HP Rinse or Low Pressure Rinse

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chefwong

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For like forever, after a HP rinse, mechanical wash, I always prefer to rinse via the garden hose- tap pressure.

I was not in the mood to pull out the GH for the low pressure rinse out of it's reel so I did a HP rinse as part of the car wash process.
It's been a long time since I've done a HP rinse as part of my wash routine. My main impressions was that it took more effort to wash away the soap and there was less water flushing off the paint.

I was pleasantly surprised today doing a HP rinse. Panels seemed to rinse well, without chasing leftover soap.
And or maybe it's because car paint looks so hideous in winter, it was just a welcomed experience getting the chance to squeeze a wash in on a -warm enough day-

So for those who use a PW for most if not all your cleaning. Do you prefer a HP rinse or low pressure rinse.
 
When I pursued high flow pressure washers in 2020 and 2023, I haven't rinsed with a garden hose since. So, I always rinse with the pressure washer.

My first pressure washer was an entry level Karcher, the flow rate was so lean that I actually preferred to use a garden hose as it was quicker and more effective. I actually think you waste more time setting up and using a low-flow pressure washer rather just grabbing a garden hose. Thing is, most entry to mid-level pressure washers prioritize headline pressure ratings on the box over water flow, which makes them practically useless for detailing.

While high end machines have been able to flow well, for some the cost is prohibitive. We are only now seeing pressure washer manufacturers creating detailing-specific high-flow, low-pressure machines. The Active was the first on the low end, but the likes of Big Boi and Max Flow have started to introduce detailing pressure washers. Now AR have done the same, to the point where it's flowing so well that a foam cannon can't keep up.
I often here of people who can't see the point in setting up a pressure washers because a garden hose is quicker and easier. And for a long time, I fully understood that. But that mentality is mostly from using the wrong or poorly setup pressure washer.
 
You had me thinking on which PW I was using at the time ....when I decided to make my conclusive decision to use the hose as such vs. the PW wand. And it's the same output of what I was using yesterday, which is 2GPM.

I dunno. Maybe it was also due to the fact I topped the paint 2 weeks ago : LSP experience.


I literally have dragged the hose out as part of washing even in the dead of winter.........just to rinse the cars....as my conclusive belief was that low pressure rinse was the better of the 2.
I know it's technically a new year, but I do think I have discovered a new way to wash 😁
 
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I only rinse with a hose. In fact, I almost exclusively wash with a hose too. I bought a pressure washer for the main purpose of washing the car, but have after doing it a few times went back to the hose and the pressure washer mostly does household work. I will use it for the first post-winter wash, but that's about it.

I have no shade in my wash area and live somewhere the wind is almost always blowing, even a light breeze. With a pressure washer I found I'd get misty overspray all over the car due to the wind and I always had lots of water spot issues. Since I use coatings on all our vehicles, I've found a flood rinse allows me to target the rinse area and keep overspray to a bare minimum and drastically reduce water spotting. The sheeting action with a flood rinse leaves most panels almost totally dry, so there is far less drying to do overall too.
 
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I have an electric pressure washer but rarely use it. A couple years ago I was at a crossroads as to an upgrade. Was considering a wall mounted unit with a reel.
Kept tossing my options around and ended up with a complete Eley hose system for about the same cost as the pressure washer wall unit. What swayed me in the Eley direction was the fact that one needs a hose regardless of whether they have a pressure washer or not.
Eley makes possibly the best residential hose system on the planet. I ran a dedicated one inch PEX line to the garage shut off. With the cleaning tip installed the Eley is not far behind a pressure washer. The watering tip has several options and puts out a ton of flow. To be honest I haven't used the portable pressure washer once since getting the Eley system.
 
PSA since we're discussing HP washers. Don't forget to change the pump oil on it's scheduled time

I'm very mindful of oils in the cars. For stuff like OPE, I'm not as mindful @ times
I went almost 9 months on my vacuum pump before I changed the oil. . I only realized I went that far long when I removed the cover to get to the fill port in which I had labeled it . It's now labeled on the outside of the cover on when the last OCI is
 
Setec Astronomy said:
Vacuum pump?
Click to expand...
I have a chamber vac food sealer....the vac pump in that I kinda say I aim to change it out every 3 months, irrevalent of usage cycles (which is way lower than max before recommend OCI).
 
HP rinse for any pre-wash or decon wash and for after a contact wash I switch out tips to one that drops me to 100psi for the final rinse
 
What is the net result of upsizing a tip, just short less pressure ?
Why not just use the unloader
 
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chefwong said:
What is the net result of upsizing a tip, just short less pressure ?
Why not just use the unloader
Click to expand...
You gain flow which makes rinsing easier and the drop in pressure produces less mist. Some pressure washers respond better to upsizing than others.
 
SNP209 said:
You gain flow which makes rinsing easier and the drop in pressure produces less mist. Some pressure washers respond better to upsizing than others.
Click to expand...

Time to order a new tip.....this reads like one can achieve a HP wash and a HP-Mid Pressure (rinse) off a single HP hose setup
No need for the tap hose...
 
chefwong said:
What is the net result of upsizing a tip, just short less pressure ?
Why not just use the unloader
Click to expand...
SNP209 is correct, but I don't really gain much extra flow. I run a custom unit that I built using a 4hp 220V motor with an AR RC series pump that gives me 3.4gpm at 1600psi with a 5.5 nozzle. For rinsing cars off I run a 6.0 nozzle that gives me 1200psi and final rinse is a with a 20.0 nozzle that gets me to 100psi. I tried one of those shower nozzles and it left to much foam in cracks and crevices. 100psi was the sweet spot between reducing fine mist and removing and foam left from the contact wash.
 
chefwong said:
What is the net result of upsizing a tip, just short less pressure ?
Why not just use the unloader
Click to expand...

Never, ever mess with the unloader to adjust pressure, leave it full open. They are calibrated to work at fully open, you will otherwise generate more heat and stress the motor and pump. Alway adjust pressure via the nozzle tip orifice.

The bigger the nozzle orifice, the more flow it will generate at a lower the pressure. Having said that, you still need some resistance to allow the pump to work efficiently. Thing is, going too big won't damage the machine, but going too small will as it will cause the motor to labour, increase the amp draw and therefore generate more heat.

Each pressure washer needs to be treated differently when it comes to nozzle size. What works in an Active 2.0 may not work well in a Karcher K5, a Kranzle to an AR. Also, nozzle orifice size is different to nozzle angle size. You will get some minor added pressure by using a 25-deg angle compared to a 40-deg, but to the effect most people assume. Nozzle angles will be denoted with whole numbers, as in 15-deg/25-deg/40-deg. Orifice sizes are denoted with either a number beginning with a 0 (030, 040, 050 ect), or 0.0 (3.0, 5.0, 6.0 ect). Below is a basic chart, but again, you may get some variance depending on machine. Notice how small the increments are, its a fine line between great flow and workable pressure, a high pressure/low flow setup that risks damaging the machine, and a unit that loses its effectiveness by flowing too much.



I think this is where some don't find value in a pressure washer for car detailing. Simply put, they buy a machine off the shelf, use it a few times and find the experience underwhelming. 99% of the pressure washers sold in box stores or Amazon are made to clean patios and other outdoor cleaning duties. So, they produce lots of pressure, hence the misting, but don't actually produce meaningful and useful flow.

Make a few nozzle/hose/gun modifications and that makes a big difference in how effective a basic machine can be.

(Please know I'm not calling anyone out here, just passing on what I've learnt over the last few years and perhaps saving someone from buying the wrong machine. That's because I wasn't happy with the basic pressure washer I had purposely bought for cleaning my cars, but came away underwhelmed. Buy once, cry one and then be happy.)
 
Whether I rinse with a hose or pressure washer, I always do a slow rinse to help sheet off water. I just got an old hose and cut off the to get a smooth laminar flow. I use quick connects to switch.
 
SNP209 said:
You gain flow which makes rinsing easier and the drop in pressure produces less mist. Some pressure washers respond better to upsizing than others.
Click to expand...


Tried the Super Size Tip. Way less pressure but same flow..just less PSI. Nothing gained, nothing lost. Pump just outputting what it's rated output is

This is semi new and foreign as per the OP, I have dragged the hose out as well always....to do a final High Volume, Low Pressure Rinse.
Off to test more with the super low PSI off the HP hose
 
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chefwong said:
Tried the Super Size Tip. Way less pressure but same flow..just less PSI. Nothing gained, nothing lost. Pump just outputting what it's rated output is

This is semi new and foreign as per the OP, I have dragged the hose out as well always....to do a final High Volume, Low Pressure Rinse.
Off to test more with the super low PSI off the HP hose
Click to expand...
Which model is your PW and what size nozzle did you try out?
 
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