Preparing for next time

[dailygenesis]

Well, I think we made it through our first big freeze mostly unscathed. In some ways, I'm glad to have gone through this as I learned a lot. That said, I wish we could simply never have freezing temps again.

But alas, I'm trying to learn from this experience and prepare better for next time. Here is one issue that I've been pondering since the big event. I'm wondering if anyone has any insight on this.

Our approach this time was to keep pool equipment running (pool and spa are uncovered and open). This worked fairly well since we never lost power. By running the pool equipment constantly, we kept the pool temps evenly distributed throughout the water. This was great at the beginning when the original water temp was around 42 so the colder surface water got mixed in with the warmer water below and kept things from freezing.

But, as time went on, water temps went down. We got all the way down to 32 degrees in the water where things seemed to pin and stay pretty steady. At this point, I'm thinking that all of the water in the whole system (pool surface, bottom of pool, in the underground pipes, etc.) is now right on the verge of freezing. If we had lost power or equipment had frozen up at this point, it seems that it would be very easy for all the water to freeze pretty quickly. It seems this would be true even underground where it generally wouldn't get that cold, but we had brought the temps in that underground water down by running the equipment (maybe the warmth in the ground would continue to help at this point, but it just didn't seem great to have 32 degree water in the underground pipes).

So, one thing I thought that might mitigate the above would be to pre-heat the entire pool to 70+ degrees in advance of the weather moving in. I have read a few posts of people doing this and it seems to have helped keep their water temps well above freezing throughout the event. Obviously, there's a limit to this as, eventually, the water will get down to 32 degrees if the weather persists long enough, but it would certainly delay hitting the freezing point and allow the running equipment to have a positive effect of keeping warmer water flowing.

Another approach, though, is what is discussed in this thread - The Physics of Freezing and Freeze Protection - by @mas985

The thesis of that thread appears to be that running the pumps constantly during freeze events isn't the best approach (or at least not the only approach). Rather, if freezing weather is mild enough, you can just do nothing, and if it's more severe, you can drain the equipment and let the system go idle and open everything up enough to give the water room to expand as it freezes.

But my question to @mas985 or anyone else is -- are you saying this approach (drain the equipment and let it go idle -- without fully winterizing or blowing out the pipes) can work even through extreme weather events like what we just experienced? I see the logic in it, but I would also expect that would result in a whole bunch of frozen water -- across the entire pool surface, in the skimmer, in all pipes above ground and extending at least some amount underground, etc. Is the thesis of the above article intended for severe events like this one or just for more mild freezes?

 

[Newdude]

At this point, I'm thinking that all of the water in the whole system (pool surface, bottom of pool, in the underground pipes, etc.) is now right on the verge of freezing. If we had lost power or equipment had frozen up at this point, it seems that it would be very easy for all the water to freeze pretty quickly. It seems this would be true even underground where it generally wouldn't get that cold

Such is the gamble with this. If you've successfully kept the water moving, it may be in the low 20s when the power goes out or something else derails the plan. Then you have very cold water which will freeze far quicker than water near 32 degrees. Instead of taking hours or days, it can happen in minutes.

this approach (drain the equipment and let it go idle -- without fully winterizing or blowing out the pipes) can work even through extreme weather events like what we just experienced? I see the logic in it, but I would also expect that would result in a whole bunch of frozen water -- across the entire pool surface, in the skimmer, in all pipes above ground and extending at least some amount underground, etc

The hope is that by fully draining all above ground plumbing and equipment, that the ground delays underground freezing long enough to make it through the event. A week would (hopefully) be long enough to stay in the clear which would cover most events. If you guys get hit with an event that lasts weeks, then you'd need to blow out the plumbing. But also hopefully, there would be some warning that such an extended event was coming.

As we get through more rodeos and learn from them, I now want folks to make pipe adaptors for their returns and skimmers. If the time came that they wanted to pull the plug, they could screw in the extenders like a blow through gizmo for the skimmers and an L shaped pipe for the returns. The water level wouldn't need to be drained yet the pipes could be blown with a large shop vac, and antifreeze added at both sides for insurance if any water was left in the pipes.

For anyone staying open and presumably closing in haste, it would be a reasonable back up plan. With a dry run performed in nice weather, it would be easy to repeat when time was of the essence. It would also be easily reversible when the next few weeks were in the 70s again. Simply remove the adapters, flood the system and fire it up.

 

[ajw22]

Closing a pool can be done in an hour or two if you know your way around the pool and equipment an have the plugs, pump, and blower.

I sit in the Northeast with my pool closed for the winter and watch the stress and damage that pool owners go through in the South when a cold blast is predicted. I don't understand why you want to go through that when you can spend an hour or two before the cold hits and flip off the breakers, lower the water level, pull the drain plugs, put a blower on some lines, put plugs in skimmer and returns, and then relax and stay nice and warm through the cold spell.

Getting the pool running again should take maybe an hour.

I don't get the reluctance of shutting down the pool before freezing spells.

 

[dailygenesis]

Closing a pool can be done in an hour or two if you know your way around the pool and equipment an have the plugs, pump, and blower.

I sit in the Northeast with my pool closed for the winter and watch the stress and damage that pool owners go through in the South when a cold blast is predicted. I don't understand why you want to go through that when you can spend an hour or two before the cold hits and flip off the breakers, lower the water level, pull the drain plugs, put a blower on some lines, put plugs in skimmer and returns, and then relax and stay nice and warm through the cold spell.

Getting the pool running again should take maybe an hour.

I don't get the reluctance of shutting down the pool before freezing spells.

Ok so this idea of closing / opening the pool before / after each individual event is new to me. I was sort of assuming if you "closed" the pool it was for the whole winter or at least for longer term. Where I can I read about the equipment and procedures needed to do this kind of quick shut down and start up? Also, is this a practical approach if one doesn't have a pool cover? What about the ice that will inevitably form on the surface?

 

[mas985]

One thing that many seem to forget is water does not freeze the instant that air temperatures drop to 32F. In fact, it will probably never freeze at that temperature. The latent heat fusion dictates that a lot of heat must be removed from the water before it even starts to freeze. So you need temperatures well below 32F and for many hours. This sticky shows the relationship:

The Physics of Freezing and Freeze Protection

Recently, there have been a lot of questions from those living in moderate climates about using automatic freeze protection or running pumps to prevent freezing and what a pool owner should do when temperatures drop so I thought it might be useful to have a thread which dealt with the issue from...

www.troublefreepool.com

But my question to @mas985 or anyone else is -- are you saying this approach (drain the equipment and let it go idle -- without fully winterizing or blowing out the pipes) can work even through extreme weather events like what we just experienced? I see the logic in it, but I would also expect that would result in a whole bunch of frozen water -- across the entire pool surface, in the skimmer, in all pipes above ground and extending at least some amount underground, etc. Is the thesis of the above article intended for severe events like this one or just for more mild freezes?

As the thread shows, it takes some time for water to freeze. It depends on the the air temperature, the time below freezing and wind speed. But in general, for plumbing 1.5" or larger, it is very unlikely to freeze if air temperatures do not remain well BELOW freezing for less than 8 hours. For the pool water to even start to freeze, it will take many days of sub 32F temperatures. How long again depends on the temperature profile.

As I have mentioned in the thread and many other threads, we get below 32F many times during winter and sometimes down to 26F and I never use freeze protection and nothing other than a shade sail over the equipment and have never experienced any freezing of the pipes. But I have very high confidence that it won't based upon the analysis and measurements that I did.

Each individual pool owner should do their own risk assessment but from what I have seen on the forum and the extent that many go to avoid freezing, some are overreacting to the conditions that they are experiencing while some are perhaps underreacting by relying too much on just pump run time for freeze protection. That was the point of this thread.

 

[dailygenesis]

As I have mentioned in the thread and many other threads, we get below 32F many times during winter and sometimes down to 26F and I never use freeze protection and nothing other than a shade sail over the equipment and have never experienced any freezing of the pipes. But I have very high confidence that it won't based upon the analysis and measurements that I did.

Each individual pool owner should do their own risk assessment but from what I have seen on the forum and the extent that many go to avoid freezing, some are overreacting to the conditions that they are experiencing while some are perhaps underreacting by relying too much on just pump run time for freeze protection. That was the point of this thread.

Understood, but I guess I am talking about events like we just had where air temperatures were in the single digits for multiple days and sub freezing for 3-4 days. They way I read your thread it was saying that in mild freezes, you can get by with doing nothing, but for more dramatic freezes you can drain the equipment and let things go idle. My question is that with an event like describe above, is draining the equipment and letting it go idle enough? Or would one need to blow out the lines, etc., and take more steps to "close" the pool?

 

[Newdude]

My question is that with an event like describe above, is draining the equipment and letting it go idle enough? Or would one need to blow out the lines, etc., and take more steps to "close" the pool?

That's the million dollar question and with no two events being the same, it remains a big fat question mark.

You either close for the season, or need to be able to adapt on the fly if the situation presents itself. The next freeze may be minor. The one after that could be much worse and last weeks. Historically it's a rare occurrence to need extra preparations besides simply running the system, but it appears we are in a cold cycle and it's been a topic of late.

Familiarize yourself with your system and how to drain/blow it if ever needed. I just got a new pool and having closed pools before, it took 30 mins to do, even with a new setup.

Hack Murphy's law to work in your favor. If you have the tools and skills at your ready, you'll never need them.

 

[ajw22]

Ok so this idea of closing / opening the pool before / after each individual event is new to me. I was sort of assuming if you "closed" the pool it was for the whole winter or at least for longer term.

As I said the basics of "closing" a pool can be done in an hour or two.

I have a heavy solid pool cover that alone can take an hour to put on or take off and store.

If it was not for my pool cover I could get my pool running in an hour.

Where I can I read about the equipment and procedures needed to do this kind of quick shut down and start up?

Every pool is different. And let me say here for everyone reading this that there are differences in how you handle a plaster pool, a liner pool, a fiberglass pool, and above ground pools. So we cannot give a simple one size fits all set of directions.

Take the directions in these links and figure out what works for your pool and run it by us here...

Closing Pool for Winter - Further Reading

www.troublefreepool.com

Closing an In Ground Pool

Winterizing a pool is essential for keeping your in-ground pool protected during cold-weather months. This Pool Repair guide will show you how to do it.

www.troublefreepool.com

Opening your pool- An easy to follow guide

Opening your pool can be stressful. This Pool Start Up guide teaches everything from start-up chemicals, covers, and more for your start up.

www.troublefreepool.com

Closing (Winterizing) Your Above Ground Pool

Closing an above ground pool at season’s end should be a fast and worry-free process. Learn the basics of above ground pool winterization in easy steps.

www.troublefreepool.com

I gave you the basic process in my first post...

...flip off the breakers, lower the water level, pull the drain plugs, put a blower on some lines, put plugs in skimmer and returns, and then relax and stay nice and warm through the cold spell.

Also, is this a practical approach if one doesn't have a pool cover?

There is no requirement for a pool cover other then it keeps your water cleaner and gives you less of a cleanup when you open the pool.

What about the ice that will inevitably form on the surface?

Depends on the type of pool you have. @Newdude pipe adapters technique is fine for liner pools where you do not have a tile line to protect.

I now want folks to make pipe adaptors for their returns and skimmers. If the time came that they wanted to pull the plug, they could screw in the extenders like a blow through gizmo for the skimmers and an L shaped pipe for the returns. The water level wouldn't need to be drained yet the pipes could be blown with a large shop vac, and antifreeze added at both sides for insurance if any water was left in the pipes.

For plaster pools you need to drain down below the tile line so that ice does not loosen or pop off tiles.

Once the water level is below the tile line and not right on any steps or ledges you are fine. Let the ice form then melt. That is what happens with all the closed pools here in the North.

Plan it out, gather the necessary equipment, and maybe even do a closing and opening for training purposes when it is warm and you will be prepared to close down your pool and relax in the winters ahead.

 

[Texas Splash]

My question is that with an event like describe above, is draining the equipment and letting it go idle enough? Or would one need to blow out the lines, etc., and take more steps to "close" the pool?

In regards to the pad itself, that's about it. Once everything is drained well, there's not much else to do in that area. If you don't lower the pool's water level below the skimmer, I would protect it with some pieces of pool noodle or a half-filled jug. Also protect any other potential locations (i.e. scuppers, fountains, etc) to be safe.

The need to go a step further like they do up north and blow out the lines can vary based on how your plumbing was installed, the anticipated length of freezing weather, and the frost line in your area. For example, I'm fairly confident in my area I could let the water sit still for days or weeks and be fine, however I would assume in your area the frost line goes deeper so you may need to take more precautions closer to the surface. Even the need to actually lower the water level depends on things like type of pool, expected accumulation of rain/snow, waterline tile, coping, etc. All of these things come into play that over time we learn to adjust to.

It's not unusual to have some cold spells, but we've had a couple odd years recently. Below are pics from 2017 (few days), then the big freeze last year in Feb '21 (over a week), now this one. My pump runs 24/7 as it always does with a cover at the pad. I've done well so far (knock knock) but I try to be prepared either way. As time goes on, you will adjust as well.

 

[ajw22]

If you don't lower the pool's water level below the skimmer...

Pat, I have to point out to all the readers that you have a fiberglass pool and lowering the water level is not just not required but not advised.

@dailygenesis , the OP, has a plaster pool with tile. Lowering the water level is necessary to protect his tile from ice loosening them or popping them off.

 

[mas985]

Understood, but I guess I am talking about events like we just had where air temperatures were in the single digits for multiple days and sub freezing for 3-4 days. They way I read your thread it was saying that in mild freezes, you can get by with doing nothing, but for more dramatic freezes you can drain the equipment and let things go idle. My question is that with an event like describe above, is draining the equipment and letting it go idle enough? Or would one need to blow out the lines, etc., and take more steps to "close" the pool?

Again, it depends on the average temperature and the number of days. But even if the pool starts to freeze, the pipes underground are going to be protected for much much longer because of the insulating effect of the earth not to mention it is also a heat source. Basically, you have until the frost depth gets to the pipes which usually requires weeks of sub-freezing temps.

The best advice in this particular case is that if you start to see ice form on the pool, then start to think about a full winterizing. But I would not expect you to ever see ice form on the pool (in 3 days). That would take many more days if not weeks.

Also, forgot to mention that a frozen pipe does not mean a pipe that is compromised. Pipes will only burst when the ice expands and the pressure has no where to go. Leave all valves open (check included) and the pipes should be ok even if they do freeze. Most damage is caused near a closed valve.

 

[dailygenesis]

But I would not expect you to ever see ice form on the pool. That would take many days if not weeks.

I guess I don't understand this part. We had ice forming on our pool last weekend within 36 hours of the event starting, and that was with pump running 24/7.

 

[ajw22]

The frost line of OK is 7 to 10" deep.

Any pipes in the ground below that level will not freeze. You only need to reduce the water level of the pipes by that much that come out of the ground at the equipment pad. If your equipment pad is at or above the water level then draining the pool by 7 to 10" will lower the water level in the pipes after draining the equipment.

 

[mas985]

I guess I don't understand this part. We had ice forming on our pool last weekend within 36 hours of the event starting, and that was with pump running 24/7.

Then you must of had previous days of freezing that you are not including in the 3 days mentioned. What was the low temperature during that period?

 

[dailygenesis]

Then you must of had previous days of freezing that you are not including in the 3 days mentioned. What was the low temperature during that period?

Here are the temps for the month of December. Things were pretty much above freezing most of the month (a few dips below here and there), but then at 4am on December 22nd, we plummeted to single digits with 30-50 MPH winds. My water temp was at 42 degrees when that system hit. About 1.5 days later, water temp was at 32 and ice was forming on pool surface. By the 24th, it was sunny and hitting near 32. On the 25th, we were back above freezing and everything thawed.

 

[JoyfulNoise]

Since Texas seems to get these intense cold snaps periodically, I wouldn't suggest the "pump and pray" method of freeze protection. Just open up all the drains (pump, heater, filter, etc) and open up all the valves or remove the covers on the various diverter valves and let all of the water out of your system. Throw a heavy painters tarp over the equipment and put a warm 60W lamp under the tarp. The water in the pipes will drain down to the level of the pool (that would be a few inches in my case). In that scenario, there is almost no chance of anything getting damaged. As Mark pointed out, it takes several day for water out in the open to freeze up and any water in pipes underground will take weeks to freeze.

You can leave a pool stagnant in the winter time for many many days before you would lose enough chlorine for there to be an issue. Even then, water that is close to freezing temperature will not be hospitable at all to algae growth. So there is no concern about sanitation.

Then, when the air temps come back to normal, just start it all up again. Playing games with running pumps when the temperatures plunge is Russian roulette. Just empty the equipment and go inside where it's warm.

 

[mas985]

Here are the temps for the month of December. Things were pretty much above freezing most of the month (a few dips below here and there), but then at 4am on December 22nd, we plummeted to single digits with 30-50 MPH winds. My water temp was at 42 degrees when that system hit. About 1.5 days later, water temp was at 32 and ice was forming on pool surface. By the 24th, it was sunny and hitting near 32. On the 25th, we were back above freezing and everything thawed.

View attachment 466879

Was the pump running the entire time?

Was ice forming in both the pool and spa? How much? Where was it forming?

 

[6XSBChamps]

Is there a link to videos on blowing the lines out? I see some that are as simple as running a blower from the pump basket blowing the air in reverse of how the water would be coming in from the skimmers. Is it as simple as that?

 

[ajw22]

Is there a link to videos on blowing the lines out? I see some that are as simple as running a blower from the pump basket blowing the air in reverse of how the water would be coming in from the skimmers. Is it as simple as that?

Pools are plumbed many different ways. There is no one simple way.

It depends on the power of the blower you use, where you can get access to the pipes with the fewest restrictions, if you are above or below the water level, how the pipes are run.

It sometimes takes trial and error to find what works best for a pool.

 

[dailygenesis]

Was the pump running the entire time?

Was ice forming in both the pool and spa? How much? Where was it forming?

Yes, the pump was running constantly through all the pipes, pool and spa.

As soon as the temps dropped that Thursday AM and the winds from the north blew in, ice started forming around the edge of the south end of the pool. Over the next 36 hours some ice build up around the edges of both the pool and spa, but nothing too concerning. The water was super choppy due to wind so not much chance to freeze solid.

During the second night, though, after water temps had come down to 32 and the winds had died down, a solid ice sheet started developing across the deep end of the pool. The spa was in good shape probably due to the constantly swirling water. In the pool, I had the returns pointed up and that kept most of the shallow end choppy but the deep end was more still and we got about a 1/4 to 1/2 inch thick sheet across half the deep end. It extended into the skimmer through the wier door but never froze solid across the skimmer. Water still flowed the whole time, but if we hadn’t warmed up a bit the next day my presumption would have been we may have had a solid sheet across the top.

My presumption would also be that if I hadn’t been running the pumps we would have frozen solid across the top much earlier.