Need help converting a hot water pressure washer | TruckMount Forums #1 Carpet Cleaning Forums

Need help converting a hot water pressure washer

Calbert2016

New Member
Mar 15, 2016
5
0
1
Real Name
Corey Spence
I have an oil fired hot water pressure washer, 3.5gpm, 3000psi. I was thinking I could use the pressure washer for a hot water source and maybe attach an upholstery tool to it or something. So here is what I did: I plumbed a low pressure unloader valve before the boiler to bring the pressure down for the upholstery tool. But when I tried to use the tool the boiler wouldn’t turn on. It turns it's out the pressure switch for the boiler fuel pump wasn't activating because of low pressure. The switch needs 250 psi. If I turn the pressure up the upholstery tool puts out way too much water. I'm I missing something? I thought this would be an easy thing to do, but I can't get it to work. Any help would be greatly appreciated.
 

seagrtj

Well-Known Member
Jun 28, 2011
1,294
526
113
MO
Real Name
Todd Seagraves
Business Location
United States
I would first start out asking why your trying to use a pressure washer to do upholstery?

but.. then I would ask... Are you using a true upholstery tool or a generic hand/detail tool. A good upholstery tool has a flow control valve on it to regulate the water flow so you don't have to worry about adjusting the pressure back at your pump source.
 

LookNGood

Well-Known Member
Mar 17, 2014
4,311
1,677
113
Real Name
Joe P
I would first start out asking why your trying to use a pressure washer to do upholstery?

but.. then I would ask... Are you using a true upholstery tool or a generic hand/detail tool. A good upholstery tool has a flow control valve on it to regulate the water flow so you don't have to worry about adjusting the pressure back at your pump source.
Everybody says that, but that's not exactly true.

The flow valve does not directly adjust pressure, it adjusts FLOW.

If you reduce flow you will also to some degree lower the pressure. Pressure is force per area and is related to how many particles hit that area as well.

But if you have your machine running at 1200 psi cleaning tile and then try to use the flow valve to lower it, that's not going to happen.

The reason most people get away with using the flow valve to reduce pressure is because they were just cleaning carpets at 4-500 psi.

I'm not going to conduct some week long experiment to prove it to you, but please trust me.

It is always best to adjust the pressure at the source.

To the op I simply don't think this is going to work.

You would probably have to put an unloader on the output from the pump with some sort of bypass to relieve excess pressure so you can get down to less than 500 psi. Probably not going to be as easy as you'd like.

You would probably have an easier time buying a 250 psi pump and then running it through the heater to your tool.
 

TopJobROd

Active Member
Apr 11, 2013
155
56
28
55
Des Moines Iowa
Real Name
Rod Snyder
Business Location
United States
The heater requires a certain amount of flow or volume before the burner will run, not necessarily pressure, that way the water won't end up being superheated or with you getting a "vapor lock". My El Diablo requires 1gpm I believe so the upholstery tools that I have don't have enough "flow" to be able to use the heater. I clean all my upholstery with a portable equipped with a heater. I actually think that's why the new generation of tools are set up the way that they are. I am just too "old school".
 

Calbert2016

New Member
Mar 15, 2016
5
0
1
Real Name
Corey Spence
Thanks for the replies.
The bigger truck mounts have the capability of pressure washing, adjustable up to 3000psi 5.5gpm, such as ProChem Everest. Truck mounts and pressure washers all use basically the same components. The main difference being the drive motor. The truck mount motor is larger because it has to drive the vacuum pump/blower and the water pump, were a pressure washer just has to drive the water pump. I did put a variable unloader (100-3000psi) in as LooNGood suggested but it didn't work as planned. The pressure washer has a pressure switch to activate the boiler. It wasn't kicking in at the flow and pressure I needed. I'm now thinking I need to look at a flow switch instead of a pressure switch. Or have a high pressure and a low pressure loop. I just don't know what type of unloader I woulds use for the low pressure loop, or maybe I would use a pressure regulator instead?
 

Calbert2016

New Member
Mar 15, 2016
5
0
1
Real Name
Corey Spence
The heater requires a certain amount of flow or volume before the burner will run, not necessarily pressure, that way the water won't end up being superheated or with you getting a "vapor lock". My El Diablo requires 1gpm I believe so the upholstery tools that I have don't have enough "flow" to be able to use the heater. I clean all my upholstery with a portable equipped with a heater. I actually think that's why the new generation of tools are set up the way that they are. I am just too "old school".
That makes sense
 

Ara Klujian

Moderator & TMF Repair Expert
Moderator
Premium VIP
Jun 19, 2008
3,316
247
63
44
Chicago, IL
www.peterklujiancarpet.com
Real Name
ARA KLUJIAN
Business Location
United States
The heater requires a certain amount of flow or volume before the burner will run, not necessarily pressure, that way the water won't end up being superheated or with you getting a "vapor lock". My El Diablo requires 1gpm I believe so the upholstery tools that I have don't have enough "flow" to be able to use the heater. I clean all my upholstery with a portable equipped with a heater. I actually think that's why the new generation of tools are set up the way that they are. I am just too "old school".
Top Job hit the nail on the head. It's a matter of flow rate more so than pressure. That is why it is called a flow switch. :) You will correct your issue when you use an upholstery tool with an open flow bypass. Kleenrite makes an upholstery tool that has one. And futhermore, you should be using a bypassed tool regardless of your non-firing issue, because an upholstery tool has such a small jet that even if you where using a heat exchanger you would not be regulating heat properly and it would take forever to get the heat from the TM to the tool inside a house etc...
Get yourself the proper tool and your issue goes away. :)
 

Ara Klujian

Moderator & TMF Repair Expert
Moderator
Premium VIP
Jun 19, 2008
3,316
247
63
44
Chicago, IL
www.peterklujiancarpet.com
Real Name
ARA KLUJIAN
Business Location
United States
One more thing... It wasn't terrible thinking to install a low pressure regulator before the burner. But all you really needed to do is swap out the spring on the original regulator for a spring that accommodates lower pressure.
 

ACP

Well-Known Member
Apr 9, 2014
3,750
2,683
113
36
Washington
Real Name
Bjorn Marshall
a sapphire upholstery tool or similar will help, youll at least be able to control too much water but not pressure like said above.

if you are running higher pressure with a constant flow upholstery tool and then dialing the needle valve down to make up for it your putting wear on the needle valve and over time youll need to keep turning it down. If my TM is at 400psi and I dial the needle valve down it will loosen itself from the pressure and will need to be dialed down again.


your burner requires a certain amount of water to flow through it to avoid burning up the coil.
 

TopJobROd

Active Member
Apr 11, 2013
155
56
28
55
Des Moines Iowa
Real Name
Rod Snyder
Business Location
United States
I was VERY surprised at how much difference can be made in the unloader by simply adding a very thin washer or "dressing" (grinding) one end of the spring down a little!
 

Calbert2016

New Member
Mar 15, 2016
5
0
1
Real Name
Corey Spence
Top Job hit the nail on the head. It's a matter of flow rate more so than pressure. That is why it is called a flow switch. :) You will correct your issue when you use an upholstery tool with an open flow bypass. Kleenrite makes an upholstery tool that has one. And futhermore, you should be using a bypassed tool regardless of your non-firing issue, because an upholstery tool has such a small jet that even if you where using a heat exchanger you would not be regulating heat properly and it would take forever to get the heat from the TM to the tool inside a house etc...
Get yourself the proper tool and your issue goes away. :)
Much apreciated, I didn't know there was such a tool. I'm still little green to the industry
 

Calbert2016

New Member
Mar 15, 2016
5
0
1
Real Name
Corey Spence
a sapphire upholstery tool or similar will help, youll at least be able to control too much water but not pressure like said above.

if you are running higher pressure with a constant flow upholstery tool and then dialing the needle valve down to make up for it your putting wear on the needle valve and over time youll need to keep turning it down. If my TM is at 400psi and I dial the needle valve down it will loosen itself from the pressure and will need to be dialed down again.


your burner requires a certain amount of water to flow through it to avoid burning up the coil.
After reading Aru's post, I did a little more digging and found a few different manufactures out there. How do you like your tool? Have you noticed a lot of water usage? I would think that when doing a couch it could use up to 30 gallons. If for instance the tool consumes 1 gpm of water with only a fraction of the water used for cleaning, the rest by-passed.? Does the tool by-pass all the time or only when the trigger is pulled?
 

Ara Klujian

Moderator & TMF Repair Expert
Moderator
Premium VIP
Jun 19, 2008
3,316
247
63
44
Chicago, IL
www.peterklujiancarpet.com
Real Name
ARA KLUJIAN
Business Location
United States
After reading Aru's post, I did a little more digging and found a few different manufactures out there. How do you like your tool? Have you noticed a lot of water usage? I would think that when doing a couch it could use up to 30 gallons. If for instance the tool consumes 1 gpm of water with only a fraction of the water used for cleaning, the rest by-passed.? Does the tool by-pass all the time or only when the trigger is pulled?
The tool im talking about only bypasses when the trigger is pulled
 

PistolPete

Well-Known Member
Sep 28, 2014
1,901
1,189
113
Real Name
Peter Dymond
You can also buy a low flow switch. Keen rite has them
This will solve your burner on issue, but when you use low water cleaning the water will never get hot so a tool like the sapphire scientific upholstery will keep the water flowing and the burner cycling.
 
  • Like
Reactions: Ara Klujian

Ara Klujian

Moderator & TMF Repair Expert
Moderator
Premium VIP
Jun 19, 2008
3,316
247
63
44
Chicago, IL
www.peterklujiancarpet.com
Real Name
ARA KLUJIAN
Business Location
United States
I have an oil fired hot water pressure washer, 3.5gpm, 3000psi. I was thinking I could use the pressure washer for a hot water source and maybe attach an upholstery tool to it or something. So here is what I did: I plumbed a low pressure unloader valve before the boiler to bring the pressure down for the upholstery tool. But when I tried to use the tool the boiler wouldn’t turn on. It turns it's out the pressure switch for the boiler fuel pump wasn't activating because of low pressure. The switch needs 250 psi. If I turn the pressure up the upholstery tool puts out way too much water. I'm I missing something? I thought this would be an easy thing to do, but I can't get it to work. Any help would be greatly appreciated.
The flow switch does not move in low pressure situations. I personally think the bullet is to heavy on the st6. I bet some sort of modification can be made to the bullet in order to make it move more easily..