Chemtrol vs Rola-Chem Chemical Automation

[LeviStraussTx]

Does anyone have experience with Chemtrol chemical controllers, specifically the FAC sensor? Does it actually work, and is it accurate? I’ve gotten down to two options: Chemtrol 255 or Rola-Chem RC555XXP.

The Chemtrol actually measures FAC rather than ORP, but it’s almost twice the price ($3,300) and the sensor still has to be replaced every other year at a cost of ~$1500. It also is a “dumb” unit that is t connected to the internet and cannot be remotely monitored. The Rola-Chem is cheaper ($1,700), and it measures ORP then uses some algorithm to calculate FAC. It also has built in Ethernet (only hardwired), with free web access for remote monitoring.

I’m leaning towards the Rola-Chem due to cost, but looking for any insight on either one regarding accuracy, longevity, etc.

 

[cowboycasey]

For that kind of money just install a salt water generator and call it a day... You already have a salt water pool...

The only thing I have read about the ORP sensors is higher CYA tweaks them out and they do not work great...

 

[dschlic1]

Stay away from ORP. Good commercial chlorine probes should last a number of years. Municipal water and wastewater plants use them. They do need to be calibrated and there is a maintenance schedule associated with them.

 

[LeviStraussTx]

Thanks for the feedback. I’ll keep my ears open for any more inputs. I understand the limitations and variance associated with ORP. But, at the same time, those variables don’t change much over the course of the day, so ORP change is mainly associated with FAC level changes throughout the day. I’m thinking I may just buy an arduino based kit and play around with it for a bit first. I currently have a stenner pump setup on a ZWave switch and just run it on a half hour duty cycle for 8 hours. I’ve only had it running for a couple days, but I really like the idea of self adjusting day to day based on weather, bather load, etc. The ZWave is a good bit more intensive to adjust due to those factors, and I’m really looking for a more hands off type of set it and go system and I only need to really check it once a week or so.

 

[reggiehammond]

Your last few sentences describe a salt water chlorine generator perfectly!

 

[LeviStraussTx]

To clarify, I do not have a salt water pool. It is fresh water. If my profile says differently, can you point out how to change it?

 

[cowboycasey]

To clarify, I do not have a salt water pool. It is fresh water. If my profile says differently, can you point out how to change it?

Everyone has a salt water pool, I bet your salt content is already at 2000 ppm or more... Someone just changed over to SWG and there pool was at 4200 ppm salt.. Grab a salt test kit and see what you are at now, I bet you will be surprised

 

[LeviStraussTx]

I get what you’re saying now. I just did a complete drain and refill 2 weeks ago, so the water is quite pure right now. When I drained it, the water was the original fill from 2 years ago, and TDS was at 800. We wanted to do salt water at first, but the pool is only 3 feet from the house and we were strongly advised against it to avoid corrosion of Windows, doors, etc on the house.

I agree, a SWG does exactly what I’m looking for. I just can’t use one.

 

[cowboycasey]

Ahh, you do not have a salt water pool now but you did 2 weeks ago..

That is SWG scare tactics from Texas.. A salt water pool has about 3000 ppm salt, they are trying to say that a salt pool is the same as the ocean water at 35,000 ppm.. the ocean has WAY MORE SALT than a salt pool and can damage your house if you were 3 feet from the Ocean.. Nothing will happen to your house, windows or doors or anything on your house... They do not want you going to a SWG because you will no longer need to go to them and get your chemicals, then they will not be able to sell you stuff you do not need..

I do have some rust on metal parts on my Intex pool after 9 years but I doubt you have any metal parts in your pool not designed to be in your pool..

There are thousands of salt water pools with non damaged houses and pools in Texas, trust me...

 

[reggiehammond]

I recently helped a neighbor convert their liquid chlorine pool to SWCG as they were scared of the minor PVC work. It took less than an hour and we had to add TWO bags of salt to their ~20k gallon pool. It was already a salt pool, as cowboycasey points out.

 

[dschlic1]

The problem with ORP is that with CYA levels 30 ppm and above, the ORP level will not change even with a significant change in FC level. If you want to use ORP, then you must keep your CYA levels 20 ppm or lower.