At what temp will water begin to freeze damage plumbing ?

[Underwater Man]

This is the first winter with our newly renovated pool. It has the Polaris EOS Command Center with the freeze guard set to come on at 36 degrees air temp. or 34 degrees water temp. When the freeze guard activates it turns the pool and booster pump on for 15 minutes, then shuts down, turns the valves, then runs the spa for 15 minutes, alternating back and forth until the temp gets above 36 degrees. The blower to the spa runs for 5 minutes every half hour. I don't want to take any chances on damaging my plumbing, pumps etc, but 36 seems too high for activating the freeze guard. Last winter my filter was prone to blowing the seal, and since we had decided to renovate, I did not run the pump at night, or when I was away. Several times the temp dropped to the mid 20's with no apparent damage. I want to be safe, but don't care to cycle my equipment on and off so much before the temperature really requires it. Our Texas winters are pretty mild, but temps may hang between 36 and 32 for long periods of time. What's the lowest temp I can safely go before activating the freeze guard? All opinions or personal experiences will be greatly appreciated.

Thanks, Dan

 

[mas985]

I have a similar situation. When I first put the pool in, I had the freeze guard set to 38 degrees which would turn on quite often in the winter here, I lowered it to 33 degrees for a while and last year, I simply shut it off and now go without.

I can't give you an exact number as the lowest temperature without freeze guard but I know that it is well below 32 degrees. It is both temperature and duration of the temperature that will freeze the pipes. So even though it may go below 32 degrees, if it is only for an hour or two, it may be unlikely that the pipes will actually freeze solid.

A good test is to keep a bucket of water next to the pad at about 2" deep, and see if in the morning it is frozen solid. If not you are probably ok to turn off the freeze guard, if it is frozen, then I would keep the freeze guard on but at the lowest setting possible.

 

[Underwater Man]

Thanks Mark, I appreciate the info. I knew duration had a lot to do with it, and we will likely drop to 30 to 32 degrees for a few hours quite often. Those are the times I was hoping I could leave the freeze guard off. The bucket of water by the pad is a good idea. I'll do that every time temps 32 or lower are expected. That should be a good way to find the answer. I'll post my results back to this thread.

Thanks Again, Dan