example, in the corridor). If the problem disappears, the local wiring is to blame.
3. Inspect the refrigerator plug: melted contacts or blackening are a sign of overheating.

3. Problems with the monitor's power supply

If the voltage drop is minimal (for example, up to 200–210 V), but the monitor still turns off, it is to blame power supply unit (PSU). Modern monitors are equipped with surge protection, but sometimes it works too aggressively. Frequent "culprits":

• 🔌 Power supplies without PFC (power factor correction). They are sensitive to waveform distortion that occurs when the compressor starts.
• 💻 Monitors with external power supplies (for example, some models Dell, HP or AOC). Their adapters often do not have sufficient protection.
• ⚡ Worn capacitors in the power supply. Over time, they lose capacity and cannot filter out interference.

How to check?

1. Connect the monitor to uninterruptible power supply (UPS). If the problem disappears, the monitor's power supply is to blame.
2. Try a different power cable (sometimes the problem is damaged insulation or contacts).
3. Look at the monitor indicators: if it goes out completely (without blinking the light), this is a sign of a shutdown on nutrition. If the light is blinking, the problem may be in the signal cable (HDMI/DisplayPort).

How to check the capacitors in the power supply?

If you are knowledgeable in electronics, you can open the monitor's power supply (disconnecting it from the network!) and inspect the capacitors. Swollen, drips or corrosion on the legs is a sign of a malfunction. It is better to trust the replacement of capacitors the master, since a soldering iron and precise selection of capacity are required.

4. The influence of other household appliances on the network

The refrigerator rarely works alone. If other powerful devices are turned on at the time of its startup (for example, microwave, washing machine or air conditioner), drawdown occurs. voltage increases. The situation is especially critical when:

• 🔌 All appliances are connected to one outlet via extension cord.
• ⚡ In the house single-phase network (typical for old houses), and the load is distributed unevenly.
• 💡 Are used halogen lamps or incandescent lamps, which also create starting currents.

The solution is simple: distribute the load. For example:

5. Refrigerator malfunctions: when. Compressor is at fault

Rarely, but the problem lies in the refrigerator itself. Signs of a malfunction of the compressor or start relay:

• 🔊 Loud clicks at start-up (protection is triggered).
• 🕒 Long start-up (the compressor “presses” for 5-10 seconds before starting).
• ⚡ Voltage sag is stronger than usual (below 180 V).

Frequent reasons:

1. Wear of the starting relay. Over time, the contacts burn out, and the relay begins to “stick”, causing current surges.
2. Compressor jamming. If the motor cannot turn over the first time, it consumes increased current.
3. Refrigerant leak. At low pressure, the compressor operates with overload.

How to diagnose?

If you are not a specialist, it is better to call a specialist. You can do it yourself:

1. Listen to the refrigerator: normal startup is one click of the relay and a smooth hum of the compressormultiple clicks or grinding sounds - a sign. problems.
2. Touch the compressor (carefully - it may be hot!). If it excessive heats up or vibrates, wear is possible.

Loud clicks when starting|Prolonged hum before start|Intense heating of the compressor housing|Frequent shutdowns of the refrigerator (does not maintain temperature)

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6. Solutions: from simple to radical

Depending on the cause, methods for eliminating the problem vary from trivial to requiring intervention. specialist.

Quick solutions (you can do it yourself)

• 🔌 Connect the monitor via a UPS. Even an inexpensive model will smooth out voltage sags. 500 VA will smooth out voltage sags.
• 🔄 Reconnect the refrigerator and monitor to different sockets (preferably on different lines).
• 🛠️ Replace extension cord to a high-quality surge protector with surge protection (for example, APC or Pilot).

Average in complexity (requires tools)

• 🔧 Check and tighten the contacts in the socket, refrigerator plug and machine in the panel.
• 🔩 Replace the socket to a new one with grounding (if the wiring allows).
• 📊 Install a priority relay (for private homes). It will turn off less important appliances when the refrigerator starts.

Radical measures (require a specialist)

• ⚡ Replacement of wiring to copper with cross-section 2.5 mm² (for refrigerator and computer).
• 🔄 Installing a voltage stabilizer for the entire apartment (relevant for houses with an old network).
• 🛠️ Repairing or replacing a refrigerator compressor (for mechanical faults).

⚠️ Attention! If, when starting the refrigerator, not only the monitor goes out, but also the light in the apartment is flashing or the automatic switch is triggered, the problem may be in in the common riser or transformer substation. In this case, contact the management company - independent repair is dangerous!

7. Prevention: how to avoid problems in the future

To prevent the monitor from turning off when starting the refrigerator, follow these simple rules:

• 🔌 Do not connect the refrigerator through an extension cord. Use only a standard outlet.
• ⚡ Share the load: refrigerator, the computer and the microwave must be on different lines.
• 🛡️ Use surge protectors with protection for sensitive equipment (monitors, routers, external hard drives).
• 🔄 Periodically check the voltage in the network Normal. — 220–230 V without drops below 200 V.
• 🛠️ Monitor the condition of the refrigerator: clean the capacitor (grid at the back), do not place it close to the wall.

If you live in a private house or an old building, consider installing a stabilizer. voltage this will protect not only the monitor, but also other equipment from surges.

⚠️ Attention! Cheap "stabilizers" from Chinese online stores often cannot cope with real loads. For a refrigerator and computer, choose models with with a power of at least 2 kW and reaction time <20 ms (for example, Resanta or Calm).

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FAQ: Frequently asked questions

The monitor turns off only at night, when the refrigerator starts up more often. Why?

At night, the temperature in the room is usually lower, and the refrigerator turns on more often to maintain the set mode. In addition, at night, the voltage in the network may be lower due to the characteristics of the transformer substations. The combination of these factors increases the drawdown.

Solution: connect the monitor via a UPS or check the voltage in the outlet at night.

After turning off the monitor, it does not turn back on. What should I do?

If the monitor does not respond to the power button, the problem may be:

1. Power supply —try a different cable or connect the monitor to a different outlet.
2. Capacitors —if the monitor is old, they could fail from a power surge.
3. Motherboard —in rare cases, a sag can damage the power controller.

First, unplug the monitor for 10 minutes (to reset the protection), then try turning it on again. If that doesn’t help, contact the service.

The refrigerator is new, but the problem is still there?

Modern refrigerators with inverter compressors (LG, Samsung, Boschconsume less energy in operating mode, but they starting currents may be even higher due to the control electronics. Check:

• Refrigerator settings: mode Eco or Holiday can reduce the load.
• Connection: inverter models are sensitive to the quality of the socket - use only grounded ones.

Can this damage the monitor or refrigerator?

Short-term voltage dips usually do not harm equipment, but long or deep drops (below (if the computer also turns off). can:

• Lead to wear of capacitors in the monitor power supply.
• Disable hard drives or SSD (if the computer also turns off).
• Shorten service life refrigerator compressor due to increased loads.

If the problem occurs regularly, be sure to take action (UPS, stabilizer, replacement of wiring).

Which UPS to choose for a monitor and computer?

Minimum requirements:

• Power: no less 500 VA (for office PC + monitor For gaming systems - from 1000 VA.
• Type: Line-Interactive (smoothes drawdowns) or Online (full protection, but more expensive).
• Battery life: 5–10 minutes is enough to shut down the PC correctly.
• Sockets: there should be enough ports for the monitor, system unit and router.

Popular models: APC Back-UPS 600, Ippon Smart Power Pro 1000, CyberPower CP685AVR.