Pool Pump Freeze Pretection


1) Give a description of the problem
Looking to add freeze protection to my pool pump for the winter months. I thought I had it setup up but since it was over 32 degrees F it kept turning off the pump in the summer months.

2) What is the expected behaviour?
I want the pool pump to run 8 hours per day during the spring and summer months and then over the fall and winter 3 hours per day. I do want it to kick on though when my outside temp drops below 30 degrees for more than a couple of hours and then back off once the temp hits above 32. I have an outdoor temp sensor I’ll be using to monitor the temp.

3) What is happening/not happening?
Since its higher than 32 degrees F it keeps shutting off

**4) Post a Green Snapshot of the piston![image|45x37]

5) Attach logs after turning logging level to Full
No logs as of now


Quick question,
How is it shutting OFF? There is nothing in your piston does that. (Temperature related OFF)


I took that part out of it as it was shutting of all the time. I had something in there that when below 30F for 1 hour turn on and then turn off once deck door rises to or higher than 34. Like an idiot I deleted that piston and started all over again and left it with my current times.


ı would say do this with two piston.
One is what you have, seasonal
And the second one is daily and temperature controlled.
(You can do it in a single piston but when there are timers involved, i prefer to leave that piston alone.)

IF outside sensor temp raises to or above 32
With outlet 3 
Do turn OFF

IF outside sensor temp drops to or below 30
With outlet 3 
Do turn ON

Here is the thing,
Lets say it’s 9.45 am and the piston is on timer to work for 3 hours. But outside is above 32 and your pump is working for no reason (I don’t know your area maybe this scenario is not even possible, weather never gets that warm in the morning)
Then you can add the temp as a condition to your original piston.

Every day at 9.30 but only this and that month
IF temp is 30 or below 
With outlet 3
Turn ON
Wait 3 hours
Turn OFF

Something like this.


I think I have it figured out. I did create a whole new piston for it. I still want it to run in the winter or at least 3 hours a day during the sunniest part to create movement and prevent algae, however still needed it to run anytime the temp drops below 30 for at least an hour to prevent possible freezing and shut back off again once over 33. I am in Georgia just outside Atlanta so we don’t get hard freezes often but its better to be safe than sorry. Also the pool is a salt system so that why I have it set to 30 for over Here is what I’ve come up with, let me know what you think.



1 - Always trigger first, conditions later…
Switch places 18-20
Switch places 32-35

2 - The way you use IF block within IF block will never execute (the second IF block) probably that was a mistake.

3 - And in second IF block - even if you use it seperated - will never execute because,
You are telling the piston execute IF
IF temp is less then or equal to 30
IF temp rises or above 33

you see what I mean…


agree with @ike2018. Your ‘when true’ should just be a ‘then’ and separate the second if.

The second if can be simplified to just the trigger as turning off when it is already off won’t hurt anything so whether it was less than 30 F or the outlet is currently on doesn’t really matter.


Thanks for your help, I really appreciate it. I did not notice the second IF block within the original IF. So If I’m reading this correctly now This Piston should turn the pump of when the temp drops below 30 for 1 hour. Unless its already running between its current run time of 12 and 3pm. Then If the Temp was below 30 for 1 hour and then rises to or above 33 it will shut the pump Off.


you are so welcome…

  • I don’t understand line 29 ??
  • And always trigger first condition later (line 29 line 31)


My thinking in that one is so it won’t shut off during its normal 3 hour cycle between 12P and 3P and already higher than 33 degrees, remember there’s another piston that’s triggering the pump to come on daily from 12 - 3p for algae prevention. This way the only time it would shut off higher than 33 is if it was originally triggered by the first part of this piston of being below 30 for 1 hour or more… Maybe I’m making it more complicated than it needs to be? I guess I could also use the time trigger too?


Your second if won’t stop it from turning off at say 1:30 PM. If it was less than 30 for over an hour and rose to 33 anytime after noon, it will shut off. Better to use the same time restriction you have in the first if to avoid turning off during that time. And put the trigger first.


Maybe you wrote that way by mistake but if you look at your swecond IF block,
it says,
IF contact 10 is less or equal to 30 for 1 hour
IF (Same contact) rises above 33
then execute

This will NEVER happen…
You are setting up a piston that will execute IF the weather is 30 and 33 at the same time…
you see my point?

If you get rid of line 29 I believe you’ll get the piston you want…