Any risk in running pump in 10 degree weather without a heater?

I spent Saturday afternoon putting blankets and tarps over my equipment pad. Been running the equipment continuously since Thursday. Now I’m second-guessing my decision and wonder if I should just drain the equipment. What are the cons associated with draining the filter and pump? Seems like it would give me peace of mind over the next five days. I’m in Waco TX and we will be in teens, single digits, down to zero, and then climb to low twenties through next Friday. I’m worrying myself to death over this.
 
Well, no looking back from here. Have a couple of heavy drop cloths I might add over equipment later, but 25 outside, water temp 38 in Dallas. Pentair freeze protection running 24/7 Pool/Spa. Will see where this takes us over the next 6 days.
 
This article has been mentioned several times in this thread. If you continuously run your heater in cold water you it will start to corrode and you will void the warranty.


It should be pretty easy to turn your heater off in spa mode. Here is what mine looks like in the Pentair Intellicenter, so Easy Touch should be similar:

1613313084048.png
 
ajw22 said:
The Pentair MasterTemp Heaters say:
  • Operating this heater continuously at water temperatures below 68° F. (20° C) will cause harmful condensation and will damage the heater and void the warranty.
  • When starting the heater for the swimming season with a water temperature below 50° F (10° C), the heater may be used to heat the water; however, make sure that the heater operates continuously until the water temperature reaches the heater’s minimum setting of 68° F (20° C).
The Hayward H-Series heaters[say "Do not use the heater to maintain the water temperature just above freezing or for freeze protection."

Heater Condensation - Further Reading

www.troublefreepool.com
Click to expand...


Here is one of the references from AJW, also with verbiage from the heater manufacturers. You do not want it to cycle from pool mode (heater off) to spa mode (heater on) in this weather since your heater will be turning on and off and cause the condensation mentioned above.
 
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I’m going to go ahead and put a jug in the skimmers. My optimism is waning and it’ll be too late once it’s frozen. Assuming empty, rocks in the bottom but lid off so air isn’t trapped and jug can’t crush. Is that correct?
 
Either way, lid on or off will work. You’ll probably have to fill it halfway with water.

also, make sure to keep your skimmer basket in, if any rocks somehow escape.
 
Here is one of the references from AJW, also with verbiage from the heater manufacturers. You do not want it to cycle from pool mode (heater off) to spa mode (heater on) in this weather since your heater will be turning on and off and cause the condensation mentioned above.

Like I said earlier, I've read the whole thread. I've seen all the confusing talk about heaters and condensation. I thought the conclusion was, that if you're going to turn the heater on, make sure to leave it ON until the water temp in the Spa gets above 68, before turning it off.

If we were never supposed to turn a pool heater on if the water temp is below 68, then are you and the heater manufacturers saying nobody should ever use their Spa if the water is below 68?!? That would render a lot of heaters and Spas pretty useless for a lot of the year, no?
 
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@Poolmama! can you explain what the jugs in the skimmer will do? We’ve only had our pool since Labor Day and are still learning. If there’s anything I can do to prevent damage I’ll do it.
 

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I’m going to try and answer multiple questions here in one post,

@nikausp You’ll want to avoid trying to heat the pool as it’s just going to take so much time. Spa’s are a very small body of water and they simply don’t take long to heat up. Here’s an article further explaining

@Green25. Placing a water bottle filled with pool (or RV) antifreeze into the skimmer will create a “weakpoint” on purpose. The water bottle will allow the ice to expand and crush the bottle rather than the ice crushing the skimmer. A torn-up pool noodle works as well.
 
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Here is one of the references from AJW, also with verbiage from the heater manufacturers. You do not want it to cycle from pool mode (heater off) to spa mode (heater on) in this weather since your heater will be turning on and off and cause the condensation mentioned above.


To be clear, a pool heater running with the water temperature below around 60 degrees creates corrosive condensation. One run from a cold water state to get the water above 68F and then maintaining the water at 68F or above will not cause enough corrosive condensation to damage the heater. The question will be with the cold air temperatures and your pool volume if your heater can get the water temperature above 68 in a reasonable time.

What will damage your heater is setting the heater thermostat below 68 and letting it cycle and maintain a low water temperature to save on your gas bill. That will continuously create corrosive condensation on every heater cycle.

Spas get to temperature quickly and don't create the problem. Pool volume is much greater then a spa and you will be creating corrosive condensation until the water is past around 68F.
 
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Like I said earlier, I've read the whole thread. I've seen all the confusing talk about heaters and condensation. I thought the conclusion was, that if you're going to turn the heater on, make sure to leave it ON until the water temp in the Spa gets above 68, before turning it off.

If we were never supposed to turn a pool heater on if the water temp is below 68, then are you and the heater manufacturers saying nobody should ever use their Spa if the water is below 68?!? That would render a lot of heaters and Spas pretty useless for a lot of the year, no?

Keep in mind that your freeze protection will be cycling between pool and spa modes. If you just have the spa on in heater mode, the heater will be cycling on/off ever 15 minutes which is bad. I guess you could turn both pool and spa heating modes on, so it stays on constantly, but I would worry that you will quickly reach a point where your spa is at temp and your pool is not, and you return to cycling on/off.

Houston is not supposed to get below freezing and stay below freezing like the rest of the state, so I would not risk messing up my heater. Our pools in Dallas handle freezing temps in the 20's and sometimes upper teens on a regular basis just fine using the freeze protection.
 
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Like I said earlier, I've read the whole thread. I've seen all the confusing talk about heaters and condensation. I thought the conclusion was, that if you're going to turn the heater on, make sure to leave it ON until the water temp in the Spa gets above 68, before turning it off.

If we were never supposed to turn a pool heater on if the water temp is below 68, then are you and the heater manufacturers saying nobody should ever use their Spa if the water is below 68?!? That would render a lot of heaters and Spas pretty useless for a lot of the year, no?

The issue is if you STOP using the heater before the water gets to a temperature of about 68 degrees. My heater is well over 10 years old and I use it often during the winter (no hot tub, just the pool) and so far...no issues. As a matter of fact, I started mine yesterday and it's now almost 80 degrees in the pool while it is 6 degrees outside. So, it *can* be used, but there are risks...so you will have to evaluate the pros/cons. Do a search for "heater freeze" in the search box...you will get lots of results.
 
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@Leebo Thank you for explaining! We don’t have any pool antifreeze, but TFP and its users are a wealth of information to a new pool owner.

Sorry for the 20 questions, but does the pool noodle method just consist of cutting off the end and stuffing into the skimmer basket?
 
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I’m going to try and answer multiple questions here in one post,

@nikausp You’ll want to avoid trying to heat the pool as it’s just going to take so much time. Spa’s are a very small body of water and they simply don’t take long to heat up. Here’s an article further explaining

@Green25. Placing a water bottle filled with pool (or RV) antifreeze into the skimmer will create a “weakpoint” on purpose. The water bottle will allow the ice to expand and crush the bottle rather than the ice crushing the skimmer. A torn-up pool noodle works as well.

I've mentioned trying to heat the spa in Spa mode. I haven't mentioned trying to heat the entire pool.

What leads to my confusion...
I read in this very thread , conflicting info:

1. it's ok to use the heater for the Spa even if the water is below 68, just make sure to take it at least above 68F with the heater.

2. Don't turn the heater on for your Spa if the water temp is below 68.

🤔🤔🤔
 
As a matter of fact, I started mine yesterday and it's now almost 80 degrees in the pool while it is 6 degrees outside. So, it *can* be used, but there are risks...so you will have to evaluate the pros/cons. Do a search for "heater freeze" in the search box...you will get lots of results.

It all depends on the heater BTU, pool volume, and temperatures involved.

14K pool with 400K BTU gas heater gives a lot of heat to a smallish pool.
 

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