Frequently Asked Questions

Does the unit come with a battery?
Yes, if you order the basic unit or the unit with the Lithium Ion upgrade

Does the unit come with its own charger?
Yes, if you  order the basic unit or the unit with the Lithium Ion upgrade

Can the pistol grip be used with the wand?
Yes, we provide adapters that enable this usage

How long does the battery last on a full charge?
The battery should last 4-5 hours on a full charge.

What is the spray distance?
When using the right nozzles our backpack can spray up to 35ft.

Will what I want to spray work with your backpack?
Our backpack is extremely durable. We have customers who use our backpack for spraying a wide variety of solutions. From paint to concrete sealant to 50% bleach solutions our unit can handle almost anything.

Can I use nozzles from other companies with your backpack?
We are currently working on a system for adapting different nozzles with our backpack. Currently we have one working adapter that allows T-jet nozzles to be used with our backpacks. Please contact Paige for more information (707-331-0971)

How do I clean your unit when swapping chemicals?
Run at least a gallon of water through the unit to make sure it is clean.

My backpack is making noise and the lights are all on but there is no pressure and when i pull the trigger nothing happens.

your backpack is having trouble priming. The easiest way to fix this is to fill the tank full with around 4 gallons turn the backpack on and then give the backpack a good shake to try and get the backpack to prime. 

I think there is something wrong with my pump or battery what should I do?

The pump and battery are the most durable parts of our backpack sprayer. If there is an issue it is unlikely that your battery or pump has any issues. There could be any number of issues with the backpack sprayer from the handle to the nozzle or something could just be blocked. First remove the hose from the unit and then try running it. Be warned that if everything is working it will spray out of the hole so be ready to shut it off. If it does spray out the hole then start adding parts to the backpack until you can find the problem.

How long will it take for my backpack to get to me?

The free shipping that is included with the backpack is UPS 3-5 day ground and we ship out of northern California. Depending on your location it could take 3-5 days 

M4 Troubleshooting Guide
ISSUE Root Cause Solution
Pump Runs Continuously with Full Tank and Valve Off Pump Diaphragm is Not Priming Prime Pump by spraying garden hose into the tank fine filter inlet while the unit is on.
Intermittent Power Bad Battery Connection or Bad Red Piston in Trigger Verify it is an electrical problem by lightly tapping unit on table while on. If voltmeter lights flicker, electrical issue is confirmed. Tighten Battery Spring Plate Screws, Bend J2's up and Spring Plates Down, Check for Loose Wires/Bad Bundle Connections, Make sure the bottom plate is screwed in tightly, Replace Plastic Valve Trigger Handle Red Piston
Battery Not Charging (Charger Light Stays Green/Amber when plugged into base) No Battery Connection Verify by unplugging AC (leave charger plugged into base) If no light on charger, bad battery connection confirmed. Tighten Battery Spring Plate Screws, Bend J2's up and Spring Plates Down, Check for Loose Wires/Bad Bundle Connections
No Power, No Voltmeter Lights This can be caused by multiple electrical issues, but usually just one.  In order of likelihood the causes are : 1) j2 battery connection to battery plate, 2) battery plate to wire connection(loose screw - this also causes intermittent power), 3) red (+), black (-), or blue (switch ground) wire bundle connection, 4) rotary switch blown (normally accomapnied by blown fuse), 5) fuse blown, 6) low battery, 7)bad pump, 8) bad red switch Before diving into the following tests to further isolate the root cause(s), you can choose to call 707 478 2162 and we can walk you through it in 5-10 minutes, or you can address/repair all without anaylsis: Verify/secure/replace all of the battery connections, wire bundles, and internal/external fuses; Perform a voltage check on the battery using the installed voltmeter or handheld digital voltmeter (VDC > 12.4 after full charge cycle of 8 hours); Directly connect pump +- wires to the battery; and re-wire the switches to be parallel so that they both turn on the pump directly. If you prefer to find root cause,  do the following:                                                                                                                      1) Connect the charger to the M4 charger panel (base only-do not connect the AC plug into 110 vac) and observe charger LED. If light is not illuminated, the battery is not connected and root cause items 1-3 and 6 (battery continuity, wire terminal bundles, and battery power) need to be checked. (Conversely,  if LED is illuminated, the battery is connected. )                                                                                                                                                    2) Leaving the charger plugged into the base, now connect the AC plug side of the charger into an AC 110V wall outlet and turn on the unit using only the rotary switch, slowly rotating clockwise. If none of the voltmeter lights on the base illuminate and the pump does not activate, items 4,5,7, and 8 need to be checked (rotary, fuse, pump, red switch). (Conversely, if voltmeter or pump power up, all components are confirmed working except 1-3 and 6, battery continuity, wire bundles and battery)                                   3) To eliminate 6 and 7 (the battery and pump) as the cause, connect the pump +- wires directly to the battery. If the pump stirs, both the battery and the pump are good. If this occurs, the most likely culprit is the rotary switch, and it must be assumed that the fuse is also blown. The rotary switch can be verified by directly connecting both switches to the pump (parallel). If the red (toggle switch) turns on the pump and voltmeter, but the rotary does not, the silver rotary switch is the root cause. If the rotary turns on the unit and the red does not, the red switch is the culprit. Apologies if this is confusing. Feel free to call 707 478 2162 and we can get you back up and running in a few minutes.
No Power, But Voltmeter Lights On Back pressure on Pump (hose, valve, wand, nozzle blockage), Possible Operator Error (forgot to pull trigger to activate pump), Bad Pump If removing hose (relieving back pressure) is not the solution, perform the Battery to Pump Direct Test for pump verification. If removing the hose from the end of the pump results in pump activation, verify the user understands the M4 pump is on demand (operator error), or test for blockages by progressively removing the nozzle, wand, and valve. Replace Valve O ring piston if traced to valve.
Plugged 110 VAC into charger port instead of 12 Vdc from factory charger Original charger lost, AC chord assumed to work Trace all burned wires to components, replace components
Red Flashing Charge Light, Voltage <12.3 after charging, Battery provides less than 1 hour run time, Battery has been depleted to far below 12 volts (left on) Bad Battery Replace Battery
Pump "Burping" frequently (<1hz) when Valve is closed Slow Leak between pump output and nozzle; Valve Trigger Red Piston has damaged/dislodged O ring, Allowing small continuous flow Verify all connections have one good washer and tighten; Replace Valve Trigger Red Oring Piston
Pump Output Threads Sheared Off by hose Pump Neck Broken Replace Pump
Tank Collapses as fluid level drops Lid Vent is not allowing air into the tank Remove Vent, Clean out vent holes, Replace Lid or lid vent with new design
Shoulder Strap Anchor screw dislodged Screw was installed incorrectly Re-install screw with plastic hook engaged to prevent pull out load
Pump oozes fluid when tank full (and power off), low pressure output( power on), pump fatigue life reached Pump diaphragm is perforated/damaged Replace Pump
Low Flow/No Flow Rotary set at low flow, blockages in nozzle, wand, hose, valve, pump inlet/outlet Turn up rotary; Remove one at a time and observe when flow is restored: nozzle, wand, valve, hose. Locate and remove blockage. If valve is the issue, replace the red oring piston
High flow/leakage when valve trigger is off O ring is damaged or out of place, allowing flow Replace valve trigger red piston o ring
Leaks occur only when pump is running Pump head/seal has been damaged, possibly by extreme concentration, PH or chemical reactivity Replace Pump
Leaks occur slowly over time from the base Seal between tank nipple and pump intake elbow is compromised. Tighten hose clamps, sand down smooth the nipple parting line, replace the hard thermoplastic elbow with the new soft viton elbow.
Rotary Switch Does Not Change Flow Rate Red on/off needs to be off in order to use the rotary silver switch.  Turn off Red Toggle Switch while using the Silver Rotary variable flow switch. Both switches turn on the pump with the newest wiring configuration (parallel)
Unable to turn off power Both Red (Toggle) and Silver (Rotary) Switches Need to be turned off to turn off power. If either is left on, unit stays on. This is true for parallel wired systems produced beginning in 2019. For earlier versions both switches are required to turn on the unit and only one switch is required to turn off the system. However it is a good practice to turn off both switches, and verify by observing the voltmeter lights are off when charging or storing the M4. Turn off both switches during charge cycle or when not using the M4


Nozzle Flow Chart