White Magic Water Pressure Loss | TruckMount Forums #1 Carpet Cleaning Forums

White Magic Water Pressure Loss

rob allen

Staff member
Sep 5, 2007
Real Name
Robert Allen,Jr.
Business Location
United States

A white magic commander HP. Did a flood job and turned the switch to water recovery and started the job. Went outside and the machine was steaming.

Now the machine only will only go up to 300-350 psi.

Where do I start? pressure reg or pump seals is my guess.

These things are a plumbing nightmare.


Poss solutions;

I bet the exhaust diverter is stuck on heat mode and the exchanger over heated.


There is a possibility that the nut behind the pressure knob vibrated out and is keeping the knob from being turned in far enough to increase the pressure. Mine has backed out a time or two.

Other than that, it sounds like the unloader or regulator is damaged. Even in water suck mode they will still overheat with the heat not running through the exchangers. Very poorly designed machine.

These things ARE a plumbling nightmare. It has alot of quirks about it. Will I be buying another one? Ah, no.


All it would take is for a an engine exhaust Diverter to not fully close on a water extraction and you will boil the remaining water in the HX to live steam over a period of 20 mins. Steam may have very well worked it's way back to the regulator/unloader or pump head....cooking the pump checkvalves.

It is the downside to diverted hX designs, and yes White Magic is a plumbing nightmare, .what were they thinking, a pic of the rats nest would make you roll your eyes.
Jun 23, 2010
North Carolina
Real Name
Justin Todd
Business Location
United States
your problem was not in the diverter valve, I am a truckmount service tech for 5 years and we have been in the business of truckmount repairs for 15 years, i will tell you from my experience, it sounds like your bypass system was not working that was the root cause, and then the hot water melted the check valves in the pump, white magics have a bypass system to prevent overheating in winter and recovery mode. there is a quick connect on the bottem right hand side of the machine torward the back it plugs into the fresh water tank, unplug it and take the female quick connect off, turn your machine on and flip the recovery switch, if water does not shoot out of the hose you just disconnected then you have bypass problems, and about your diverter it is suppost to stay in heat exchange mode untill it either bypasses or your in water recovery mode.

Your root problem is a bypass problem possible causes ( bypass solenoids, solenoid filter, temp switchs)

your new problem due to over heating ( melted check valves, possible melted regulator, possible melted temp shut off, possible melted temp sensor)

i hoped this helped and if you have anymore questions about anything send me a message, i am well knowledgeable about caret cleaning truckmounts and equipment and i do this 8 hours a day.


New Member
Jan 13, 2012
north carolina
Real Name
Brian Miller
Business Location
United States
the plungers in the white magics are plastic u might have melted the plastice plunger allowing water to by pass. undo the quick disconnect and put a bleeder in it. if water comes out of the bleeder u have to replace the plastice plungers


New Member
Dec 25, 2016
Real Name
John Hernandez
I too have a commander ho,, I recently bought it cheap,, but my problem is that the water does not get hot, in spite the diverters working properly,, they open and close,, the thermostat capillary tube is bent at probe and I feel that might be my problem. Is there a place I can buy this thermostat, because everybody sell a different one, and dont know if I can modify. Thanks,,, This is my first post,,, All the way from Raleigh, NC,,, You wont believe but I bought the machine for only 400 dollars with a new cat pump that had not been oiled at all, I was the first user...

ron Tabb

Active Member
Sep 13, 2015
Real Name
Ron Tabb
Call Brian at
New England Truckmount he stocks
white magic parts


New Member
Jul 16, 2014
I had a some what similar problem. I also have a HO. Turned out to be the pop off value. Toward the end wouldnt go over 200 psi. It is on the back top left of the machine. The peace inside decenigrated.