PetraTools HD4000 4 Gallon Battery Backpack Sprayer, 6-8 Hr Runtime, Up to 90 PSI

Description

If you have ever wrestled with a hand pump mid-spray, you will appreciate what the PetraTools HD4000 battery powered backpack sprayer brings to the job. This 4 gallon, electric garden sprayer delivers long, continuous spraying on a single charge, adjustable pressure up to a high output, and six included nozzles so you can dial in everything from a fine foliar mist to a targeted stream. It is built for comfort with padded straps and a back pad, which makes longer sessions for pest control or fertilizing easier on your shoulders and lower back.

Key Customer Benefits

• Spray for hours without stopping to pump, thanks to the HD4000’s long-lasting battery and efficient 40 to 90 PSI pressure range. Continuous pressure means steadier droplet size, more even coverage, and fewer streaks on lawns or shrubs. PetraTools lists a 6 to 8 hour spray window on a single charge, with the pump rated to move more than 200 gallons per charge, which is plenty for quarterly perimeter sprays or multi-zone turf treatments.
• Dial in your pattern for every task, from a gentle foliar mist to a targeted jet for cracks and crevices. The six included nozzles are not gimmicks, they have clear jobs. The orange cone reaches about 8 to 10 feet for tree canopies, the double and single mist tips lay down fine droplets for fungicides, and the brass or black tip can be twisted to a straight stream that can shoot over 20 feet for hard-to-reach spots.
• Comfort that actually lasts on your back, with double-padded shoulder straps and a back pad that spreads the load. When you are walking fence lines or treating fruit trees, that cushion and weight distribution make a real difference in fatigue and accuracy at the wand.
• Cleaner fills and fewer clogs, because the wide-mouth lid has a built-in mesh screen that strains debris before it ever reaches the pump. Pair that with the translucent 4 gallon tank and molded volume marks, and you can mix accurately, see your remaining solution, and keep the plumbing clear.
• Easy to operate and maintain for the long haul, with a simple rocker power switch, a pressure knob you can set by feel, front indicator lights for power and charge status, and a user-accessible battery compartment. PetraTools support pages even walk you through quick checks like the fuse and battery connections, which helps you fix most hiccups on the spot.
• Built to handle real pest control work, using a heavy-duty wand, a squeeze trigger with lock, and leak-resistant fittings. Whether you are putting down herbicide on a windy shoulder season day or a perimeter insecticide ahead of ant season, the constant-pressure pump helps you stay precise instead of pumping and praying.

Product Description

What is this

The PetraTools HD4000 is a battery powered backpack sprayer with a 4 gallon translucent tank, a 12-volt 8 amp-hour sealed battery, and a variable output you can set for delicate foliar work or heavier perimeter sprays. Out of the box you get six spray nozzles, an extendable HD wand, a 4-foot hose, charger, and padded harness, which turns long spray days into steady, even application instead of stop-and-pump fatigue. PetraTools advertises 6 to 8 hours of runtime and more than 200 gallons per charge. The Amazon listing specifies the 12V 8Ah battery and lists the adjustable pressure range as roughly 40 to 90 PSI, while the product page emphasizes continuous pressure and comfort-focused straps.

How it works, step by step

Under the tank, a 12V pump draws through a wide-mouth lid with a mesh screen that strains debris before it can ever reach the pump chamber. You set pressure using the silver knob on the control panel, flip the rocker switch to power the unit, then control flow with the squeeze trigger on the wand. The manual walks you through assembly in minutes, priming the pump before first use, and the basic maintenance loop of rinsing, soaping, and flushing with clean water after each job. Petra’s support articles also show simple field checks like verifying the indicator lights, pulling the in-line fuse, and confirming battery charge if the unit does not power on.

What makes it effective and different

For pest control and lawn applications, constant pressure matters because it stabilizes droplet size and coverage. You do not chase a falling spray pattern like you would with a manual pump. University extension work is clear on this principle. Pressure affects droplet size, coverage, and drift risk. Lower pressures give larger droplets with less drift potential. Higher pressures create finer droplets that can improve canopy coverage yet demand more care in breezy conditions. The key is having an adjustable, repeatable pressure source, which the HD4000 provides.

The HD4000’s nozzle spread is genuinely useful for real jobs. Flat-fan tips are a go-to for broadcast herbicides on turf. Cone and mist tips are handy for foliage and ornamental pests. The brass adjustable tip lets you move from a tight stream for cracks to a wider pattern for foundation work. If you ever want to graduate to pro grade patterns, Petra’s ProKit adds a TeeJet adapter and an XR TeeJet nozzle, so you can match label-recommended droplet sizes more precisely.

Comfort and up-time set this unit apart for homeowner and light pro routes. Padded straps and a back pad spread the load, and the extendable wand gives extra reach without overextending your shoulder. The published runtime varies by source. The HD4000 product page calls out 6 to 8 hours and 200 plus gallons per charge, while the current user manual lists a 12V 8Ah battery with about 3 to 4 hours of use and roughly 8 hours for a full recharge. In practice, the difference usually comes down to the pressure you dial in, the nozzle you choose, and whether you run the pump continuously. I advise planning your route based on the conservative figure, then enjoy the bonus time if your setup runs longer.

Product Specifications

Category	Details
Tank capacity	4 gallon translucent tank with molded volume markers, easy to see mix levels at a glance.
Pressure range	Adjustable using the silver knob, commonly listed as about 40 to 90 PSI on Petra’s product pages, and up to 70 PSI on several retailer listings. I advise planning around a 40 to 70 PSI working window, then only going higher for tasks.
Battery	12-volt, 8 amp-hour sealed lead-acid battery, user-replaceable.
Runtime per charge	Marketing claims highlight up to 6 to 8 hours and more than 200 gallons pumped per charge. The current user manual for the HD4000 family lists typical usage time of about 3 to 4 hours. I plan routes using the conservative figure.
Charge time	About 8 hours to full using the included AC charger.
Hose	High-pressure hose, about 4 feet long on the standard backpack kit. Longer 10-foot hoses are available as Petra parts.
Wand	Heavy-duty wand included, with many kits shipping an extendable wand that reaches roughly 34.5 inches. Replacement stainless wands are available if you prefer metal hardware.
Included nozzles	Six PetraFlow nozzles: shower head, two-in-one mist-to-stream, double-mist, single-mist, fan-flat, and brass adjustable. These cover everything from foliar misting to a targeted stream.
Dimensions	Retailer listings show the backpack around 9.2 inches wide and 20.8 inches tall in one listing, and 11.8 inches wide by 22.2 inches tall in another. Bundles vary, so expect roughly 9 to 12 inches wide and about 21 to 22 inches tall.
Weight	Empty weight is often listed around 16 to 18 pounds depending on bundle and retailer.
Wide-mouth lid and filter	Large opening with a mesh screen that strains debris before it ever reaches the pump. This reduces clogs and extends pump life.
Status lights	Front lights indicate power and charge status, handy for quick checks in the field.
Warranty	One-year limited warranty from PetraTools.
Replacement parts	Petra stocks the battery, charger, hoses, wands, nozzles, and even fuses, which keeps downtime short.
Typical uses	Perimeter insecticides, turf herbicides, fungicides, foliar feeds, cleaning or sanitizing tasks, and general garden spraying.
Coverage per tank	Coverage depends on your calibration, nozzle, pressure, and walking speed. Many turf labels target around 1 gallon per 1,000 square feet, so a 4 gallon tank often covers about 4,000 square feet at that setting.
Safety and PPE	Follow the pesticide label. As a baseline, EPA and university extensions recommend long sleeves, long pants, closed-toe shoes with socks, chemical-resistant gloves, and protective eyewear, especially when mixing concentrates.

 

How to Use and Install the HD4000

Before you start, set yourself up for a safe, accurate spray

Read the pesticide label from start to finish, then lay out your personal protective equipment. As a baseline, EPA guidance for pesticide handlers calls for protective clothing that matches the label, along with clear steps for cleaning and maintaining PPE. I advise long sleeves, long pants, closed-toe shoes, chemical-resistant gloves, and eye protection for mixing and spraying. Keep children and pets well away from the work area.

Unbox, assemble, and charge the sprayer the right way

Out of the box, thread the valve handle onto the hose, thread the wand onto the handle, then choose a nozzle for your first job. PetraTools’ HD4000 support page walks through assembly, initial charge, and the control layout. Charge the unit until the charger light turns green, then disconnect. The front lights let you confirm power and charge status at a glance.

If you are new to a battery powered backpack sprayer, begin every session with a full charge. Sealed lead-acid batteries prefer storage and maintenance charging, not deep discharge. Manufacturer and technical references note that these batteries should be stored fully charged and topped up periodically in storage. A practical rule, recharge every three to six months if the sprayer sits idle, and avoid storing it empty. Cooler storage slows self-discharge.

Prime the pump so flow is smooth and instant

If a new unit runs but does not move liquid, it is usually an airlock. PetraTools recommends priming with one gallon of water and a teaspoon or two of dish soap, running the pump for a few minutes, and gently tapping the base to dislodge bubbles, or using a garden hose to help push water through. Once primed, squeeze the handle and confirm a steady pattern.

Calibrate output with the simple 1/128th-acre method

Calibration answers two questions: how many gallons per thousand square feet you apply, and how much product goes in each 4 gallon fill. The 1/128th method is fast and uses water only. Mark an 18.5 by 18.5 foot square, spray it at your normal walking speed and pressure, time the pass, then spray into a measuring jug for that same time. The ounces you collect equal your sprayer’s gallons per acre. Once you know GPA, your product label rates convert cleanly to ounces per tank.

Do the setup work on clean pavement first. Calibrate with water, confirm even coverage and no dripping, then repeat the timing two or three times for a good average. University guides consistently stress calibrating with water, inspecting nozzles, and working at steady pressure for repeatable results.

Mix safely, in the correct order, and proof-test compatibility

When you are ready to mix, follow each product label. If you combine products, use a jar test first to check compatibility. Extension and industry references describe WALES or DALES style sequences that start with water and conditioners, then dry materials, then liquids, then emulsifiable concentrates, and finally surfactants and adjuvants. Fill the HD4000’s tank part way with clean water, start agitation by briefly pulsing the trigger back to the tank, add products one at a time in the proper order, then top off to volume. If anything gels, clumps, or heats up in the jar test, do not combine those products in the tank.

Choose a nozzle and pressure that match the job

Flat-fan nozzles are the workhorse for broadcast turf herbicides and banding along edges. Cone and mist tips are better for foliage and ornamentals where canopy coverage matters. Higher pressure creates finer droplets that can improve coverage, yet it also increases drift risk, so set only as high as the job requires and re-calibrate if you change pressure.

Spray technique that looks professional and controls drift

Work when wind is a gentle, steady breeze that moves away from sensitive areas. Many university drift bulletins advise aiming for roughly three to ten miles per hour, avoiding dead-calm conditions that can signal a temperature inversion, and avoiding high winds. Keep a steady walking pace, overlap your passes evenly, and maintain a consistent nozzle height. If wind shifts toward a sensitive area, leave a buffer and return later.

After you finish, clean the system so tomorrow’s spray is not contaminated

Cleanout protects your plants and your equipment. Drain the tank, then triple rinse the tank and plumbing, running each rinsate into the sprayer and spraying it out on a labeled site. Extension and stewardship programs recommend triple rinse or pressure-rinse procedures, and research bulletins show that residues left in a sprayer can injure non-target plants weeks later. Use a tank cleaner if the label calls for it, especially after tough chemistries, then run a final water rinse.

Clean the nozzle and strainer gently. Use a soft brush or nozzle cleaning tool, not pins or wire that can change the pattern and flow. Inspect the spray pattern next time you set up, and replace any tip that will not clean up properly.

Handle rinsate and empty containers correctly

Rinsate is not waste water, it is part of your spray. EPA label guidance and multiple extension programs direct users to add rinsate back into the tank for application on a labeled site, or to hold it for the next compatible mix if allowed by the label. Triple-rinsed containers can usually go to solid waste as non-hazardous, subject to local rules, but always follow the label and local disposal requirements.

Store the sprayer and battery for a long service life

Run clean water through the system, relieve pressure, and leave the tank and hose drained. Store the HD4000 indoors, upright, and dry. For the sealed lead-acid battery, store it fully charged and recharge periodically in storage. Technical references suggest topping up every few months in typical room temperatures, and never storing fully discharged. Cooler storage slows self-discharge.

Common Issues

If the unit will not spray, work through Petra’s sequence. Confirm the rocker switch and pressure knob are off before charging, verify the front lights, inspect and replace the fuse if blown, and check that the battery is actually taking a charge. Petra shows how to bypass the battery with the charger to diagnose battery versus pump issues, and how to inspect connections behind the rear access door. Most no-spray issues are a priming problem, a clogged nozzle, or a simple fuse.

FAQs for the PetraTools HD4000 Battery Powered Backpack Sprayer

How long does the HD4000 battery really last per charge?

PetraTools lists a spray time of about six to eight hours on a full charge, and their product pages and retailer listings also note roughly two hundred gallons pumped per charge. Real-world runtime varies with pressure setting, nozzle choice, and how often you start and stop.

What is the actual pressure range?

Current PetraTools pages specify adjustable pressure from about forty to ninety PSI. Some older manuals and retailer copies list a single figure near seventy PSI. The difference comes down to revisions and how the spec was reported. In practice, you set output with the silver knob and pick a nozzle to match your job.

How far can it spray if I need reach?

The unit can project a stream up to roughly twenty five feet with the right tip and setting. Distance depends on the nozzle you use, your pressure setting, and wind.

Can I use TeeJet nozzles on the HD4000?

Yes. PetraTools sells a TeeJet adapter specifically listed as compatible with the HD4000, and the HD4000 product page highlights a ProKit upgrade that includes an XR TeeJet tip.

Does the HD4000 include six nozzles, and what do they do?

The standard HD4000 kit comes with six application nozzles for patterns ranging from fine mist to fan to shower. PetraTools’ support guide explains each nozzle’s best use, so you can match the pattern to herbicides, foliar feeds, or ornamental spraying.

Is bleach or strong acid safe to run through this sprayer?

PetraTools advises against bleach because it can damage internal parts. If you must spray harsh solutions, PetraTools offers a separate acid or bleach compatible wand, but the general guidance for the HD4000 is to avoid bleach. Always follow chemical labels and equipment guidance.

What kind of battery is inside, and can I replace it myself?

The HD4000 uses a sealed lead acid battery rated at 12 volts and 8 amp hours. PetraTools sells a direct replacement and provides step by step instructions for swapping the battery through the rear access door. It is a straightforward job with basic hand tools.

How should I store and maintain the battery for best life?

For sealed lead acid batteries, reputable battery references recommend storing fully charged, keeping them cool and dry, and topping them up periodically during storage. Typical advice is to recharge every few months at room temperature so the battery does not sit partially discharged.

Does the HD4000 have a pressure gauge?

The HD4000 uses a variable pressure knob rather than a built in gauge. You set output by turning the knob and confirming pattern with your chosen nozzle.

What if my new sprayer runs but will not spray liquid?

That is usually an air lock on a new or recently serviced unit. PetraTools’ priming guide recommends running one to two teaspoons of dish soap in a gallon or two of warm water for several minutes, or forcing water to the pump intake with a garden hose. Both methods purge trapped air and get the pump moving solution.

How do I troubleshoot if the unit suddenly will not turn on?

Confirm the red rocker switch and silver pressure knob are off when charging, check the front status lights, inspect and replace the fuse if needed, and verify that the charger shows a red light when actively charging.

Can I add a longer hose or different wand later?

Yes. PetraTools lists high pressure replacement hoses in ten and twenty foot lengths compatible with the HD4000, as well as alternate wands.

Is there a cart version if I prefer not to carry the tank?

Yes. PetraTools sells an HD4000 with Cart package that uses the same core sprayer mounted on a wheeled frame.

What comes in the box?

A four gallon translucent tank with wide mouth and mesh strainer, the battery and charger, an HD wand and valve handle, and six nozzles.

How long should I charge it the first time, and in general?

A full charge takes roughly six to eight hours with the included automatic charger. A green indicator on the charger confirms full. If the sprayer will sit unused, charge it before storage and top up periodically.

How big an area can I cover on one tank?

Coverage depends on your calibrated application rate. The 1 over 128th acre method is a quick way to determine gallons per thousand square feet based on your walking speed, pressure setting, and nozzle. Once you know that number, you can calculate square footage per four gallon fill precisely.

Does the HD4000 leak or drip around the cap or fittings?

User reports in lawn care communities often cite the HD4000 as a dependable mid priced sprayer when assembled correctly and kept clean. Still, always check the lid gasket, strainer basket seating, and hose connections after assembly and after cleaning.

Where can I find replacement parts like fuses and filters?

PetraTools stocks fuses, chargers, hoses, wands, lid strainers, and the TeeJet adapter. Keeping a spare fuse and lid filter on hand is inexpensive insurance during the busy season.

Can I leave product in the tank overnight?

The safest practice is to empty and rinse the tank, hose, and nozzle after each job. PetraTools’ cleaning guide recommends a quick triple rinse routine with warm soapy water, then a final clean water flush. This prevents cross contamination and keeps valves and nozzles from sticking.

Conclusion

If you want a battery powered backpack sprayer that trades constant pumping for constant results, the PetraTools HD4000 earns its place on your back. The core strengths are real, not marketing fluff. You get long, repeatable runtime that Petra publishes at up to eight hours on its product page, with multiple retailer listings echoing six to eight hours and more than two hundred gallons per charge. You also get a practical pressure window that spans light foliar work to longer reach applications, supported by Petra’s own 40 to 90 PSI language on the HD4000 line.

Comfort and control are handled with double padded straps, a back pad, and six included nozzles so you can choose a fine mist, a fan for turf, or a tight stream for cracks. These details are spelled out across Petra’s product and retailer pages, and they are exactly what cuts fatigue and improves coverage for real world pest control and lawn care.