flowswitch
- Thread starter Squirtgun
- Start date
Russ Johnson
Equipment Expert
The reed switch can go bad and does. The only problem I've ever encountered with the internals is the magnets coming out of the shuttle. If you've got an old speaker magnet or a good refrigerator magnet, you can test the reed switch. Slide the reed out of the housing, start the machine, turn the burner on, and slide the magnet up and down the length of the brass tube. The burner should go on and off.
Paul Kassander
New member
I agree with Russ the internals seem to hold up well on those units usually it is just the reed that wears out.
Russ Johnson
Equipment Expert
How big of a load are you controlling with the reed? They're a very low amperage (solenoid only) switch. If it's breaking the circuit to the ignitor or the motor or both, the thin contacts can weld themselves together. If you want to use it to control anything other than the fuel solenoid, you have to go through a relay.
Squirtgun
New member
Russ I think it only controls the fuel soleniod.Could the rig getting froze have caused it to fail.I had everything freeze up on the way to a job last month and that's when the flow switch starting acting goofy.
I also found oil blowing by the valve cover seal(left side by the muffler) so I need to get that addressed.
I also found oil blowing by the valve cover seal(left side by the muffler) so I need to get that addressed.
Russ Johnson
Equipment Expert
Get me the model and type numbers off your engine, and I'll look the parts up for you.
Sirocco Jerry
Active member
ST-6 flow switch ..for low flow
An additional technical note on the ST-6..
the magnets seem to get weak over time,
we've found that if you have an intermittant one,
or need it to work on a lower-flow..
you can clip 1 1/2 turns off the spring,
and grind 1/8" of the brass off the plug that holds it in,
and they work much more accurately.
otherwise.. ditto on what Russ said..
pay real close attention to elecrtical load, especially on 12 volts !!
..just the solenoid coil by itself is already almost 1 1/2 amps.
...................Respect the tech !
An additional technical note on the ST-6..
the magnets seem to get weak over time,
we've found that if you have an intermittant one,
or need it to work on a lower-flow..
you can clip 1 1/2 turns off the spring,
and grind 1/8" of the brass off the plug that holds it in,
and they work much more accurately.
otherwise.. ditto on what Russ said..
pay real close attention to elecrtical load, especially on 12 volts !!
..just the solenoid coil by itself is already almost 1 1/2 amps.
...................Respect the tech !
Chris Tharpe
New member
While were on these, I have an ST-6 that was perfect before I just refreshed the pump. Now the burner stays on instead of acting properly. Is there an adjustment for these to set the amount of flow that is going through it. The machine is 8.5gpm
Chris Tharpe
New member
Don't leave it for a minute or you will have a mess on your hands. Been there done that, If were going to disconnect when the machine does this we just open the ball valve and let it flow then the problems of blowing a coil are gone. We should probably get a couple of pop-off valves in our rigs. :slap:
Sirocco Jerry
Active member
testing an ST-6 flow switch
pressure switch is the worst tool in the box for reliability.
ONLY FLOW should actuate a heater...
when your coil blows-up, you'll change your mind.
To check your flow switch..
pull the plug out of the end, and check that the slider slides free,
and the magnet stays inside the slider.
If that's OK, carefully slide the reed out of the brass block
(away from the magnet). Start the machine and observe..
The heater should NOT be "on" without the magnet actuating the reed.
If heater fires up, replace the reed.
(You can double-check it with a ohmmeter.)
One more thing about the slider..
that guage port should never be in the down position..
the slider eventually wears a "fall" at the edge of the hole,
so the slider doesn't track straight.
If you want things to last, follow my lead.
pressure switch is the worst tool in the box for reliability.
ONLY FLOW should actuate a heater...
when your coil blows-up, you'll change your mind.
To check your flow switch..
pull the plug out of the end, and check that the slider slides free,
and the magnet stays inside the slider.
If that's OK, carefully slide the reed out of the brass block
(away from the magnet). Start the machine and observe..
The heater should NOT be "on" without the magnet actuating the reed.
If heater fires up, replace the reed.
(You can double-check it with a ohmmeter.)
One more thing about the slider..
that guage port should never be in the down position..
the slider eventually wears a "fall" at the edge of the hole,
so the slider doesn't track straight.
If you want things to last, follow my lead.
810f250
Griffs Services PowerWash
What makes the pressure switch the worst for reliability Jerry ?
Why would so many manufacturers put it on there if it was?
Thanks
Chris Tharpe
New member
Only one explode, the other was a defect that caused the insulation to fall and cause flames back onto the burner end cap. That story ended much better than the first one
Chris Tharpe
New member
Squirtgun
New member
You can loosen the screw that holds the reed switch and move it out in small increments.The reed switch used to have a brass housing and it seemed as though you could make adjustments if it was firing the burning as soon as you pulled the trigger.
Russ Johnson
Equipment Expert
There really isn't much for adjustment except, like Scott said, sliding the reed out some. But that's not really a fix, either. There's something wrong with your switch...the shuttle is stuck or the reed has or is going bad. It doesn't matter whether it's 2 gpm or 10 gpm, flow is flow..no flow is no flow. The switch SHOULD shut off when the water stops moving.