What’s in the box?

Accessory Bag



Metal Pole

Unit (Pre-assembled)

What are the parts of the HD4100?

The HD4100 has a lot of different parts that combine to make it the great tool that it is.


4-Gallon container that holds the liquid solution. It has a wide-mouth lid for easy filling and a translucent design for easy monitoring of the solution level.

Cart Handle

Located at the top of the sprayer and is used for carrying the sprayer or pulling it behind on the cart. It is designed for comfortable grip and ease of use.


PetraFlow Nozzles are a set of high-quality nozzles that are designed to provide a wide range of coverage and deliver a consistent spray pattern.


A 12-volt, 8 Amp hour sealed lead-acid battery that provides 6-8 hours of continuous use on a single charge.

Ergonomic Straps

The adjustable padded side strap for easy carrying and an ergonomic handle.

Valve Handle

The mechanism that activates the pump and starts the spray. Sturdy, lightweight handle.


The wheels are designed to be durable and make it easy to move the sprayer around.

How to use the HD4100?

Learn how to effortlessly operate the HD4100 with our easy-to-follow user guide.

Step 1

If fully charged, the LED voltmeter will be pointed to the green zone. If the battery requires charging, you will see the red light indicating a low charge. Charge fully by plugging into the 110V outlet and allow the battery to charge 6-8 hours. If the voltmeter is not operating upon arrival, fill the tank with water and run the unit for at least 30 minutes to activate.

Step 2

Pull the sprayer to your destination area. Your sprayer is easily carried or mounted on your back.

Step 3

Connect the valve handle to the hose and the other end to the wand.

Step 4

Take the base of the wand and screw it into the handle and make sure washer seal is on the wand.

Step 5

Attach your nozzle directly to the end of the wand or to the adapter piece.

Step 6

Turn on your sprayer using the red power switch or by using the silver pressure adjuster while the red switch is OFF.

Step 7

After spraying, turn both the red switch and the silver adjuster OFF to preserve battery life.

Step 8

Empty any remaining solution and flush it with clean water.

Step 9

Store the sprayer in a cool, dry place.

Troubleshooting your HD4100 Battery-Powered Backpack Sprayer

Don't let a malfunctioning sprayer keep you from your gardening chores - use our troubleshooting guide to fix common problems with the HD4100 battery powered backpack sprayer.

Check tank

To do this, try plugging the charger into the unit. If the unit is charging, the charger light will turn red. When doing so, make sure that you are plugging the charger into a working outlet.

Check battery

Plug the charger firmly into the battery charger port on the base of the unit, then plug into a 110v outlet. Your battery will last many years but may need to be replaced eventually.

Inspect nozzle

If the spray is not coming out of the nozzle or the spray pattern is not as expected, inspect the nozzle for blockages or damage. Unscrew the nozzle and clean it thoroughly with water to remove any dirt or debris. If the nozzle is damaged, replace it with a new one.

Check for leaks

Check all connections to ensure they are tight and not leaking. Replace any damaged or worn parts as needed.

Check solution

Make sure the spray solution is mixed properly and not too thick. Adjust the mixture as needed to ensure proper flow and spray pattern.

How To Change your Sprayer Battery?

Your HD4100 lead acid battery uses tried-and-true technology that will give you many years of safe use. With repeated use, you may notice that your battery loses its ability to hold a charge or provides only enough power for short-term jobs. You can purchase brand-new batteries from PetraTools’ website. Here's how to remove & replace an existing battery:

Step 1

Make sure that the battery charger is not plugged into the unit.

Step 2

On unit base, at the bottom, there’s a small battery compartment door at the bottom of the unit. Unscrew the cover of the battery compartment.

Step 3

There will be a red wire & a black wire attached to the battery. You can either remove the wires at the terminal or cut the wire close to the terminal with wire cutters. Make note of which wire was attached to the + and – terminals.

Step 4

Slide the old battery out. Please recycle!

Step 5

Place the new battery with the terminals oriented the same way as the old battery. Reattach the red & black wires as they were on the old battery.

Step 6

Slide the new battery back in to the battery compartment & close the black plastic door and screw it tightly.

How To Clean your Sprayer?

Maintaining a clean HD4100 Battery-powered Backpack Sprayer will keep it in good working order. Here's how:

Step 1

Empty any remaining solution from the tank and rinse it thoroughly with clean water.

Step 2

Fill the tank with a cleaning solution, such as water and vinegar or soap and water.

Step 3

Pump the sprayer to circulate the cleaning solution through the hose and nozzle.

Step 4

Let the cleaning solution sit in the tank, hose, and nozzle for 15-20 minutes.

Step 5

Rinse the tank, hose, and nozzle with clean water and pump the sprayer to flush out any remaining residue.

Step 6

Let the sprayer air-dry, and store it in a cool, dry place.

How To Prime the Pump?

Priming your HD4100 Battery-Powered Sprayer is quite easy. Just follow these two steps:

Step 1

Add 2 gallons of warm soapy water into the tank

Make sure that you use warm water and that you are adding the right amount of soap. Ideally, you should add around 1-2 teaspoons of liquid soap.

Step 2

Close the lid and turn on the unit

Make sure that you have tightly closed the lid. Depending on what's causing the issue, you could have flow coming out of your hose within a few seconds to a few minutes.

Nozzle Support Guide

Every HD4100 comes with five versatile nozzles to help you tackle your toughest spraying jobs. Here’s what each of your new HD4100 nozzles can do:

Bendable Nozzle

Flexible enough to reach a variety of places. Twist top of the nozzle to adjust spray from a mist to long distance spray.

Orange Cone Nozzle

Volume nozzle that lets a significant amount of solution out.

Double Head Nozzle

Double Head mist nozzle that lets you cover a large area with a medium/fine mist.

Single Head Nozzle

Single Head nozzle for a very fine mist.

Flat Tip Nozzle

Single Head nozzle for a fat fan spray.


The battery on your HD4100 is designed to provide up to 2 hours of continuous spray time on a single charge. To ensure the longest battery life possible, make sure to fully charge the battery after each use and store it in a cool, dry place.

2 hours spray time

How To Prepare your Sprayer for Winter Storage?

Before you put your sprayer away for the winter, there are a few things you should do to make sure it’s in good shape for next season.

Step 1

Run 2 gallons of warm water mixed with 2 teaspoons of liquid dish soap through the unit to clean all internal parts, then run 1 more gallon of warm water only through. Spray until the unit, wand & hose are fully empty.

Step 2

You may plug your HD4100 unit in for constant battery maintenance, or if this is not possible, simply charge fully before storage.

Step 3

Place the unit right-side-up in the warmest storage possible. Do not store long-term in temps below 32°F.

Step 4

Storage in its original closed box is ideal, but if that’s not an option, you can cover it with a canvas or plastic tarp to protect it.

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