Read the manual thoroughly and understand all of the instructions, cautions, and warnings before using this equipment. If any section of the manual is not understood, contact your nearest authorized dealer, or contact Generac Customer Service at 1-888-436-3722 (1-888-GENERAC), or www.generac.com with any questions or concerns. 

Water supply considerations

Using the correct water supply is essential for the safe and efficient operation of your Generac pressure washer. This article provides important specifications and preparation steps to help you avoid damage to the unit, helps ensure proper performance, and maintain warranty coverage. By understanding flow rate, pressure, and connection requirements, you can prevent common issues and extend the life of your equipment. 

Environment

This article applies to pressure washers.

Water supply specifications

• The water temperature must be less than 100⁰ F.

• The water supply hose length must NOT exceed 50 feet.

• Water must be greater than 3.8 gallons per minute and no less than 30 PSI.

Preparing the water supply

• Let the water run for 30 seconds prior to connection to eliminate debris.

• Do NOT siphon standing water for the water supply.

• Do NOT use a one-way valve, vacuum breaker, or check valve in any part of the water supply.

 After connecting the water supply

• After turning on the water supply, squeeze the trigger to purge the pump system of air.

• NEVER run the pressure washer without a sufficient water supply connected and turned ON.

Not recommended water supply types

• Generac does not recommend using rain collection barrels, retention ponds, or water pumps as a water source for your pressure washer, regardless of whether they can supply adequate water pressure or not.

 

How to determine if your faucet has adequate flow rate and water pressure
 

Definitions

Flow Rate: This is the volume of water that passes through the faucet expressed in gallons per minute (GPM). It indicates how quickly water is delivered. 
Pressure: This is the force at which water is delivered, measured in pounds per square inch (PSI). It reflects how forcefully water exits the faucet. 
 

Typical outdoor faucet specifications

Flow Rate: Outdoor faucets generally offer a flow rate between 4 to 5 GPM. 
Pressure: The pressure usually ranges from 40 to 60 PSI. 

These specifications typically meet the requirements for various outdoor needs, including the operation of pressure washers. 
 

Checking flow rate and pressure

If you need to confirm that your outdoor faucet meets the necessary pressure washer specifications, follow these steps: 

1. Check flow rate

Materials needed: Bucket (with a known volume, i.e. 5-gallon bucket) and stopwatch or timer. 

Procedure 
1. Fill the bucket with your faucet at full capacity. 
2. Time how long it takes to fill the buck to the brim. 
3. Calculate the flow rate using the formula.

 

2. Check pressure 

Materials needed: pressure gauge

Procedure
1. Attach the pressure gauge to your faucet.
2. Turn the faucet fully open and read the pressure on the gauge.

Note: Follow the pressure gauge's manufacturer guidelines.

Note: It is important to follow the guidelines provided in the owner's manual to help ensure safety and compatibility with the pressure washer and its components. Additionally, it is advisable to check the water supply before and after use to ensure no issues arise.