in-line automatic chlorine feeder does not put in enough

[gf]

I have IG pool with a erosion in-line chlorine feeder. It sis is full of tablets, the water is a warm 85 and still there is not enough chlorine according to the tests tripe afters days of running. Any idea what not. I am using the 3" tablets. The feeder is rated in size for our 20,000 gallon pool.

[BobK207]

Inline chlorinators frequently have flow problems.

The chlorinator has to "steal" some of the water from the return flow, use it to errode the tablets & reintroduce the chlorline laden water back into the return flow at some point "downstream".

If you get too much prssure drop in the unit there's not enough pressure to force the chlorinated water back into the return flow.

Additionally a gas pocket can form that prevents wetting of the entire tablet stack.thus reducing the output of the chlorinator.

An offline chlorinator takes water from upstream of the filter, runs it through the chlorinator & reintroduces the chlorinated water back into the return flow at some point downstream. In this arrangement there will always be plenty of pressure available to inject the chlorinated water back into the return flow.

An offline chloriantor might be a little more work to install but I'll but they work more reliably than the offline units..

cheers Bob

[John]

Need more info like other readings (Ph, alkalinity, stabilizer-cyanuric acid), condition of water Is your pool in all day sun? That eats chlorine like crazy. Also, the chlorinator is made to maintain Cl levels, you may need to use bleach or shock to get the level up, then let the chlorinator maintian that level but even then, wihtou the correct evel of stabilizer, the chlorine will go t the sun. At 85 F and a low Ph, your pool might be right on the verge of exploding with algea and the chlorine is using all of itself just to keep the algae in check You can Bob's advice and move the return line for the chlorinator to the water return line AFTER the filter or you can stick some of the tabs in the skimmer and see if that helps. Last point, get rid of the strips, use a dropper test kit or better yet, get one that can test for total and available Cl.

[Richard J Kinch]

I can't imagine this could possibly dose enough chlorine for a sunlit pool.

[BobK207]

John-

Good post....I should mentioned the the issues rather just concentrating on the chlorinator.

so here goes

OP- some general comments

85F is pretty warm those test strips are OK but have good mulit-test kit as a backup / double check what is chlorine demand? pool usage (number of people, etc), organics, debris how long does the filter run? when was the chlorinator installed? ie when did you make the switch from manual to automatic? did it ever work?

try bringing up the Cl level with dry chlorine (or crush up some tablets) & see if the inline unit can maintain it.

Also as John mentioned water chemistry is very important

but I assume everything was working fine with a floater or tabs in the skimmer (btw not so good for copper plumbing or filter components; BTDT :( )

and you just swithced over to automatic?

If this is the case the inline system is probably the problem.

cheers Bob