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AquaCure low and high level sensor adjustment 

Here’s my FAQ Notes on how to easily fix.  

Here is a video to help you to Adjust AquaCure Liquid Level Sensors

You’ll need two screwdrivers.  Sorry for the instructions length, but I tried to be comprehensive.  The fix is simply to turn a tiny screw (for which you can make a tiny screwdriver by shaving a toothpick).

First note that some people suddenly have their high level sensor ‘activate’ inappropriately after they ‘clean’ their AquaCure.  The sight tube shows that the fluid level is not high, but the sensor is saying that the reservoir is too full.
This is perfectly possible if the orifice(s) to the reservoir have become plugged, so that the reservoir cannot ‘drain’ properly.  Thus, even though the sight tube and the main electrolyzer are not ‘too full’ the reservoir (where the level sensor is located) is actually too full.

The ‘proper fix’ is for this to clear the blockage out of the lower (or upper) reservoir orifice, which can usually be done with multiple hot water rinses (refer to maintenance rinse instructions).
If rinsing doesn’t work, the plug may need to be physically removed.

If there is no ‘plug’ the sensor can still be sounding the alarm after an overfill situation due to some sort of ‘residue’ left over from the overfill, which makes the sensor more sensitive.  You just need to turn down the sensitivity (see below) and it’ll work properly after that.

Another issue is if the high level Sensor Slipped out of position

First, the upper liquid level sensor may have slipped down (wiggled loose in shipping or during maintenance rinsing).  We recently had this happen on a couple of machines.

We are now fixing every one in place with double sticky tape as well as the zip tie, but you may have received a machine that was built before that change.  The zip tie is usually enough unless there is an extraordinary ‘event’ to cause the ‘slippage’.

So this is the first thing to look for once you get inside the machine.  

So, take the AquaCure housing lid off (I won’t void your warranty for following my instructions).

4 top (handle) screws and 4 screws on each side, (put them in a bag to prevent loss).
Take off the black water fill cap or the Tower Cap (as appropriate).

You may see the black plastic ring around the fill stem come unsnapped as you lift off the cover.  I’d ‘resnap’ it together now so it’ll be properly in place when you replace the cover.
If it comes loose (into two pieces) then the top piece goes on first and the bottom piece snaps onto it from underneath, to hold it into the hole in the cover (and make everything look nice).  The ring also helps prevent the Tower Cap from wiggling too much.

Be CAREFUL when running the machine when the cover is off.  The electrolyzer side is low voltage 28 VDC and fairly safe.  The power supply side has high voltage.  Just don’t touch any wires or terminals when the machine is turned on.

The high level sensor is strapped onto the side of the tall white plastic chamber (the reservoir tank).  There are two sensors, obviously it’d be the top one.
Compare the upper sensor to the position in the picture.
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The  ‘slipped sensor fix’ is just to move the sensor(s) back into position and it should work fine.  

The bottom of the lower sensor should be 1.75 inch above the upper lip of the lower cap. 

Upper (high level) Sensor Adjustment
The next thing that can go ‘wrong’ is the high level sensor can go ‘out of adjustment’ (become too sensitive).
This issue occurs about once in a hundred machines (if this is the case sorry, your lucky day).

If the high level sensor is too sensitive and needs to be adjusted, there is a tiny adjustment screw on the side of it.

It can happen that the sensor becomes more sensitive after it was factory set (it’s an electronic thing).  

Once re-set, it should be fine because it’ll be customized for YOUR machine in YOUR location (placement of wires, temperature, etc. all affect it).

Assuming that you have fluid in the machine, the bottom red light (on the sensor) SHOULD BE ON.  A red light on the sensor indicates that there is water being ’sensed’ (assuming of course that the capacitive sensor is adjusted correctly)

The electronics takes the signal from the sensors and lights up the AquaCure Front LEDs appropriately. 

So an indicator light on the lower sensor (showing there is water) tells the circuit board that the lower water level is OK and the circuit board does NOT light up the Red LED on the front of the AquaCure. 
If there isn’t enough water (or the sensor is miss-adjusted), the sensor light will not be on and the circuit board WILL light up the low level LED on the front of the AquaCure.

An indicator light on the upper sensor says there is water (and thus too high a liquid level) so the circuit board DOES light up the AquaCure high level LED.

If the sensors are in position and not signaling appropriately for liquid level then 1 of two things are (usually) the issue.

1. plugged fluid orifices: so the reservoir has a ‘fixed’ too high or too low of liquid level because the fluid can’t flow in or out.  The FIX is to clear the orifices, which can usually be done with multiple hot water rinses.  Usually if the white ball is floating free, the orifices are not plugged.

2. The sensors become miss-adjusted.  We do not know why this happens.  It’s an electronic thing.  But sometimes (about 1%) when the customer sets up the AquaCure (or does the first maintence rinsing), the High or Low sensor needs a tweak to re-set it properly.  We don’t know what it is that causes this, but once re-set at the customer’s location, they work reliably.

I’d guess our time for adjustment would be in the 10 minute range (hood off to hood on) and it would be FIXED, no more high level alarm, except when there actually IS a high level.

Once done you’ll have no more issue with it.

You’d need a Phillips head to remove the hood and a tiny flathead (like to tighten spectacle screws) to adjust the sensor screw.   Can use a tiny anything, one woman even just made a flat edge on a toothpick. 

Make sure the fluid level is slightly higher than the ‘full’ line on the sight tube but not ‘over-full’.

Don’t depend on the white plastic ball to assume the fluid level.
As I point out in the Manual, you cannot depend on the little plastic ball in the sight tube to float properly.  I put it in there to help see the fluid level line (the meniscus), and it does great when it works, but it can get stuck to the side of the tube and/or get some lye crystals on it which causes it to sink.

So check inside to be sure the liquid level is correct, (use a dip stick.  A chop stick works well)

The plastic block itself, not the standoffs, is about 5 3/4” (14.5 cm) from the top of the silver water fill pipe.

The FULL fluid level is about 5 1/8” (13 cm) from the top of the silver water fill pipe.

The testing and setting for OVER-Full should be done with the water level at about 4 3/8” (11 cm) from the top of the silver water fill pipe.

Turn on the AquaCure.

For the high level sensor: Turn the tiny adjustment screw clockwise 180° to make it less sensitive… then wait about 2 seconds for the electronics to adjust and if the alarm is still going off, turn it another 180° clockwise, etc.  KEEP GOING until the alarm shuts off.

You need to allow enough TIME for the sensor to ’settle’ as you adjust it everytime, so it got ‘confused’ until it sorted itself out.  You need to wait at LEAST 2 seconds after each adjustment to let the sensor ’settle’.  
Continue turning unto the alarm does NOT come on when the AquaCure is full as described above.

It helps to quickly getr ingto the ballpark to just keep turning (without taking your hand away) until the alarm shuts off, then adjust by tweaks to get it accurate.

Those liquid level sensors are very reliable, but sensitive to adjust.

Also you’ll notice that as you get close to the sensor with your fingers or screwdriver, that it will alarm.  That’s because it ‘senses’ the mass of these objects.  So to get a true setting, you need to move your fingers and screwdriver away from the sensor.

(picture of tube on syringe)
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Once the high level sensor is adjusted, IF NEEDED, suck the excess fluid out (I use a tube stuck on the end of the syringe.  I cut 6” off an 1/8” ID by ¼” OD vinyl tube) 

or pour out the extra fluid.  Take care because the fluid contains lye.  
I’d save this fluid to put back into the machine when it needs more water, so I’d be putting the lye back into the machine.

I save lye solution in glass mason jars with plastic lids like this:

When the liquid level is FULL (about 5 1/8” (13 cm) from the top of the silver water fill pipe) check the sight tube to see that the liquid meniscus (fluid line) is at (or close to) the FULL line.  It’s nice if the white ball is also floating there, but not required for proper machine operation.

When you replace the AquaCure hood, taking care NOT to strip out the chassis threads.  Tighten the screws gently until JUST tight.

It helps to do the top 4 (handle) screws first, but leave them loose, then the bottom 4, leaving a little loose, then the middle 4 tighten them but be sure to push in the metal, don’t have the screw pull in the metal or you’ll strip out the thin threads in the metal.  Then tighten the other (loose) 8 screws.

Do NOT depend on the screws to ‘pull’ in the tin or you’ll strip out the threads in the housing.
It’s good to leave all the screws a little loose until they are all in place, so some movement is possible to line up the holes.

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