Hot Water Dragon Problems

PeakOfPerfection

New member
Okay...so last year I bought a Hot Water Dragon 8 GPM Unit. My plans changed and I tried to sell it on here without any takers. Okay. So...I own the thing. Stick it in my warehouse knowing full well I was going to be building another rig at some point. That point is now. Full blown Powerwashing/Roof cleaning rig. New rig is 80% complete and is turning out beautifully (NPR 15' Box truck build). Fired up the unit, cold section was tested a few days ago and it worked great with a Big Guy 4 Bar Surface cleaner. Sweet. So...today was the day to fire the burner up and make sure the hot section was working before I put it to work on a job next week. Now keep in mind, I am no stranger to burner systems...I bullt the only biodiesel fired structural drying mobile furnace in the United States called a BioDry system. It has a burner that is 5x the size of the one on the Dragon, complete with a Honeywell control panel system. So, this isn't my first go around. Put a diesel fuel line on and put a line on the return with a valve so I could bleed it. Tank is right next to the machine so no return to the tank is apparently necessary according to the manual. Time to test this puppy out and get me some hot water!

This...is where things go bad.

First, Fuel...spraying out. From behind the control panel?!?

W.T.F.???

Pulled the control panel off. Turned out that the fuel pressure gauge connector was really loose and kind of flopping around.
Tightened it. Ahhh...easy fix, but should have been tightened at the factory. Put the panel back on and fired it up.
Fuel again..but now it was spraying out. A LOT more. Sh!t.

Took the panel back off and discovered the reason why. The F-F threaded barrel which adapts the male barbed fitting to the male gauge input was split. This is why it was loose and why tightening it made no difference and why fuel was still spurting out. Don't have another barrel fittting in that size. Stick a bolt in the line, clamp it off. Don't really need the gauge to test things. Clean up all the spilled fuel as best as I can.

Okay...ready for hot water! Flipped the switch...the other end of the fuel pressure gauge line at the pump blows apart. Literally shreds itself. Fuel spraying EVERYWHERE. REALLY??? Quickly flip the power switch off.


Take the connector off, I'll just block the thing off...rummage...crap...of COURSE I don't have a screw of that size with that thread to block if off.
Sigh. Snip the line short to a good section, and clamp the heck out of other end.
Fire it up, fire up the engine, all the burner lights come on...sweet...hot water, here she comes!
Any day.
Heat?
hello?
Nothing.

No heat. Could be air in the line? Yeah, probably air in the line.
Bleed valve line blows off the pump, spraying me and the right side of my truck with diesel.
Neighbors start to move their children indoors to escape the extraordinarily colorful language now emanating from inside the white truck up the street.
Shut the burner off. Again.
Fix the problem. Fire it back up.
Burner lights come on...no heat, nothing.
Does it require some pressure restriction... or will it make hot water open flow? Don't know because the manual is nowhere to be found and isn't on the website.

Then...the engine died. Just shut off.
And won't restart. Plenty of gas in the tank. Choke, throttle, nothing.

So now I am covered in diesel fuel, the formerly clean and sparkling truck is plastered n slippery smelly D2, my hand is bleeding from the insanely sharp edge on the control panel.
The engine won't start. I smell like a refinery and I've given up and am heading for a hot shower.

Help.
 
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There is either a flow switch or pressure switch on the burner for your protection and safety. You need water moving for the burner to ignite, think of what would happen if the burner was on all the time. I don't have to imagine, I have seen people who have removed the flow switch and had the coils shoot in the air 100+ feet.

Can't help you with the gas engine, I gave up on gas driven pressure washers, too much hassle.
 
That's a tuff day at the office.
Some days you get the bear, some days the bear gets you.

Don't know much about the water dragon but if it has a pressure switch controlling the burner, then you need restriction. IIRC 800psi.On the engine , I would suspect fuel/carb problem from the unit setting for a year. Maybe the fuel vent.

Good luck with it.
 
I kinda figured it might be a pressure thing. If I can get it fired again I will stick a nozzle on it. Would be nice to have it heat open flow to fill my roof mix tank with warm water for winter roof cleaning.

As as for the engine, it started and ran perfectly a bunch of times no problem. Perhaps there is a shutoff switch for safety tied into the burner pressure switch....if so, need to figure out how to reset it. Owners manual disappeared long ago.
 
Have you tried to loosen the gas cap? Maybe a faulty vent on the cap. Or disconnect the low oil connector. Maybe a faulty low oil switch. Just a few things to check right off the bat I would check first.
 
Have you tried to loosen the gas cap? Maybe a faulty vent on the cap. Or disconnect the low oil connector. Maybe a faulty low oil switch. Just a few things to check right off the bat I would check first.

Thanks. I am 99% sure it is not a venting issue. I have a 30 Gallon tank onboard for gas (20 diesel) and each tank has its own 5/8" dedicated vent line with external vent, external fuel filler necks and caps and dedicated fuel gauges. I built this rig with the intention of having zero internal fuel spills or fumes and zero chem fumes or spills. This is why there was so much cursing going on...all that effort to remain spill and fume free and all I get is diesel spewed everywhere. All chem tanks have exterior fill stations with Camlocks and check valves, dedicated external tank vents and all chem tanks are fully sealed. 99% sure it isn't a fuel issue. There is plenty of gas in the gas tank.

I checked the the oil level before ever starting it initially but will check It again along with the oil level switch connector. Maybe some diesel got into the connector? I will be going to the parts supply store to get degreaser/bioremediator to clean up all the diesel that spilled, new dedicated diesel compatible fuel line to run to the guage, and better clamps and a hookup for the fuel pressure gauge. Might just have my local Parker Hose outlet make me up a Hydraulic type hose which can withstand several thousand PSI....then I won't ever need to worry about that line leaking again.
 
Thanks. I am 99% sure it is not a venting issue. I have a 30 Gallon tank onboard for gas (20 diesel) and each tank has its own 5/8" dedicated vent line with external vent, external fuel filler necks and caps and dedicated fuel gauges. I built this rig with the intention of having zero internal fuel spills or fumes and zero chem fumes or spills. This is why there was so much cursing going on...all that effort to remain spill and fume free and all I get is diesel spewed everywhere. All chem tanks have exterior fill stations with Camlocks and check valves, dedicated external tank vents and all chem tanks are fully sealed. 99% sure it isn't a fuel issue. There is plenty of gas in the gas tank.

I checked the the oil level before ever starting it initially but will check It again along with the oil level switch connector. Maybe some diesel got into the connector? I will be going to the parts supply store to get degreaser/bioremediator to clean up all the diesel that spilled, new dedicated diesel compatible fuel line to run to the guage, and better clamps and a hookup for the fuel pressure gauge. Might just have my local Parker Hose outlet make me up a Hydraulic type hose which can withstand several thousand PSI....then I won't ever need to worry about that line leaking again.

Call Largo Pressure Washers in Tenn and ask for Steve The Owner who built the machine.....Had problems with mine and finally drove there and they fixed it the same day,,,,
 
Okay...got the motor fired. Turned out to be a draw tube issue with the brand new Moeller fuel tank I just bought...seriously, a BRAND NEW tank. Wont draw if it is under 1/2 tank even with squeeze bulb. Filled tank to 3/4 full. So...engine is now firing. Had a new hose professionally built for the fuel pressure gauge. Fired it up and it blew ANOTHER line...again the purge line. However...this time I was able to get a reading on the fuel pressure gauge before once again having to shut things down. It was absolutely PEGGED! Called Gene and asked him what his pressure is at and he says about 100. This explains why the lines keep blowing out. So...Monday I will be making calls and getting to the bottom of this problem. Meantime, more oil dry is going down.



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SUC...FREAKING...SUCCESS! Took stuff apart. Turned out there was a piece of debris in the bypass output connector I bought at Lowes (plastic, issue with the casting). It was blocking the line. Cleared it out with a drill, re-tried, fuel line pressure back down to normal. Fired up motor...turned burner on and HOT WATER! Ran it for about 10 minutes...spewed out some miscellaneous pieces of white insulation from the burner output but otherwise is running normally. Just need to figure out a way now to pump hot water into the roof mix tank with the least amount of line blockage...i.e what is the minimum pressure/maximum flow that will allow the burner to run.


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FlowSwitch is a safer control anyway, but if the Pressure switch is being used as power to the ignitor, you need a small relay..
callMe for more on that.. I make a kit with diagram.
 
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