How to buy a pressure washer

What's most important: HP, PSI or GPM?

First of all, it's important to understand what each of these acronyms mean. HP stands for horsepower, PSI for pounds per square inch and GPM for gallons per minute. The HP of a pressure washer is divided up to produce bother the pressure at which the water is released (PSI) and the number of gallons that are released (GPM). For example, a 2 HP motor can produce 2.1 GPM at 1600 PSI or it can produce 3.0 GPM at 1100 PSI. Cleaning power is a function of both volume and pressure.

Size does matter.

When selecting a pressure washer, first determine the minimum PSI you need to break the bond between the dirt and the surface you are cleaning. "Units of cleaning power" can be calculated by multiplying the GPM by the PSI. (i.e., 4GPM x 1800PSI = 7,200 units of cleaning power)

After selecting a pressure washer with at least the desired PSI level, look at the GPM rate. The higher the GPM, the faster your cleaning job will be. That's because once you have the necessary pressure to remove the dirt and grime, the only way to make your job faster is to increase the rate at which water is released.

You can lower the cleaning pressure capacity of a larger washer by simply changing spray nozzles or using a variable pressure wand. You can not make a smaller washer bigger. Horsepower is horsepower; a 2 HP motor can not pump over its capacity.

Always buy a unit big enough for your needs. Buying a unit that does not have adequate cleaning power will cost you extra clean-up time and repairs in the future.

Do I want a gas or electric pressure washer?

Gasoline engines are best when you need a portable unit. Since electric motors are quiet and emit no exhaust, they are ideal for indoor use. With the Alkota trailer mount you can conveniently carry water along with you.

What's the difference between belt drive and direct drive?

The drive refers to how the pump is connected to the power source, such as a gasoline engine or an electric motor. Direct drive means that the pump is connected directly to that source, while a belt drive unit transfers energy from the power source to the pump along an intermediate belt.

Direct drive pumps are more compact and typically cost less than belt drive pumps. However, direct drive pumps are not as durable or as long lasting as belt-driven ones. The connected power source and higher RPM generate heat, shortening the life of direct-driven pumps. Excessive vibration, a problem with the direct drive, can also cause a shorter life. And with direct drive, any damage or stress on the power source also damages the pump.

With belt drive, the pump is separated from the motor, protecting the pump from added stress and heat, extending the life of the unit. Belt drive pumps also generally operate at a lower RPM, causing less heat build-up, which further protects the pump.

Should I buy a hot water or cold water pressure washer?

It always depends on what you are cleaning and how fast you want to get the job done. If you need to clean grease or oil, hot water will do a better job of breaking down the grime. Hot water can decrease cleaning time and help detergents and chemical cleaners work better. They also sanitize in areas where bacteria is a problem.

What safety features should I look for?

1. A safety relief valve on hot water units. This valve should be mounted between the pump and the coil inlet, not on the coil outlet. Valves mounted on the outlet will spray dangerous hot water in an emergency.
2. Automatic shut-off switch. This turns the heat source off if it receives an insufficient flow of water.
3. Float tank/anti-siphon device protects water sources from contamination.
4. Trigger gun increases operator safety.
5. Thermostat regulates heat.

Should I buy a portable or stationary unit?

This depends on your needs. If dirt is confined to one work area or room, a stationary unit might be the best. However, if your stationary unit is permanently installed, service and repairs can be more expensive since the technician will need to travel to your location.

A portable unit is convenient, especially if your have multiple areas to clean. Pay close attention to the tires on a portable unit. Make sure they are well lubricated and roll easily. Also make certain the unit is not top heavy; a top heavy unit can be dangerous for an operator to transport.

When I buy a pressure washer, what other equipment will I need to make my pressure washer efficient?

If you will be using your pressure washing equipment for vehicle washing you may want to install a water softener depending on water conditions. It may enhance the performance of your machine

For any pressure washer, you may want to purchase other accessories to get the most productivity out of your machine. For example, different brushes, nozzles, wands or chemicals can help meet the demands of your specific cleaning job. Hose reels can also increase safety and extend the life of the hose.

How will I need to maintain my pressure washer?

Like any equipment, your pressure washer will last longer and perform better if you take proper care of it. Citation will walk you through maintenance procedures for the pressure washer you are considering. As with all equipment, make sure you purchase a machine for which parts are readily available.