Pressure Washer Fittings 102: Applications and Usage – Obsessed Garage Support

A Deep Dive into the Obsessed Garage Approach to Fittings and QDs Application and Usage.

Any time you search the web for pressure washer fittings, you get bombarded with so many different ways to connect all of your parts and pieces. Even on Obsessed Garage, the vast number of options can get a little overwhelming. If you're having trouble sorting through the mess, this article should be exactly what you need.

Where to Start?

If you've not read it yet, check out this article first for a primer on what we're dealing with here: Pressure Washer Fittings 101: Fitting and QD Naming

Once you have our nomenclature down, we move on to actually using these parts and connecting up all of our accessories. We'll break this up by fitting and application type. If you're looking for what to use for your specific pressure washer model, check out this article: Pressure Washer Fittings 101: Pressure Washer Brands and What You Need to Adapt (link coming soon).

The main applications for fittings and QDs we'll be talking about today are in relation to the following:

Garden and Inlet Hose Connections
Pressure Washer Outlet
Pressure Washer Hoses
Pressure Washer Sprayers
Pressure Washer Wands
Pressure Washer Nozzles

Garden and Inlet Hose Connections

Garden Hoses and their respective connections are really pretty easy. These connections use 3/4" GHT threading and have a consistent orientation: outlets are always male-threaded, and inlets are always female-threaded. This consistency helps you make sure things are set up correctly since there is only one way that something can connect.

Here's an example of a setup from the hose bibb, connected all the way to a pressure washer:

Hose Bibb + 3/4" Female Garden Hose Coupler > 3/4" Male Garden Hose Plug + Inlet Hose Female End > Inlet Hose Male End + 3/4" Female Garden Hose Coupler > 3/4" Male Garden Hose Plug + Pressure Washer Female Inlet

Notice that every point where water is flowing out is male-threaded with a female-threaded coupler attached. Water is always flowing into a male-threaded plug that is attached to the female threads of the next connection point. This system will always stay consistent unless there is an unusual setup.

Sometimes, our customers find that their pressure washer has 3/4" male BSPP threads on the inlet. This is how most machines come from the factory. BUT, every machine also comes with an adapter: 3/4" female BSPP to 3/4" female GHT. This adapter fits the inlet and gets us back to the standard system that GHT connections define: male outlets and female inlets.

CR Spotless has incorrect threading on their units and defies the above system. Rather than having a 3/4" female GHT inlet, they utilize a male threaded inlet in order to match the other side of the system. Because of this, the small inlet hose that they provide is a female to female-ended hose so that you can still connect to a standard setup that has male threads on the outlet and female threads on the inlet. If you didn't have their inlet hose or wanted to use a different hose, you would simply need a 3/4" Female-to-female GHT adapter to be able to fit the male threaded end of a hose to the inlet of the CR. There are other times when you'll run into a situation like this, but they are rare.

Leaks are prevented in a garden hose scenario by the rubber washer in the female threaded end. These should always be present, and the first thing to check is if leaks appear. The use of pipe tape or sealant is not recommended as they can inhibit the firm seal of the rubber washer.

Pressure Washer Outlet

All standard pressure washers use some type of M22 male threaded outlet. 14mm is the most popular, but 15mm has become very prevalent over the last few years. To learn more about the specifics of this type of connection from a technical standpoint, see the linked article back at the top of this page.

M22 is often used as a hose connection for pressure washer outlets. The connection on the pressure washer outlet is always going to be male-threaded with an internal diameter of 14mm or 15mm. This male thread will accept the female end of an M22 hose that has female threads and an internal diameter with an o-ring. In the systems that we have seen, there is never a scenario where the connection is reversed with the female threads on the pressure washer and the male threads on the hose. This connection is a twist-on connection and can usually be hand-tightened.

At Obsessed Garage, our preference is to convert this connection into a Quick Disconnect setup. We always want the pressure washer outlet converted to be a 3/8" plug, so we have to use a fitting with an M22 female on one end and a 3/8" plug on the other. With a 3/8" coupler on the connecting hose, this is a very convenient way to connect and disconnect hoses to the outlet of a pressure washer.

Pressure Washer Hoses

Being that pressure washer hoses connect to the outlet of a pressure washer, most of you will come across an M22 female style. As you will see from the sprayer section, both ends are usually the same so that they can connect to the M22 pressure washer outlet and the M22 connection on the sprayer inlet. Another common connection type, and the one that we use as standard here at Obsessed Garage is 3/8" male NPT. There are other connection types used on some machines that fall outside the norm. One is the non-standard plug and pin style mentioned in the outlet section. Another is a smaller European-style connection that is basically a mini M22 in a 1/4" thread size. This can be found on the Comet Static 1700 or an AR630

Regardless of thread type, we always want to convert this to a QD form when we can. Unlike garden hoses that will always have a coupler on the outlet and plug on the inlet of every connection point, we like to have couplers on both sides of the hose. This means that the opposing pressure washer outlet and sprayer inlet must be a plug-style QD to connect to the coupler on each end of the hose.

QDs needed for common hose types:

3/8" Male NPT Hoses:

14mm M22 Female Hoses (Kranzle, Actiive 2.0, Greenworks, Karcher, AR Blue Commercial):

15mm M22 Female Hoses (Active VE Series, SunJoe, AR Blue Consumer, Stanley):

Brass M22 Male (15mm) to 3/8" Quick Disconnect Coupler

Pressure Washer Sprayers

Pressure washer sprayers can generally be broken up into two different categories: OEM and aftermarket. Each of these sprayers, much like every pressure washer product, has an inlet and an outlet.

Inlets:

OE sprayers are usually cheap, plasticky junk and include standard 14mm or 15mm M22 male threads. Some use the non-standard plug-and-pin style connection, like the Karcher K2-5 series, among others. The Comet Static 1700, as mentioned above, uses a 1/4 European connection for its sprayer.

For M22-style sprayers, since we use hoses with couplers on the end, you will need to convert the M22 male threads to a plug that will fit into the coupler on the hose. This is typically the same part as what is needed for the pressure washer outlet.

For standard 14mm and 15mm M22 connections, these are the QD fittings that you need for the sprayer inlet:

For sprayers that have the non-standard plug and clip style, there's nothing we can do and you should upgrade to an aftermarket sprayer if possible. For the 1/4" connection on European machines, we don't have any fittings or QDs for this.

Aftermarket sprayers almost always include a 3/8" female NPT inlet that allow for the direct connection of a 3/8" style hose or a 3/8" male NPT plug for a QD connection to the hose. Our New OG Spec Mosmatic Sprayer has an integrated 3/8" plug built into the swiveling inlet.

Here are your options for an aftermarket sprayer inlet:

Outlets:

Similarly to the inlet of OE sprayers, the outlet side is usually M22. Unlike the inlet side, however, almost all OE sprayers utilize a standard 14mm M22 connection. While the inlet is male-threaded, the outlet is female-threaded. This connection mimics the outlet of an OE M22 style hose and allows the connection of a standard pressure washer wand or lance.

Some entry-level electric pressure washers use a plastic or metal quick-lock system instead of an M22. We don't offer any fittings for this type of connection.

For M22 sprayer outlets, these are the QD fitting options that we have available:

Aftermarket sprayers like our Original Mosmatic Sprayer have 1/4" female NPT threads on the outlet. This allows the installation of a 1/4" male coupler so that we can connect spray nozzles and wands equipped with a QD plug. Our options there are the following:

Pressure Washer Wands

Pressure washer wands, just like sprayers, can generally be broken up into two different categories: OEM and aftermarket. And again, each of these wands, much like every pressure washer product, has an inlet and an outlet.

Inlets:

OE wands typically consist of a metal tube and have a threaded inlet in 14mm M22 male. Some entry-level electric pressure washers have plastic wands with a quick-lock system instead of M22.

For M22-style wands, since we use sprayers with couplers on the end, you will want to convert the M22 male threads to a plug that will fit into the coupler on the sprayer. This is typically the same part as what is needed for the pressure washer outlet and sprayer inlet. For our uses, we don't offer a fitting to bring the M22 male threads on the OE wand inlet down to a 1/4" plug to attach to an aftermarket sprayer. Rather than try to use one of these OE wands, just upgrade to something that matches your sprayer.

For standard 14mm M22 connections, these are the QD fittings that you need for the wand inlet:

*For the plastic wands that have the non-standard quick-lock system, there's nothing we have to allow for an upgrade to that connection.

Aftermarket wands almost always include a 1/4" male NPT inlet, which allows for the installation of a 1/4" female plug. This makes it super easy to connect right up to the 1/4" coupler on your aftermarket sprayer. Our New OG Spec Mosmatic wand has an integrated 1/4" plug built into the inlet. Here are your options for an aftermarket wand inlet:

Outlets:

Most pressure washer wands can connect to a typical 1/4" plug style sprayer nozzle or accessory. This means that the end of these wands includes a 1/4" coupler. While some wands may have 1/8" female NPT threads for a 1/8" male NPT semi-permanent nozzle, these are rare in the consumer space. Typically, a 1/4" coupler is the most common outlet. These couplers are usually only replaced if they fail, and are meant to be installed by manufacturers in such a way that they are not removable. So, if you have a failure, simply replace the wand.

Most aftermarket wand outlets share a similar structure. However, the Original Mosmatic Wand has an additional fitting installed on its end during the manufacturing process, which converts the outlet to 1/4" female NPT. As a result, a 1/4" male coupler can be installed or replaced. On the other hand, our OG Spec Mosmatic wand is comparable to the OE wands in that it has a coupler permanently installed on the outlet. Although it can be replaced and we do offer a M12x1mm female coupler for that purpose, it is a challenging task.

We have couplers available for both of our Mosmatic wands:

Pressure Washer Nozzles

Pressure washer nozzles are probably one of the most misunderstood things in the entire pressure washer category. Because these get pretty intense, we have an article dedicated directly to them here: Pressure Washer Fittings 103: Spray Nozzles

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