Stenner Injection check valve issues??

[CHSRpool]

I am running sodium chloride to my pool with stenner peristaltic pump, which enters my return line via stenner inject check valve. Seen here: http://www.uswatersystems.com/stenn...=10&fep=2221&gclid=CI-t3-rbs8cCFQIQaQodmOgDYw

I have occasionally had to replace parts in the pump and lines but never had any issue with the inject valve that feeds the chlorine into the plumbing. I have been troubleshooting for a few days now and had the following observations.

1. The pump itself is working normal, the line puts out chlorine.
2. When the line is detached from the inject check valve, there seems to be a strong stream of water coming back out the inject check valve
3. After taking the check valve out of the plumbing and attaching the chlorine line I clearly get chlorine dripping through the inject check valve.
4. When running the chlorine pump with the chlorine line hooked to the check valve in return plumbing it seems as though water pressure is pushing back through the check valve not letting the chlorine into the line.

I thought it may be a chemistry issue and the chlorine wont hold but nothing looks to bad
FC .2 TC 1.2 PH 7.6 ALK 160 CYA 18 CH 71...Indoor SWP

I have ordered new stenner inject check valve to replace that, hoping that is my issue.

Thanks for the help!!

 

[Bama Rambler]

I hate to tell you, but I seriously doubt that the check valve is your problem. If you remove the check valve completely the pump will still pump bleach into the system. The check valve is only there to prevent backflow from the pool in case the tubing breaks or comes loose.

What is the filter pressure?
Which pump do you have?
How is the pump controlled (timer, ORP, etc.)?
If by timer, how long is it running per day?

When was the last time you changed the pump tube?
Are the rollers pressing against the tubing tightly?

 

[CHSRpool]

I am running pentair intelliflo multi speed pump, filter reads 36 PSI. I run the pump 24/7 its a commercial play pool. Occasionally the pump will stop and reset but is usually always running. I know i have flow running through the return, I have a salt cell in the plumbing after the filter before the site where the chlorine enters the line. The salt cell has a flow meter and shows flow. I changed the pump tube about 4-5 months ago, I can replace and see if that helps? If there is chlorine coming out the line the pump is working correctly right? If indeed the chlorine is entering the return line I just dont know how its possible to keep getting these low FC readings. I was thinking it may be the low CYA level but its indoor salt pool so doubt that..

 

[Bama Rambler]

It honestly sounds like you have something consuming the FC.

If the pump tube is collapsed or the roller compression springs are weak, it will put out some bleach, but it won't overcome much pressure. You can put your gloved thumb over the tubing while it's running and if you wait a little while you shouldn't be able to stop the flow out of the tubing.

Now answer these questions about the Stenner pump.

Which pump do you have?
If it's ran on a timer, how long is it running per day?
Are the rollers pressing against the tubing tightly?

 

[CHSRpool]

I am leaning toward something must be consuming the FC as well. I have the same set up going to indoor tubs as well and I switched over the pool line to the hot tub line and vice versa. When hooking the pool chlorine to the indoor tub the FC began rising, when putting the indoor tub CHL line on the pool still no big gain in FC in the pool. The FC went from .8-1.0 but will not rise much even when i manually run it for an hour or so.

1. 45m2 Stenner classic single head peristaltic adjustable chem pumps
2. Not run on timer, manually turned on/off
3. I replaced the tubing and rollers are tight against.

As I mentioned above I replaced the tubing so I am currently checking to see if that will help. I usually can quickly figure out whats going on but this one is stumping me, thanks for the help.

 

[Bama Rambler]

I'd lean more toward something consuming the FC instead of an injection pump issue.

If you could run an OCLT on it, that would tell you if it's organics. However, I realize it may not be feasible in your situation.

 

[tim5055]

Your original testing points me to something consuming the chlorine. .2 FC and 1.2 TC tells me you have 1.0 CC.

What are you using for testing that you get 18 CYA?

 

[CHSRpool]

So I ended up bringing the chlorine level up by slightly shocking last night with liquichlor, also replaced the tube in the pump. This morning I turned on the pump and am now seeing a normal change in FC when it is running. So not sure it if was a bad luck combination of the tube going bad and something eating my FC or what. Also I did not see anything wrong with the tube I changed out. It seems odd to me that the tube would be bad and still put out a constant drip when i checked the line??? Anyway thanks for all the input, pool looks nice since I replaced sand and chemistry looks good.

I use the LaMotte Color Q test kit, it seems pretty accurate.

 

[tim5055]

I use the LaMotte Color Q test kit, it seems pretty accurate.

Please do not confuse the sepecificity of the numbers being given with accuracy. What is the comparison to say "it seems pretty accurate"?

We have had numerous people attempt to use the Color Q and almost all of them abandoned it within a relatively short period of time.

The last one I remember abandoned it after about a month because testing the same water sample three times in a row provided three different results. For the sake of your pool water please compare it's results to tests provided by Taylor reagents on a regular basis to verify you are still getting accurate results.

Some of the most inaccurate pool store testing I have seen personally was provided by the commercial version of the Color Q, the LaMotte Waterlink Spin Lab. WaterLink Spin Lab - 3576 - Pool and Spa - LaMotte