Salt Water Chlorinator

[blackadder]

In September I purchased a new salt water chlorinator which had received great reviews. It has a salt level function which as stated is a guide only.
After two months of it working faultlessly, it suddenly started showing "check salt". It is designed to operate as low as 3500ppm and up to 6000ppm. A test from the pool shop showed 4500ppm. It was then that I noticed that the cell was showing quite a lot of calcium build up despite being a self cleaning unit. So I cleaned it, and the salt level came up to roughly where it should be.
Within a few hours of operation, it was reading low again (under 2500ppm).
The problem with the salt reading is that if it thinks the salt is low, it won't give full chlorine output.
After contacting the manufacturers, I sent the unit back for repair. They now inform me that it is something in my water which is coating the electrodes and causing false salt readings and causing calcium build up. Possibly body oil, suntan lotion or algaecide.
Given that the unit worked without a problem for two months, and then played up I am sceptical of their claims because the pool wasn't in use during that time (too cold), and is covered with a blanket.
My previous two chlorinators never suffered the same issue, and I feel that I am being "dudded". The machine cost a lot of money.
What is the opinion of other member?

[Denniswiseman]

It could be you have a large build up of calcium in your pool
How are you testing?

[blackadder]

Hi Dennis. I take a sample to the pool shop about monthly. In the meantime I check with test strips.

[Denniswiseman]

Test strips are commonly called guess strips
You really need to get yourself a decent FAS/DPD test kit (Taylor K2006c or TF Testkits TF100 in the states) to get accurate results as maintaining an appropiate shock level means testing quite often during the day and not just dumping shock in and thinking "that's it"
You've already invested in an expensive SWCG invest a bit more in a test kit. You can check all your levels when ever you need to

[blackadder]

Pool shop testing is no good?

[Denniswiseman]

Pool shop testing is no good?

It's only as good as the person doing it and when you have algae or combined chlorine you have to Slam (Shock Level and Maintain) testing frequently during the day
Any serious pool person has a test kit

[blackadder]

At the moment I don't have algae or combined chlorine.
I am interested to know whether the salt reading on my chlorinator can be affected by sunscreen, algaecide, or other impurities.

[Denniswiseman]

What is your calcium level in the pool

[blackadder]

Calcium hardness is 255, and has slowly been reducing over the last two months from 294.

[Denniswiseman]

That level is OK
I've never heard about oil or algaecide causing a problem with SWCG especially as it's to cold at the moment
Have you cleaned it again

[blackadder]

It's at the workshop being tested. They claim its fine and the reason it is reading incorrect salt levels is down to my pool water

[Teapot1]

Then let them tell you what's in the pool water affecting the chlorinator. If they can't then they are making it up (Lying)

[Denniswiseman]

Give them a complete list of the poolshop testing results to show them, so they can tell you what's wrong

[Teapot1]

Agreed but pool shops only test for the usual common things, also what equipment does the shop use? Dip strips like a lot do in France or a spin test which is pretty good. If the chlorinator is failing due to an uncommon polutant, let them tell you what it is.

[blackadder]

A follow up to my original post - the manufacturers have agreed to replace my chlorinator with a new unit. They advise that the old unit was working 100% after they cleaned it, but in the interests of customer satisfaction, they have agreed to replace it.
Initially, they were intending to return the old unit, but I made a huge fuss which prompted a change of heart on their part.