power washer-adding hot water?

[Homebrewblob]

Me and my brother clean commercial kitchen exhaust hoods and fans in addition to our usual maintenance tasks.

We use a dewalt 4000psi gas pressure washer fed from a garden hose (customers water supply). The pressure washer is bolted to the floor of a panel van, next to it is a NORTHERN TOOL diesel water heater bolted to the floor as well, there’s a 90 degree double wall elbow on top the heater to direct the exhaust out the back of the van. The max temp on the heater is 250 degrees and we run it maxed out 100% of the time.

Works GREAT never had an issue so far, the heater is very good quality.

The pressure washer feeds the heater so no issues with the pump.

We regularly run 100’ to 200’ hoses from the van out on top of restaurant roofs and inside the kitchen. even in the dead of winter Through snow, the water coming out of the wand is HOT HOT HOT.

It does take a few seconds of shooting into the sky to see the hot water show up but once warmed up she’s ready to blast.

When you let off the trigger you can hear the burner shut off, and once your back on the trigger the burner relights!

 

[Homebrewblob]

Bluechipx
What do you use your pressure washer on? Heat really makes a difference in effectiveness on grease, oil, and paint removal. Yes, the heater always goes after the pump. For the person that suggested propane fired heater, consider the size of tank you would need to match btu equivalent of diesel, and the size of tank needed to keep it from freezing up.

I have a pump/heater combo unit now, my problem is that the water coming out of faucet is so cold that it barely reaches the hot category (I don't have an exact temp) exiting the machine, its another 200' of hose till the wand at which point the water is just warm, I need one of those add on heaters mounted to the boom lift so I can get HOT water.

Add a diesel northern tool burner after your pump and that 200’ won’t matter, the wand gets hard to hold after about 30 mins of constant 225f+ water. Our hoses are rated for 250F and our guns are 285f I think.

The hoses are expensive and so is the guns.

The problems we have are O RINGS! we blow at least 1 ring a job and sometimes no ones at the van to notice.

Turns into a Sauna in there!

On bad days we’ve had to chain repair 3/4/5 o rings before we get a break.

When playing with HOT water, get the spendy stuff if possible!

Oh and Rotary tips are our best friend, don’t get the cheap ones tho!!!
The green Cry-oby tips from homedepot burn up at 4000psi REAL FAST.

 

[Homebrewblob]

Northern Tool has an add on unit that goes on the high pressure side. It works great. Uses fuel oil for the heat.
View attachment 301345

That’s the exact one we got.
3 of them!

LOVE THEM and can’t say enough good. So far so good after almost 5 years

 

[true temper]

This is what happened to my hose when the safety failed, I noticed the burner running with no flow at the wand. I took off running to trigger the wand, I was too late to get it cooled down she blew before I got there. I was very lucky I was on the run or I would have gotten burned real bad. I installed 2 new safety’s switches after that.

Sent from my iPad using Tapatalk

 

[Bluechipx]

Bluechipx
What do you use your pressure washer on? Heat really makes a difference in effectiveness on grease, oil, and paint removal. Yes, the heater always goes after the pump. For the person that suggested propane fired heater, consider the size of tank you would need to match btu equivalent of diesel, and the size of tank needed to keep it from freezing up.

I have a pump/heater combo unit now, my problem is that the water coming out of faucet is so cold that it barely reaches the hot category (I don't have an exact temp) exiting the machine, its another 200' of hose till the wand at which point the water is just warm, I need one of those add on heaters mounted to the boom lift so I can get HOT water.

I really don't use the pressure washer much BUT I like extremes in everthing I do so I am attracted to the hot water option. Everytime I buy some new whatever it is like Christmas morning for a ten year old when the delivery truck pulls in my driveway! Carefully taking it out of the box, inspecting all the parts that came with it, throwing the instructions in the garbage, humbly getting the instructions back out of the garbage without my wife seeing me and finally playing with it before retiring it to a back shelf and pondering what the next crucial piece of equiptment I need may be.

 

[crossthread]

Bluechipx.... My Granddaughter calls that "Retail Therapy". When she gets a little down at college she goes and buys something. At first I thought this was just a girl thing but nope. Found out it works for me too. There is nothing like a new tool.

 

[ShaunM]

I really don't use the pressure washer much BUT I like extremes in everthing I do so I am attracted to the hot water option. Everytime I buy some new whatever it is like Christmas morning for a ten year old when the delivery truck pulls in my driveway! Carefully taking it out of the box, inspecting all the parts that came with it, throwing the instructions in the garbage, humbly getting the instructions back out of the garbage without my wife seeing me and finally playing with it before retiring it to a back shelf and pondering what the next crucial piece of equiptment I need may be.

This is so relatable I had to send it to my wife. I could feel her roll her eyes from her hotel room 300 miles away (business trip - which means more opportunity to sneak more "crucial equipment" into the garage).

 

[dalmatiangirl61]

I already have a diesel burner/coil, replaced the coil a few years back as it had rusted thru, but the burner does not have a thermostat, maybe I need to add one? Burner does cycle on/off when trigger is pulled. I do have 2 large water tanks on the trailer, wag maybe 200 gallons each, if I fill those then let them sit in sunlight for a few days to come up to ambient temp I can get hot water at the nozzle. If I hook directly to tap I just get warm water. I have roughly 150 ft of hose that runs to boomlift, then another 75 ft of hose on spool at base of lift that can spool out as boom is extended.

I really need to get a helper next time I try to run it, trying to run 2 machines falls into the problematic category......

 

[Homebrewblob]

I already have a diesel burner/coil, replaced the coil a few years back as it had rusted thru, but the burner does not have a thermostat, maybe I need to add one? Burner does cycle on/off when trigger is pulled. I do have 2 large water tanks on the trailer, wag maybe 200 gallons each, if I fill those then let them sit in sunlight for a few days to come up to ambient temp I can get hot water at the nozzle. If I hook directly to tap I just get warm water. I have roughly 150 ft of hose that runs to boomlift, then another 75 ft of hose on spool at base of lift that can spool out as boom is extended.

I really need to get a helper next time I try to run it, trying to run 2 machines falls into the problematic category......

Sounds to me the burner isn’t the problem (or is full of soot! Soot insulates!!).
I’m thinking your GPM is too HIGH for your heater, sounds like the water isn’t hanging out in the coil long enough to get hot. If your heater has no thermostat, it surely has a “thermal” limit trip of some sort right?

I would check the GPM of your pump and compare to the GPM of your heater.

The 4000psi dewalts are around 4gpm and the heaters are 4-6gpm I think so we’re pretty closely matched.

I would probably sell your setup and build your own. We NEVER had luck with the all in one setups on wheels, they was always terrible.

And for the price of some of these “all in one” units you could really build 2 or even 3 setups of your own WITH wheels.

Is yours an “all in one” on wheels?

Oh! You could test my theory out by running a smaller nozzle on the end of your wand and checking to see if the temp is hotter, with no tip in out gun we get NO pressure but the water STILL comes out toooooo hot to touch!

 

[dalmatiangirl61]

Sounds to me the burner isn’t the problem (or is full of soot! Soot insulates!!).
I’m thinking your GPM is too HIGH for your heater, sounds like the water isn’t hanging out in the coil long enough to get hot. If your heater has no thermostat, it surely has a “thermal” limit trip of some sort right?

I would check the GPM of your pump and compare to the GPM of your heater.

The 4000psi dewalts are around 4gpm and the heaters are 4-6gpm I think so we’re pretty closely matched.

I would probably sell your setup and build your own. We NEVER had luck with the all in one setups on wheels, they was always terrible.

And for the price of some of these “all in one” units you could really build 2 or even 3 setups of your own WITH wheels.

Is yours an “all in one” on wheels?

Oh! You could test my theory out by running a smaller nozzle on the end of your wand and checking to see if the temp is hotter, with no tip in out gun we get NO pressure but the water STILL comes out toooooo hot to touch!

It may have had some wheels, and I guess it still does as its the 2 big tanks and the pressure washer/heater unit mounted on a 16ft trailer. I am using a wide spray nozzle, possibly too large of an orifice? The job is removing latex paint from old style soft bricks with lime mortar, trying not to damage the bricks or blast out the mortar. Even with the wide tip the mortar does require touchup.

 

[Homebrewblob]

It may have had some wheels, and I guess it still does as its the 2 big tanks and the pressure washer/heater unit mounted on a 16ft trailer. I am using a wide spray nozzle, possibly too large of an orifice? The job is removing latex paint from old style soft bricks with lime mortar, trying not to damage the bricks or blast out the mortar. Even with the wide tip the mortar does require touchup.

Yeah I would go with a smaller Orifice and see where that gets ya! I’d say a smaller orifice should raise your pressure but “soften” the Impact on the mortar as well, we’ve noticed with smaller tips (same or nearly the same spread) we get a higher pressure but less volume giving a “softer” hit at the same range. We call them the “sniper tips” because we use them in tight areas and hard to reach places when we don’t want to wear the backsplash and grease on ourselves.

And bonus for you is less water usage!

 

[idacal]

I'm probably saying something that every one knows, but tips need to be sized to the machine, that's what controls the psi, at least on electric. I did away with all the quick connects, everything is threaded, because of the oring issue it would blow and that was it for the day. here is a tip chart Pressure Washer Nozzle Selection Guide I had the local pressure washer guy get me a real rotating nozzle he said with hot water to step it up a full nozzle size otherwise they would not live long. it kind of roars like turbine, have to were plugs with it, but it cut our washing time in half. it was taking 3 to 5 hours to wash a rig now its about 2 this is with a 2900 psi ,5.5 gpm electric 11 horse motor. I pulled the burner tip think it was a 3 gallon an hour tip so it uses diesel pretty good.

 

[Big B]

A few years ago I used hot soft water in my Honda powered pressure washer and it worked great on old grease and other hard to remove crap on my tractor. Sadly the pump only lasted about 15 or 20 minutes before it was shot. Little over a hundred dollars later it was working again. Probably be more with the bigger pressure washers.

 

[Homebrewblob]

A few years ago I used hot soft water in my Honda powered pressure washer and it worked great on old grease and other hard to remove crap on my tractor. Sadly the pump only lasted about 15 or 20 minutes before it was shot. Little over a hundred dollars later it was working again. Probably be more with the bigger pressure washers.

I don’t think it’s wise to run hot water INTO any pressure washer pump. I would only ever advocate heating the water AFTER the pressure washer pump!

We so far have only lost 1 pressure washer pump.

When we was just starting out A green horn dropped the Pressure washer out of the back of the van while unloading it and hit the pump output quick connect on the bumper. Snapped a huge chunk off the pump and turned it into a paper weight.

I still have the Honda motor from that setup sitting in the garage waiting for a project to form.. man I really need to get my shit together!

That was about 7 or so years ago. Since then we’ve tried to buy “quality” stuff.

Really want some pretty yellow Karcher steam washers! But BOI ARE THEY SPENDYYYYY

 

[Strostkovy]

If you get the pressure high enough the water will get very hot as it leaves the nozzle.

I completely forgot how to do it now but I used to do that math on hydraulic relief valves.

 

[Bluechipx]

I bought the Northstar one, should have it the middle of next week, thanks to those who recommended it! All I need now is way to cover it from sight from 99% of my borrowing friends, you know, the ones that really should have their own but don't quite feel like spending any of their own money, which of course is more valuable than my money. On the positive side, I get to visit them at their homes when I need to get my things back.

 

[Homebrewblob]

I bought the Northstar one, should have it the middle of next week, thanks to those who recommended it! All I need now is way to cover it from sight from 99% of my borrowing friends, you know, the ones that really should have their own but don't quite feel like spending any of their own money, which of course is more valuable than my money. On the positive side, I get to visit them at their homes when I need to get my things back.

I’m sure you’ll be happy with it. They sell coil protector. We use it only when we have a gap in the schedule, I don’t know about using antifreeze or pool/rv winterizer but I’ve heard others do it.

What I’m saying is don’t leave water sitting inside the coil as it will eventually rust out the coil (as with any water handling equipment)

And you said you like the x-mas feeling of getting something new!?

Well get ready to have the fuzzies because that bad boy should show up on a pallet and it’s mostly together but you still get to put the wheels and handles on! Lol.

Run her at 250 and don’t look back.

Also as I said before soot really insulates the coil and causes ALOT of heat to just skip the coils and go out the top!

In the manual you’ll find a procedure for setting the A/F ratio (elevation) on the burner, it’s super simple so just make sure she’s not rolling coal like Detroit diesel in a tractor pull and you should be good.

They come “primed” and tested so you should be able to fire it right up even on a empty tank. (The clear Fuel filter will be full)

Post pics when you get it and let us know how you like it!

 

[Bluechipx]

I’m sure you’ll be happy with it. They sell coil protector. We use it only when we have a gap in the schedule, I don’t know about using antifreeze or pool/rv winterizer but I’ve heard others do it.

What I’m saying is don’t leave water sitting inside the coil as it will eventually rust out the coil (as with any water handling equipment)

And you said you like the x-mas feeling of getting something new!?

Well get ready to have the fuzzies because that bad boy should show up on a pallet and it’s mostly together but you still get to put the wheels and handles on! Lol.

Run her at 250 and don’t look back.

Also as I said before soot really insulates the coil and causes ALOT of heat to just skip the coils and go out the top!

In the manual you’ll find a procedure for setting the A/F ratio (elevation) on the burner, it’s super simple so just make sure she’s not rolling coal like Detroit diesel in a tractor pull and you should be good.

They come “primed” and tested so you should be able to fire it right up even on a empty tank. (The clear Fuel filter will be full)

Post pics when you get it and let us know how you like it!

Everything Homebrewbob said was exactly spot on! From the time the delivery truck slowly backed down my driveway, the unwrapping of the plastic wrap cover, removing the lag bolts from the skid, the 'new smell' and admiring the perfect fresh, flawless pretty red paint, well, if I remember a Seinfeld episode, something may have 'moved'. It actually might be a bit too good though, I started it up and after a minute or so of spraying (the pressure gauge on my pump read 4,200 psi) steam appeared in the water spray and the wand started getting warm. I had a Cincinnati #5 vertical mill in my driveway that had a badly stained base with old coolant and grime 1/4" thick that I thought would be a good test subject. It has a 8" "I" beam frame attached under it to allow for a longer knee elevation screw, so I started on the "I" beam and it quickly got a gray sandblasted look to it. As I raised the spray to the grimey painted base, the paint disappeared instantly leaving almost bare cast iron. I guess you have to get back a few feet and slowly find the right nozzle the part distance which will take some practice.
The coil used for heating is lightly rusted so it would have been nice to see stainless there instead of steel. I imagine the inside of the coil is super clean after use so the rust will start within seconds like a freshly cleaned cylinder bore. Just draining the coil would help but running some other rust stopping liquid though it would be better. Possibly draining the coil followed by a quick start of the burner for several seconds would dry the water out of the tube? Any good ideas here?

 

[DDoug]

Making the coil of stainless would entail much more coil.
Ref. the heat xfer numbers in your machinist handbook.

 

[Homebrewblob]

We don’t use any protection on the coil unless it’s gonna be sitting for awhile. I think unhooking the lines and blowing some compressed air though it should probably do 75% of the job at least. I wouldn’t light it without water pressure in the coil. You’ll get hit spots and localized steam doing that and I don’t think (IMO) the coil would like that.

antifreeze and coil protector have rust inhibitors but I’m not sure about the pool/rv stuff.

We clean food equipment so we cant use regular antifreeze.

What we do is have a plastic “bottle” hung in the van above the Height of the coil, we plug the bottle to the coil and let gravity back flow the coil and till we see it leak out the other end.

At 250F you’ll have wet steam, that’s where we like to play!

A stainless coil would also increase price pretty significantly I would assume but would be nice agreed.

Try holding that wand at 250F for 2 hours at a time wide open!
We run ours on diesel.

These heaters are all we’ll be buying for awhile! So far (knock on wood!) we haven’t had a single failure.

Can’t say the same for Our dewalt pressure washers! had 1 failure so far, unloader valve got stuck open and another oopsi when I tried to remove the quick connect in favor for a solid direct connection, never seen so many seals and springs come flying out!!!!

Had to check the manuals exploded view To make sure I had all the pieces and in the correct order.

Have fun and REMEMBER! Water injection injury’s often lead to amputation!

Treat the wand like a .45 cal m1911! And only point it at things you wish to “destroy”







Also pics!!