Intellichem flow sensor issue when a valve is turned 1 way but not the other

[Mikekantro]

I have an issue - and a question. Right after my multiport filter value there is about 12 inches of straight pipe and then a 3-way value that bypasses the heater. Now .... i notice that when i bypass my heater, my GPM on my VSF pump increases. This makes sense as I’m skipping the heater, and reducing “head?” loss.

OK - here Is the odd part - between the filter and the value there is a water feed that goes into a water sampler for my intellichem. When i run the water through the heater there is plenty of flow to “turn on“ the intellichem magnetic flow sensor.

However, when i turn the value to bypass my heater (which remember produces higher GPM at the same RPM), there isn’t enough flow to activate the intellichem magnetic flow sensor. i disconnected the flow line that goes into the intellichem system, and was able to see a noticeable drop in flow when i bypass my heater with the value.

Only thing I can think of is the 90 degree elbow somewhat limited the flow into the intellichem? Is there a better spot for that in feed? This is also an out feed that is plumbed in before my SWG.

End goal is to replumb the pipes to create a actuator bypass for the heater - don’t use the heater that much and ive noticed tremendous head loss. Issue is that i want to keep the UV light so bypass value on the heater and then go to the UV then to the SWG. Need to repipe some stuff... any ideas? A

 

[Jimrahbe]

Mike,

Does the IntelliChem sensor work off of flow or pressure? My guess is pressure. When you by-pass the heater the back pressure goes down and allows for more flow, but less pressure.

I also suspect that if the UV system died today you would never know... Do you use the UV because you have an auto-cover?? If not, and you are replumbing anyway, it might make sense to add a by-pass for the UV and see if it is really something you need and/or if it is causing a flow restriction.

I am pretty sure that the power plant on an aircraft carrier has less plumbing...

That said, I am impressed with the plumbing work..

Thanks,

Jim R.

 

[Mikekantro]

I like having the UV with the assumption I can maintain a relatively lower level of FC. The UV "came with the pool" before I knew anything about pools. I don't mind having it. It turns on with the main pump and I run the pump slowly at night to water is going through the UV all day/night. I get that its a bit overkill. Before I start replumbing anything,I want to know why the intellichem isn't working.I think it get what you are saying...I saw a visible difference in the flow and pressure(?) when I unhooked the black intellichem tube from the sample container. Sooooo how do I get both high pressure and high flow at a lower speed? why would the pressure drop when bypassing the heater and the UV?

 

[Mikekantro]

this is from the manual :

Flow Cell Inlet and Exit Lines

1. It is essential that the supply line be at a higher pressure than the discharge line so the water will flow through the cell at a steady rate in the right direction.
2. Inlet should be installed after filter and before heater. Note: Plumb the INLET before the solar valve.
3. Exit should be installed after heater and as far away from any equipment as possible.

Maybe the pressure is too high on the exit line too?

 

[Jimrahbe]

Mike,

It appears they are using the pressure increase caused by the heater to give you the differential between the input and output of the IntelliChem.. If you have a 10' pipe with water flowing through it, you will not any any real pressure difference. I can see where you have the input to your IntelliChem connected, but not sure where the output is connected.

Thanks,

Jim R.

 

[Mikekantro]

the output, or exit, you can see on the second photo all the way on the bottom of the photo.Follow the exit of the UV all the way down to the bottom of the photo and you will see the black tubing going in. they may be no pressure differential because I'm bypassing the heater and the UV.

 

[Jimrahbe]

Mike,

That is the same thing I am thinking.

My "guess" is that putting your input before the pump would be too much pressure, but really have no idea.

Let's see what ideas others might have... Calling @JamesW Calling @bdavis466

Thanks,

Jim R.

 

[Mikekantro]

maybe I can move the exit flow line after my SWG - perhaps that will create enough difference.

Calling @JamesW Calling @bdavis466

 

[bdavis466]

The systems that seem to work the best have the exit flow into the bottom drain of the pump basket. These systems can still operate at low pump speeds.

You need a very large pressure differential... the filter, heater and SWG just aren't enough.

 

[Mikekantro]

I haven't come across that recommendation yet - do you have any photos of what that would look like or other threads to point me to? thank you for your advice @bdavis466

 

[bdavis466]

There's a threaded port on the bottom of the pump basket with a threaded plug in it. I believe its 1/4 NPT

 

[bdavis466]

Anywhere on the suction side is fine. The pump basket is already threaded though so that might be a little easier.

It isn't published anywhere in Pentair's manuals but I know there tech support has been recommending this installation when people have problems.

Screenshot_20200414-065712_Chrome.jpg

• bdavis466
• Apr 14, 2020

 

[Mikekantro]

thank you... any good way to plug up the old hole?? thanks again!

 

[bdavis466]

thank you... any good way to plug up the old hole?? thanks again!

Just cut the pipe over the hole and glue in a coupler or use a threaded plug