Why Do My Lights Flicker When The Water Heater Is On?

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When the water heater is turned on, the voltage declines as a result of the increased current demand. This causes lights to flicker. Electric motors, in particular, require a large amount of initial startup current. Even though it looks like a minimal problem, you should not ignore it.

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Can A Water Heater Cause Lights To Flicker?

A water heater can cause lights to flicker. For instance, tankless water heaters have numerous advantages, but they also cause LEDs to flicker. When the light flickers coincide with when the hot water is turned on, such as when someone is in the shower, the water heater is most likely to blame.

A water heater is a large electric load that cycles on and off to maintain the right temperature of your water. Every time it cycles, it activates its heating element, which consumes a significant amount of electricity.

Large electrical loads are accompanied by large electrical currents, which are significantly higher when they are first turned on. When your electric panel is subjected to high currents, every load in the panel experiences a voltage drop.

The service wires experience exceptionally high current, amperes, as the water heater element transitions from no load to full load. Even appropriately designed cables have significant “voltage drop” when strong currents pass through them, which is why your light flickers.

These heaters use so much energy that they can wreak havoc on the voltage delivered to other parts of your house while they’re on, causing lights to flicker. Upgrade your light bulbs. If that doesn’t work, you’ll probably need to hire an electrician.

It may not be a problem if the flickering is sporadic, small, and occurs just momentarily when the appliance is turned on. When large electrical appliances are turned on, they draw more current. This results in a voltage loss, which causes the lights to flicker or fade. The better the system design is, the less visible it is.

There is an issue if the flickering occurs frequently and is strong. The problem may be with the appliance itself. When a bearing fails, for example, the motor will use greater current as it tries to start. It’s also possible that there’s too much sensory stimulation on the same circuit.

Why Do My Lights Flicker When The Water Heater Is On?

A water heater is made out of a resistive heater coil that has some stray inductance. This stray inductance opposes any abrupt changes in the current flowing through it by producing a reverse emf that opposes the change’s cause.

When you turn on/off the heater, there is a huge change in current in a short period, resulting in back emf, which is visible as a voltage spike and ripple in the line to which the heater is connected. As a result, a light bulb connected to the same line will be affected by the ripple, resulting in a temporary flickering.

The flickering isn’t a big deal as long as it’s only for a few seconds. Nonetheless, it shows that the current demand is approaching the capacity of your system. If the problem persists, you might want to consider getting a larger service panel installed.

Most modern residences should have at least a 150 amp service, with a 200 amp service being preferable, especially if they have electric hot water and/or heat.

The following are the probable reasons for the flickering:

Circuit Is Overloaded

The electrical panel in your home has a lot of different circuits, and many of them deliver electricity to various electrical objects on the same breaker, from track lighting to the refrigerator.

When the heater is turned on, it draws a surge of electricity from the circuit to power the fan. As a result, any light fixtures on the same circuit as the heater may flicker due to a temporary reduction in electrical supply.

Flickering lights indicate that the circuit is reaching an overload, and the breaker may trip due to the excessive amount of electricity required. To avoid any light flickering, the heater should ideally have its circuit and breaker.

Loose Wiring Connections

Flickering lights are produced by faulty wiring, which is also one of the primary causes of house fires. It doesn’t matter if the problem is broad or limited to a specific place; it’s always harmful.

A high resistance point is formed when a circuit connection is loose, which leads to dangerous point heating. A single faulty connection might jeopardize the entire system.

Maximum Distribution Panel

The electrical supply in a home is limited; the distribution or electrical panel can only safely send a certain amount of voltage and current throughout the structure.

If you have added new circuit breakers or major appliances to the home, such as a second freezer in the garage, the activation of the heater may overload the entire home’s distribution panel.

The heater, in effect, consumes the last of the house’s electricity, causing the lights to flicker. A certified electrician should be consulted if there are any issues with the electrical panel’s maximum capacity.

Arcing

Sheathing is important to completely encase all electrical cables; any exposed bare wires can potentially cause a fire. To see if any wires are exposed, check at the heater’s power cord.

Arcing between various wires can be caused by even a slight breach in the cord’s covering. Arcing is an electrical short between two wires in which electricity skips across from one to the other. The wires become heated as a result, and they may catch fire.

Any exposed wires should be avoided; you should immediately contact an electrician and turn off the circuit breaker for that circuit.

Is It Bad If Your Lights Flicker?

Flickering lights or dimming lights in a house might be inconvenient in addition to being bothersome but there is usually a benign reason for the flickering.

Flickering lights, on the other hand, may indicate a wider problem with your electrical system, in which case neglecting the problem could result in dangerous consequences such as home fires.

Home electrical fires cause $1.3 billion in property damage and over 500 deaths each year, according to the Electrical Safety Foundation International.

Investigate the issue further before becoming concerned. By watching the flickering pattern—when it happens, for how long, how frequently, and so on—you can then typically pinpoint the reason for flickering lights.

If you live with flickering lights, you’re well aware that they’re more than a minor annoyance. Our homes are comfortable and safe because of power, but difficulties with electricity put them in jeopardy.

Never attempt to fix significant electrical problems yourself for your own safety’s sake. If you’ve had it with your flickering lights, contact a local electric company right away.

Until an electrician can assess the system, you can temporarily stop the flickering by disconnecting other electrical equipment from the circuit.

You can unplug any unnecessary items from the wall outlets in addition to turning off the heater; this operation spares the electrical panel from giving more electricity to other items. When there are fewer appliances and devices drawing electricity from the electrical panel, the lights should not flicker.