Intex QX2600 Sand and Salt water system: error code 90

deltaout

New member
Mar 23, 2025
3
Europe
Hello everyone,

First time posting here.

Hopping someone has an idea. With spring coming I figured I'd prep the pool in advance for the hotter days. I've had this QX2600 combo since 2022 and it has worked great but of course is no longer under warranty. I got it because the paper filter pumps they give you with the pools are utter garbage and I needed something powerful that would make cleaning the pool easier. Sadly a proper pool is, at least for now, not in the budget. We have 2 kids which is mainly why we have a pool :)

The problem:
I get a code 90 after about 30 seconds and the pump beeps continuously flashing the low flow pump light. However the flow coming out on the pool side feels strong just like it always has.

I have tried everything and watched about every youtube video on the subject and it seems like people are more or less fixing their code 90 with sheer luck.

Here's what I've tried so far:
- changed the sand yesterday which was pretty annoying to do. They old sand was pretty dirty. I was hopeful this would be it but no. Intex sand wasn't available anywhere so I got some quartz sand for sand filters instead.
- while changing the sand, I cleaned every part of the assembly to ensure there was nothing blocking something off somewhere. I've cleaned the basket, opened the plastic part to check the impeler, every tube, the white filter under the top part of the thing were you choose your mode with the handle...
- After changing the sand I backwashed and rinced. The water is as clear as it can be
- Took a look at both electrodes in the little tank that is right after the sand filter (see picture below). One of them had very minor build up. Both of them look fine and there's no corrosion on the inside of the plugs on the electrical parts. I've cleaned them off and gave them a 1h bath in white vinegar
- In filter mode the pressure is just above the green, slightly in the yellow which I find odd since the sand is new. If I put the pump in recirculate, the pressure does drop into the green, but the code 90 still comes up after ~20-30 seconds. So most likely the problem isn't with the sand or the filter.

I can shake the feeling that this comes down to maybe a bad flow sensor that tricks the pump into thinking it doesn't have enough flow. I just don't know where that flow sensor is, is it integrated with one of the 2 electrodes since it appears to be electronic and not mechanical in this version?

Appreciate any help on the subject!

intex-qx2600-sand-and-filter-combo-code-90-low-flow-pump-v0-f6a8kt56ueqe1.png
 
The flow sensor is electronic inside the titanium electrode...

1742759876999.png
 
The flow sensor is electronic inside the titanium electrode...

View attachment 633948
Ah good catch thanks.

I contacted intex who said I should buy a new pump because code 90 is usually due to the control station. According to them, this way I'll benefit from a 2 year warranty. What a joke, that programmed obsolescence is worse that smart phones...think I'm going to try buy the electrode first