Sirocco Jerry
Active member
EVERYBODY needs to know..
the unloader adjusts the spike-pressure..
the "working-pressure" is a side-effect of that..
to adjust the system for "working pressure"..
you are going to find out how "sticky" your valve is,
by releasing the gun, and watching the "spike-pressure" or "trapped pressure"
..depending on whether your gauge is mounted before, or after the unloader..
If the gun is open, and the pressure is running 3000psi,
then you let go the gun, and spike jumps to over 3500psi..
replace that unloader, unless adjusting it makes the spike go down.
When you adjust back up to "max system pressure"..
you may be aiming at 4000psi, BUT..
IF you get to 3000 psi, let go of the gun and get a 3800psi spike or better..
what do you think the spike is going to be when you adjust working PSI to 4000 ??..
that's right.. spike will traumatize your stuff at 4800 psi..
NOT a good thing on the heater coil, not good for hose-ends, not good on swivels, ..nothing.
A Flow-actuated unloader is BEST.. spikes usually only go 50-150psi over working PSI set-point.
A good quality Pressure-trapping unloader will run 200-400psi brand new.
It's easier on the entire system, letting it bypass a little
than to "force" an extra 100psi out of your system.
..especially if it costs an extra 150-200psi addition to the spike.
"Spike pressures gone-wild" cause..
valve cages to crush, hose-ends to blow, heater-coils to blow.
pump rods to blast..
I'm sayin' GET A GUAGE !
and KNOW your system..
YOU are the "pit-crew" in maintenance concerns. Eh?
Since went there.. I should also make 2 more points..
1. You should have a Pressure Relief before, AND after a pressure-trapping unloader valve..
you need to protect the pump, AND everything in the trapped-pressure.
..especially if the heater stays on when that pressure-switch fails. ..Coils are expensive.Eh?
2.
for you'all with the 200ft plus hoses on those over-stuffed hose reels..
IF you put a gauge out at the wand..
you will be SHOCKED at what "spike-pressures" can be..
Remember.. a gallon of water weighs almost 8 lbs..
and it's traveling how fast down the throat of that hose, and the heater-coil before that ??
.. and the trigger-gun "slams-shut" when you release it..
I've seen spike pressures hitting 5000psi at the wand,
where the gauge on the pump never sees more than 4300.
I've seen pressure hoses swell-up, like a pissed-off rattle snake.:yikes:
IF you want hoses to last longer, you can add a "regulating-relief" valve
at the hose reel, and let it bleed-off the more gnarly spikes.
OR, just take all that "normally-unnecessary" hose from the reel,
..and enjoy longer-life hoses.
Quick couplers are cheap n easy.
Blown hoses lose customers. Eh?
the unloader adjusts the spike-pressure..
the "working-pressure" is a side-effect of that..
to adjust the system for "working pressure"..
you are going to find out how "sticky" your valve is,
by releasing the gun, and watching the "spike-pressure" or "trapped pressure"
..depending on whether your gauge is mounted before, or after the unloader..
If the gun is open, and the pressure is running 3000psi,
then you let go the gun, and spike jumps to over 3500psi..
replace that unloader, unless adjusting it makes the spike go down.
When you adjust back up to "max system pressure"..
you may be aiming at 4000psi, BUT..
IF you get to 3000 psi, let go of the gun and get a 3800psi spike or better..
what do you think the spike is going to be when you adjust working PSI to 4000 ??..
that's right.. spike will traumatize your stuff at 4800 psi..
NOT a good thing on the heater coil, not good for hose-ends, not good on swivels, ..nothing.
A Flow-actuated unloader is BEST.. spikes usually only go 50-150psi over working PSI set-point.
A good quality Pressure-trapping unloader will run 200-400psi brand new.
It's easier on the entire system, letting it bypass a little
than to "force" an extra 100psi out of your system.
..especially if it costs an extra 150-200psi addition to the spike.
"Spike pressures gone-wild" cause..
valve cages to crush, hose-ends to blow, heater-coils to blow.
pump rods to blast..
I'm sayin' GET A GUAGE !
and KNOW your system..
YOU are the "pit-crew" in maintenance concerns. Eh?
Since went there.. I should also make 2 more points..
1. You should have a Pressure Relief before, AND after a pressure-trapping unloader valve..
you need to protect the pump, AND everything in the trapped-pressure.
..especially if the heater stays on when that pressure-switch fails. ..Coils are expensive.Eh?
2.
for you'all with the 200ft plus hoses on those over-stuffed hose reels..
IF you put a gauge out at the wand..
you will be SHOCKED at what "spike-pressures" can be..
Remember.. a gallon of water weighs almost 8 lbs..
and it's traveling how fast down the throat of that hose, and the heater-coil before that ??
.. and the trigger-gun "slams-shut" when you release it..
I've seen spike pressures hitting 5000psi at the wand,
where the gauge on the pump never sees more than 4300.
I've seen pressure hoses swell-up, like a pissed-off rattle snake.:yikes:
IF you want hoses to last longer, you can add a "regulating-relief" valve
at the hose reel, and let it bleed-off the more gnarly spikes.
OR, just take all that "normally-unnecessary" hose from the reel,
..and enjoy longer-life hoses.
Quick couplers are cheap n easy.
Blown hoses lose customers. Eh?
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