1/2" line to Liquidator

[Blowout]

Has anyone installed a 1/2" line to their liquidator?

Reason I'm asking is because I have a variable speed pump and a bypass valve to eliminate the heater from the flow path. With the 3/8" line to the Liquidator and the bypass open eliminating the back pressure created by the heater, the Liquidator flow meter shows too little flow. I have to close off the bypass to create enough back pressure to flow through the liquidator.

With the bypass open, there is a significant increase in flow without any increase in pump speed.

I was thinking if the line ID was increased from 3/8" to 1/2" it might provide enough increased flow to the Liquidator so the bypass could remain open.

The other option is to install a chlorine pump system from the chlorinator.

Any thoughts? Thanks!

 

[Bama Rambler]

So the flow into the LQ isn't enough and it's not keeping the LQ full of water?
I don't know that increasing the tubing size will help much, but it certainly won't hurt anything.

 

[Blowout]

The LQ is full. It's the flow rate from the LQ to the pump is reduced as indicated by the flow meter. Not enough chlorine from the LQ is getting sucked into the pump because of the lower backpressure. Adding backpressure by closing the bypass increases the flow rate. I end up regulating the LQ by opening up full the metering valve and adjusting by the bypass valve.

I tried removing both one way valves on the LQ lines and it did increase the flow rate. The problem is once the pump shuts down air gets sucked into the 2" lines and the filter system has to be primed again.

It seems the LQ function is dependent on the backpressure and not just the pump suction.

 

[crosley]

Let me know what you find, I would think it could help and wouldn't be difficult to add 1/2" lines to the system. The tricky part would be the openings inside the tank, I would think it would be difficult to modify the float opening.

Personally, I think there should be more of a "public service announcement" that the Liquidator just isn't a good fit with variable flow pumps. I thought I had found a silver bullet, but I find myself still having to manually add chlorine because it's just not adding enough despite the fact I've boosted my RPMs.

It probably works great with traditional, single speed pumps, but on variable flow where you use low speeds, it's just not getting the job done. It will probably be great the other 9 months of the year, but in the summer, it's just not cutting it.

 

[Bama Rambler]

The LQ is full. It's the flow rate from the LQ to the pump is reduced as indicated by the flow meter. Not enough chlorine from the LQ is getting sucked into the pump because of the lower backpressure. Adding backpressure by closing the bypass increases the flow rate. I end up regulating the LQ by opening up full the metering valve and adjusting by the bypass valve.

I tried removing both one way valves on the LQ lines and it did increase the flow rate. The problem is once the pump shuts down air gets sucked into the 2" lines and the filter system has to be primed again.

It seems the LQ function is dependent on the backpressure and not just the pump suction.

What you describe is exactly opposite of how the LQ works. By reducing the discharge head you increase the suction head a little and that's what makes the LQ work better. Inversely, by closing the bypass off a little you decrease the suction head and that would make the LQ flow less. Are you sure you have it hooked up correctly?

The only way what you described would make a difference is if there isn't enough discharge head to create enough flow into the LQ to keep it full and the outlet float valve is restricting the flow.

 

[Chuck_Davis]

I've got a head-scratcher of my own that might bear on this issue. Periodically I clean the suction-side tubing, flowmeter and check valve with dilute muriatic acid. After cleaning there is no change in the Liquidator flowmeter reading, but my chlorine level goes up dramatically. (Conversely, I'm realizing that over a period of months I was slowly increasing the flow to maintain the target chlorine level.)

If you haven't done so already, you might try cleaning the suction-side tubing, flowmeter and check valve. This might raise the chlorine feed level to where you don't have to fiddle with the bypass valve. I just posted a simple cleaning technique that can be done in seconds.