Updated at: 10-05-2022 - By: Sienna Lewis

There are telltale symptoms and estimated lifespans to keep in mind if you’re trying to figure out if an HPS bulb is burned out. Gardeners are familiar with the fact that HPS bulbs need to be replaced more frequently than LED lights. However, it’s not always evident when they need to be replaced, and the last thing you want to do is change them prematurely.

In the early phases of a plant’s development, it’s critical to keep the light source working at its peak efficiency. Consequently, cleaning and checking the temperature and humidity in the greenhouse are only the beginning of greenhouse maintenance. The gardener must also be aware of the telltale indicators of burned-out HPS bulbs and when to replace them.

How To Tell If A HPS Bulb Is Burnt Out And What To Expect

Signs to look out for

It’s best to check the base of the bulbs if they’ve turned black. This does not, however, imply that you should wait for the occurrence of this bodily symptom. Due to their short lifespan of 8000 to 16000 hours, some gardeners choose to replace their HPS bulbs every four or three harvests.

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As a result, while the visible indicator of a darkened base may be absent, the bulbs’ lumen output may have already decreased. Keep both of these suggestions in mind in case this loss results in production issues. A darkening of the base on the fourth harvest indicates that the bulb is near to exploding.

When HPS lamps flicker excessively or shut off altogether, they are most likely burned out. They should be replaced since they can reduce the color spectrum. Remember that the spectrum also plays a key influence in the growth lights’ efficiency, so if the bulb appears whiter than usual, it’s time to replace it.

How Often Should You Replace An HPS Bulb

HPS bulbs should be replaced every six to ten months if they are used continuously by experienced growers. For maximum performance, you should change them once a year if you’re using them for a 12-hour on, 12-hour off cycle. When it comes to HPS bulbs, you’ll only need to replace them every eight months if they’re on for 18 hours a day and off for six.

That’s why HPS bulbs with a blue spectrum, as previously noted, need to be replaced sooner because the spectrum itself is degrading. Knowing when an HPS bulb is degrading is critical since it affects your yield. To put it another way, a 20% decrease in output is equivalent to a 20% decrease in yield.

If you observe any darkening on the ends of the inner arc tube, you may need to replace it sooner rather than later. This could be a sign of exhaustion, but the dark coloring will also prevent light from passing through. The HPS bulb’s lifespan will be shortened if there are frequent power interruptions.

Signs that the HPS bulbs are damaged or used

There will be times when you doubt the freshness of your HPS bulbs. Black flecks on the element’s underside indicate manipulation, so look for those if you have any doubts. Always inspect bulbs before using them because they can be damaged during shipping and produce scuffs on the base connections.

How To Tell If A High Pressure Sodium Bulb Is Bad

When the bulb does not light up, it is time to replace it. Look at the little tube inside the bulb for a less sarcastic response.

If the tube has a dark or even black appearance, it is dead and unable to be recharged. Sarcastic responses, on the other hand, are the most effective means of verifying Take the time to put all of your new bulbs to the test as soon as you receive them.

Why Do HPS Bulbs Go Bad?

High-pressure sodium bulbs, like any other light bulb, eventually burn out. The arc tube within these “bulbs”—really “lamps”—is what powers them.

The lamp’s arc tube is critical to its operation. Heavily-pressurized gas fills it. When the bulb is operating, it emits a bluish glow because of the presence of mercury.

Other than sodium vapor, which is what gives HPS lamps their name, there is another ingredient inside.

Lighters do not ignite anything except for oxygen and water vapor, leaving sodium vapor completely unaffected. To make the blueish light more tolerable, sodium is burned to produce a warm white light.

As you can see, a high pressure sodium lamp contains a plethora of gases and scientific components. In order for the lamp to perform properly, it is necessary to maintain a tight vacuum seal.

It is difficult to keep this seal in good working order. Oxygen and other contaminants will seep into the seal over time, contaminating the gas mixture and causing it to expire much more quickly.

When the tube inside the bulb becomes contaminated, the game is over and the lamp ceases to work.

Other Reasons HPS Lamps Stop Working Or Work Improperly

HPS bulbs fail due to deterioration over time, however this isn’t the sole factor. The following can also lead to the failure of an HPS light.

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Voltage Irregularities

A stable voltage is needed to maintain the HPS lights’ insane output of clear, bright light. Between 50 and 100 volts must be applied to the tube.

It can cause the bulb to look dull, discolored, or too brilliant if the voltage is too high or too low for an extended period of time.

Consistently fluctuating voltage will shorten the life of the lamp. The fact that they’re not inexpensive is bad.

Fixture Wiring Issues

A lamp cannot operate on its own; it must be connected to a fixture in order to work. Occasionally, a loose solder connection or frayed wire inside the fixture might produce voltage abnormalities or other problems that can impact the HPS light.

To avoid this, invest a little more money on high-quality HID lighting fixtures.

Other Fixture Issues

If a fixture’s capacitor is old or incorrectly wired, it can create significant voltage spikes and dips, which we already know is hazardous for a bulb.

Capacitor input and output voltages can easily measured with a multimeter. The ballast is the same. Check the voltages of the bulb’s input and output to determine which of these components is causing the problem. Make sure the ballast hasn’t been dimmed.

The Bulb Itself

Porcelain is a brittle and fragile material, hence the bulb’s porcelain base might easily shatter. The outside air can get inside the bulb if the base is fractured, which is not a good thing.

Aside from the porcelain base, there are also places of touch. Check for any evidence of damage on those. If you see any of these signs on your bulb, it’s time to replace it because the bulb will most likely go bad shortly if left alone.

How To Test A High Pressure Sodium Bulb

Put it in a light fixture and run the test, that’s the only way to be sure. In the event that you are trying to determine whether a bulb or a fixture is faulty, consider using it in an another fixture that works.

The various approaches outlined in this section can also be used to test for any of these concerns.

How Long Do HPS Bulbs Last?

The answer is two-fold. It takes roughly 25,000 hours for the best high-pressure sodium bulbs to burn out. You can round up or round down to the nearest few weeks or months to arrive at an approximate 3-year timeline.

You may be confident that your money will be wisely spent on this. To be clear, this is a two-part response, as I said before.

You should replace your lamps every 18 months if you keep plants indoors, which I’m sure you do. This is a significantly smaller window of opportunity than you’d see during usual usage.

Why Do I Need To Replace It So Often As A Grower?

Consistent light strength is critical to the success of cannabis cultivation. Over time, the gasses in HPS lamps weaken as more of them slowly and inevitably seep out or decay.

Cannabis is a natural plant that, according to theory, should receive all of its energy from the sun. Despite its inconsistencies, the sun’s output is far more consistent than any light bulb, particularly high-pressure sodium.

The bulb gradually weakens over time. It will take your plants some time to adjust to the new lighting, but you won’t.

The bulb’s strength will deteriorate with time, and if it weakens during flowering and you don’t notice, you could be reducing your harvest’s yield!

Optimum Usage Of HPS Bulbs For Cannabis Growers

Bulbs should be replaced according to a set schedule for expert growers. There is a wide range of opinions on how often to change them, and some people think it’s too extreme.

Most professional growers lean on the side of replacing the lamps every two to three grows, which appears to be the medium ground. If you choose to ignore this pricey recommendation, that’s entirely up to you.

Considerations On HPS Lamp Replacement Frequency

As crucial as feeding your plants nutrients and water is the quality and intensity of light they get. As a result, it makes sense to acquire a new high-pressure sodium lamp every two or three crops when you consider your harvest’s output.

Growers that use high-quality and consistent lighting in their setups are more likely to produce large- and heavy-bud yields.

Do not cut corners when it comes to lighting in your business. In terms of the size of your harvest, they have a significant impact.

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In order to guarantee that your plants receive all of the nutrients they require, regular maintenance of the greenhouse is essential. Are you confident in your ability to identify if an HPS bulb has gone out? Initially, you might look for some darkening at the base to see if it’s aging.

In addition, keep track of when your bulbs are expected to fail. It is possible that you will need to replace them even if this is not your fourth harvest or if the harvest is more than ten months away, depending on their daily experience. Degradation causes low power and low yield, therefore don’t wait for the bulbs to burn out before replacing them.